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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
use api::{DirtyRect, ExternalImageType, ImageFormat, ImageBufferKind};
use api::{DebugFlags, ImageDescriptor};
use api::units::*;
#[cfg(test)]
use api::{DocumentId, IdNamespace};
use crate::device::{TextureFilter, TextureFormatPair};
use crate::freelist::{FreeList, FreeListHandle, WeakFreeListHandle};
use crate::gpu_cache::{GpuCache, GpuCacheHandle};
use crate::gpu_types::{ImageSource, UvRectKind};
use crate::internal_types::{
CacheTextureId, Swizzle, SwizzleSettings, FrameStamp, FrameId,
TextureUpdateList, TextureUpdateSource, TextureSource,
TextureCacheAllocInfo, TextureCacheUpdate, TextureCacheCategory,
};
use crate::lru_cache::LRUCache;
use crate::profiler::{self, TransactionProfile};
use crate::resource_cache::{CacheItem, CachedImageData};
use crate::texture_pack::{
AllocatorList, AllocId, AtlasAllocatorList, ShelfAllocator, ShelfAllocatorOptions,
};
use std::cell::Cell;
use std::mem;
use std::rc::Rc;
use euclid::size2;
use malloc_size_of::{MallocSizeOf, MallocSizeOfOps};
/// Information about which shader will use the entry.
///
/// For batching purposes, it's beneficial to group some items in their
/// own textures if we know that they are used by a specific shader.
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum TargetShader {
Default,
Text,
}
/// The size of each region in shared cache texture arrays.
pub const TEXTURE_REGION_DIMENSIONS: i32 = 512;
/// Items in the texture cache can either be standalone textures,
/// or a sub-rect inside the shared cache.
#[derive(Clone, Debug)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum EntryDetails {
Standalone {
/// Number of bytes this entry allocates
size_in_bytes: usize,
},
Cache {
/// Origin within the texture layer where this item exists.
origin: DeviceIntPoint,
/// ID of the allocation specific to its allocator.
alloc_id: AllocId,
/// The allocated size in bytes for this entry.
allocated_size_in_bytes: usize,
},
}
impl EntryDetails {
fn describe(&self) -> DeviceIntPoint {
match *self {
EntryDetails::Standalone { .. } => DeviceIntPoint::zero(),
EntryDetails::Cache { origin, .. } => origin,
}
}
}
#[derive(Debug, PartialEq)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum AutoCacheEntryMarker {}
#[derive(Debug, PartialEq)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum ManualCacheEntryMarker {}
// Stores information related to a single entry in the texture
// cache. This is stored for each item whether it's in the shared
// cache or a standalone texture.
#[derive(Debug)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct CacheEntry {
/// Size of the requested item, in device pixels. Does not include any
/// padding for alignment that the allocator may have added to this entry's
/// allocation.
pub size: DeviceIntSize,
/// Details specific to standalone or shared items.
pub details: EntryDetails,
/// Arbitrary user data associated with this item.
pub user_data: [f32; 4],
/// The last frame this item was requested for rendering.
// TODO(gw): This stamp is only used for picture cache tiles, and some checks
// in the glyph cache eviction code. We could probably remove it
// entirely in future (or move to PictureCacheEntry).
pub last_access: FrameStamp,
/// Handle to the resource rect in the GPU cache.
pub uv_rect_handle: GpuCacheHandle,
/// Image format of the data that the entry expects.
pub input_format: ImageFormat,
pub filter: TextureFilter,
pub swizzle: Swizzle,
/// The actual device texture ID this is part of.
pub texture_id: CacheTextureId,
/// Optional notice when the entry is evicted from the cache.
pub eviction_notice: Option<EvictionNotice>,
/// The type of UV rect this entry specifies.
pub uv_rect_kind: UvRectKind,
pub shader: TargetShader,
}
malloc_size_of::malloc_size_of_is_0!(
CacheEntry,
AutoCacheEntryMarker, ManualCacheEntryMarker
);
impl CacheEntry {
// Create a new entry for a standalone texture.
fn new_standalone(
texture_id: CacheTextureId,
last_access: FrameStamp,
params: &CacheAllocParams,
swizzle: Swizzle,
size_in_bytes: usize,
) -> Self {
CacheEntry {
size: params.descriptor.size,
user_data: params.user_data,
last_access,
details: EntryDetails::Standalone {
size_in_bytes,
},
texture_id,
input_format: params.descriptor.format,
filter: params.filter,
swizzle,
uv_rect_handle: GpuCacheHandle::new(),
eviction_notice: None,
uv_rect_kind: params.uv_rect_kind,
shader: TargetShader::Default,
}
}
// Update the GPU cache for this texture cache entry.
// This ensures that the UV rect, and texture layer index
// are up to date in the GPU cache for vertex shaders
// to fetch from.
fn update_gpu_cache(&mut self, gpu_cache: &mut GpuCache) {
if let Some(mut request) = gpu_cache.request(&mut self.uv_rect_handle) {
let origin = self.details.describe();
let image_source = ImageSource {
p0: origin.to_f32(),
p1: (origin + self.size).to_f32(),
user_data: self.user_data,
uv_rect_kind: self.uv_rect_kind,
};
image_source.write_gpu_blocks(&mut request);
}
}
fn evict(&self) {
if let Some(eviction_notice) = self.eviction_notice.as_ref() {
eviction_notice.notify();
}
}
fn alternative_input_format(&self) -> ImageFormat {
match self.input_format {
ImageFormat::RGBA8 => ImageFormat::BGRA8,
ImageFormat::BGRA8 => ImageFormat::RGBA8,
other => other,
}
}
}
/// A texture cache handle is a weak reference to a cache entry.
///
/// If the handle has not been inserted into the cache yet, or if the entry was
/// previously inserted and then evicted, lookup of the handle will fail, and
/// the cache handle needs to re-upload this item to the texture cache (see
/// request() below).
#[derive(MallocSizeOf,Clone,PartialEq,Debug)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum TextureCacheHandle {
/// A fresh handle.
Empty,
/// A handle for an entry with automatic eviction.
Auto(WeakFreeListHandle<AutoCacheEntryMarker>),
/// A handle for an entry with manual eviction.
Manual(WeakFreeListHandle<ManualCacheEntryMarker>)
}
impl TextureCacheHandle {
pub fn invalid() -> Self {
TextureCacheHandle::Empty
}
}
/// Describes the eviction policy for a given entry in the texture cache.
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum Eviction {
/// The entry will be evicted under the normal rules (which differ between
/// standalone and shared entries).
Auto,
/// The entry will not be evicted until the policy is explicitly set to a
/// different value.
Manual,
}
// An eviction notice is a shared condition useful for detecting
// when a TextureCacheHandle gets evicted from the TextureCache.
// It is optionally installed to the TextureCache when an update()
// is scheduled. A single notice may be shared among any number of
// TextureCacheHandle updates. The notice may then be subsequently
// checked to see if any of the updates using it have been evicted.
#[derive(Clone, Debug, Default)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct EvictionNotice {
evicted: Rc<Cell<bool>>,
}
impl EvictionNotice {
fn notify(&self) {
self.evicted.set(true);
}
pub fn check(&self) -> bool {
if self.evicted.get() {
self.evicted.set(false);
true
} else {
false
}
}
}
/// The different budget types for the texture cache. Each type has its own
/// memory budget. Once the budget is exceeded, entries with automatic eviction
/// are evicted. Entries with manual eviction share the same budget but are not
/// evicted once the budget is exceeded.
/// Keeping separate budgets ensures that we don't evict entries from unrelated
/// textures if one texture gets full.
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
#[repr(u8)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
enum BudgetType {
SharedColor8Linear,
SharedColor8Nearest,
SharedColor8Glyphs,
SharedAlpha8,
SharedAlpha8Glyphs,
SharedAlpha16,
Standalone,
}
impl BudgetType {
pub const COUNT: usize = 7;
pub const VALUES: [BudgetType; BudgetType::COUNT] = [
BudgetType::SharedColor8Linear,
BudgetType::SharedColor8Nearest,
BudgetType::SharedColor8Glyphs,
BudgetType::SharedAlpha8,
BudgetType::SharedAlpha8Glyphs,
BudgetType::SharedAlpha16,
BudgetType::Standalone,
];
pub const PRESSURE_COUNTERS: [usize; BudgetType::COUNT] = [
profiler::ATLAS_COLOR8_LINEAR_PRESSURE,
profiler::ATLAS_COLOR8_NEAREST_PRESSURE,
profiler::ATLAS_COLOR8_GLYPHS_PRESSURE,
profiler::ATLAS_ALPHA8_PRESSURE,
profiler::ATLAS_ALPHA8_GLYPHS_PRESSURE,
profiler::ATLAS_ALPHA16_PRESSURE,
profiler::ATLAS_STANDALONE_PRESSURE,
];
pub fn iter() -> impl Iterator<Item = BudgetType> {
BudgetType::VALUES.iter().cloned()
}
}
/// A set of lazily allocated, fixed size, texture arrays for each format the
/// texture cache supports.
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
struct SharedTextures {
color8_nearest: AllocatorList<ShelfAllocator, TextureParameters>,
alpha8_linear: AllocatorList<ShelfAllocator, TextureParameters>,
alpha8_glyphs: AllocatorList<ShelfAllocator, TextureParameters>,
alpha16_linear: AllocatorList<ShelfAllocator, TextureParameters>,
color8_linear: AllocatorList<ShelfAllocator, TextureParameters>,
color8_glyphs: AllocatorList<ShelfAllocator, TextureParameters>,
bytes_per_texture_of_type: [i32 ; BudgetType::COUNT],
next_compaction_idx: usize,
}
impl SharedTextures {
/// Mints a new set of shared textures.
fn new(color_formats: TextureFormatPair<ImageFormat>, config: &TextureCacheConfig) -> Self {
let mut bytes_per_texture_of_type = [0 ; BudgetType::COUNT];
// Used primarily for cached shadow masks. There can be lots of
// these on some pages like francine, but most pages don't use it
// much.
// Most content tends to fit into two 512x512 textures. We are
// conservatively using 1024x1024 to fit everything in a single
// texture and avoid breaking batches, but it's worth checking
// whether it would actually lead to a lot of batch breaks in
// practice.
let alpha8_linear = AllocatorList::new(
config.alpha8_texture_size,
ShelfAllocatorOptions {
num_columns: 1,
alignment: size2(8, 8),
.. ShelfAllocatorOptions::default()
},
TextureParameters {
formats: TextureFormatPair::from(ImageFormat::R8),
filter: TextureFilter::Linear,
},
);
bytes_per_texture_of_type[BudgetType::SharedAlpha8 as usize] =
config.alpha8_texture_size * config.alpha8_texture_size;
// The cache for alpha glyphs (separate to help with batching).
let alpha8_glyphs = AllocatorList::new(
config.alpha8_glyph_texture_size,
ShelfAllocatorOptions {
num_columns: if config.alpha8_glyph_texture_size >= 1024 { 2 } else { 1 },
alignment: size2(4, 8),
.. ShelfAllocatorOptions::default()
},
TextureParameters {
formats: TextureFormatPair::from(ImageFormat::R8),
filter: TextureFilter::Linear,
},
);
bytes_per_texture_of_type[BudgetType::SharedAlpha8Glyphs as usize] =
config.alpha8_glyph_texture_size * config.alpha8_glyph_texture_size;
// Used for experimental hdr yuv texture support, but not used in
// production Firefox.
let alpha16_linear = AllocatorList::new(
config.alpha16_texture_size,
ShelfAllocatorOptions {
num_columns: if config.alpha16_texture_size >= 1024 { 2 } else { 1 },
alignment: size2(8, 8),
.. ShelfAllocatorOptions::default()
},
TextureParameters {
formats: TextureFormatPair::from(ImageFormat::R16),
filter: TextureFilter::Linear,
},
);
bytes_per_texture_of_type[BudgetType::SharedAlpha16 as usize] =
ImageFormat::R16.bytes_per_pixel() *
config.alpha16_texture_size * config.alpha16_texture_size;
// The primary cache for images, etc.
let color8_linear = AllocatorList::new(
config.color8_linear_texture_size,
ShelfAllocatorOptions {
num_columns: if config.color8_linear_texture_size >= 1024 { 2 } else { 1 },
alignment: size2(16, 16),
.. ShelfAllocatorOptions::default()
},
TextureParameters {
formats: color_formats.clone(),
filter: TextureFilter::Linear,
},
);
bytes_per_texture_of_type[BudgetType::SharedColor8Linear as usize] =
color_formats.internal.bytes_per_pixel() *
config.color8_linear_texture_size * config.color8_linear_texture_size;
// The cache for subpixel-AA and bitmap glyphs (separate to help with batching).
let color8_glyphs = AllocatorList::new(
config.color8_glyph_texture_size,
ShelfAllocatorOptions {
num_columns: if config.color8_glyph_texture_size >= 1024 { 2 } else { 1 },
alignment: size2(4, 8),
.. ShelfAllocatorOptions::default()
},
TextureParameters {
formats: color_formats.clone(),
filter: TextureFilter::Linear,
},
);
bytes_per_texture_of_type[BudgetType::SharedColor8Glyphs as usize] =
color_formats.internal.bytes_per_pixel() *
config.color8_glyph_texture_size * config.color8_glyph_texture_size;
// Used for image-rendering: crisp. This is mostly favicons, which
// are small. Some other images use it too, but those tend to be
// larger than 512x512 and thus don't use the shared cache anyway.
let color8_nearest = AllocatorList::new(
config.color8_nearest_texture_size,
ShelfAllocatorOptions::default(),
TextureParameters {
formats: color_formats.clone(),
filter: TextureFilter::Nearest,
}
);
bytes_per_texture_of_type[BudgetType::SharedColor8Nearest as usize] =
color_formats.internal.bytes_per_pixel() *
config.color8_nearest_texture_size * config.color8_nearest_texture_size;
Self {
alpha8_linear,
alpha8_glyphs,
alpha16_linear,
color8_linear,
color8_glyphs,
color8_nearest,
bytes_per_texture_of_type,
next_compaction_idx: 0,
}
}
/// Clears each texture in the set, with the given set of pending updates.
fn clear(&mut self, updates: &mut TextureUpdateList) {
let texture_dealloc_cb = &mut |texture_id| {
updates.push_free(texture_id);
};
self.alpha8_linear.clear(texture_dealloc_cb);
self.alpha8_glyphs.clear(texture_dealloc_cb);
self.alpha16_linear.clear(texture_dealloc_cb);
self.color8_linear.clear(texture_dealloc_cb);
self.color8_nearest.clear(texture_dealloc_cb);
self.color8_glyphs.clear(texture_dealloc_cb);
}
/// Returns a mutable borrow for the shared texture array matching the parameters.
fn select(
&mut self, external_format: ImageFormat, filter: TextureFilter, shader: TargetShader,
) -> (&mut dyn AtlasAllocatorList<TextureParameters>, BudgetType) {
match external_format {
ImageFormat::R8 => {
assert_eq!(filter, TextureFilter::Linear);
match shader {
TargetShader::Text => {
(&mut self.alpha8_glyphs, BudgetType::SharedAlpha8Glyphs)
},
_ => (&mut self.alpha8_linear, BudgetType::SharedAlpha8),
}
}
ImageFormat::R16 => {
assert_eq!(filter, TextureFilter::Linear);
(&mut self.alpha16_linear, BudgetType::SharedAlpha16)
}
ImageFormat::RGBA8 |
ImageFormat::BGRA8 => {
match (filter, shader) {
(TextureFilter::Linear, TargetShader::Text) => {
(&mut self.color8_glyphs, BudgetType::SharedColor8Glyphs)
},
(TextureFilter::Linear, _) => {
(&mut self.color8_linear, BudgetType::SharedColor8Linear)
},
(TextureFilter::Nearest, _) => {
(&mut self.color8_nearest, BudgetType::SharedColor8Nearest)
},
_ => panic!("Unexpected filter {:?}", filter),
}
}
_ => panic!("Unexpected format {:?}", external_format),
}
}
/// How many bytes a single texture of the given type takes up, for the
/// configured texture sizes.
fn bytes_per_shared_texture(&self, budget_type: BudgetType) -> usize {
self.bytes_per_texture_of_type[budget_type as usize] as usize
}
fn has_multiple_textures(&self, budget_type: BudgetType) -> bool {
match budget_type {
BudgetType::SharedColor8Linear => self.color8_linear.allocated_textures() > 1,
BudgetType::SharedColor8Nearest => self.color8_nearest.allocated_textures() > 1,
BudgetType::SharedColor8Glyphs => self.color8_glyphs.allocated_textures() > 1,
BudgetType::SharedAlpha8 => self.alpha8_linear.allocated_textures() > 1,
BudgetType::SharedAlpha8Glyphs => self.alpha8_glyphs.allocated_textures() > 1,
BudgetType::SharedAlpha16 => self.alpha16_linear.allocated_textures() > 1,
BudgetType::Standalone => false,
}
}
}
/// Container struct for the various parameters used in cache allocation.
struct CacheAllocParams {
descriptor: ImageDescriptor,
filter: TextureFilter,
user_data: [f32; 4],
uv_rect_kind: UvRectKind,
shader: TargetShader,
}
/// Startup parameters for the texture cache.
///
/// Texture sizes must be at least 512.
#[derive(Clone)]
pub struct TextureCacheConfig {
pub color8_linear_texture_size: i32,
pub color8_nearest_texture_size: i32,
pub color8_glyph_texture_size: i32,
pub alpha8_texture_size: i32,
pub alpha8_glyph_texture_size: i32,
pub alpha16_texture_size: i32,
}
impl TextureCacheConfig {
pub const DEFAULT: Self = TextureCacheConfig {
color8_linear_texture_size: 2048,
color8_nearest_texture_size: 512,
color8_glyph_texture_size: 2048,
alpha8_texture_size: 1024,
alpha8_glyph_texture_size: 2048,
alpha16_texture_size: 512,
};
}
/// General-purpose manager for images in GPU memory. This includes images,
/// rasterized glyphs, rasterized blobs, cached render tasks, etc.
///
/// The texture cache is owned and managed by the RenderBackend thread, and
/// produces a series of commands to manipulate the textures on the Renderer
/// thread. These commands are executed before any rendering is performed for
/// a given frame.
///
/// Entries in the texture cache are not guaranteed to live past the end of the
/// frame in which they are requested, and may be evicted. The API supports
/// querying whether an entry is still available.
///
/// The TextureCache is different from the GpuCache in that the former stores
/// images, whereas the latter stores data and parameters for use in the shaders.
/// This means that the texture cache can be visualized, which is a good way to
/// understand how it works. Enabling gfx.webrender.debug.texture-cache shows a
/// live view of its contents in Firefox.
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct TextureCache {
/// Set of texture arrays in different formats used for the shared cache.
shared_textures: SharedTextures,
/// Maximum texture size supported by hardware.
max_texture_size: i32,
/// Maximum texture size before it is considered preferable to break the
/// texture into tiles.
tiling_threshold: i32,
/// Settings on using texture unit swizzling.
swizzle: Option<SwizzleSettings>,
/// The current set of debug flags.
debug_flags: DebugFlags,
/// The next unused virtual texture ID. Monotonically increasing.
pub next_id: CacheTextureId,
/// A list of allocations and updates that need to be applied to the texture
/// cache in the rendering thread this frame.
#[cfg_attr(all(feature = "serde", any(feature = "capture", feature = "replay")), serde(skip))]
pub pending_updates: TextureUpdateList,
/// The current `FrameStamp`. Used for cache eviction policies.
now: FrameStamp,
/// Cache of texture cache handles with automatic lifetime management, evicted
/// in a least-recently-used order.
lru_cache: LRUCache<CacheEntry, AutoCacheEntryMarker>,
/// Cache of texture cache entries with manual liftime management.
manual_entries: FreeList<CacheEntry, ManualCacheEntryMarker>,
/// Strong handles for the manual_entries FreeList.
manual_handles: Vec<FreeListHandle<ManualCacheEntryMarker>>,
/// Memory usage of allocated entries in all of the shared or standalone
/// textures. Includes both manually and automatically evicted entries.
bytes_allocated: [usize ; BudgetType::COUNT],
}
impl TextureCache {
/// The maximum number of items that will be evicted per frame. This limit helps avoid jank
/// on frames where we want to evict a large number of items. Instead, we'd prefer to drop
/// the items incrementally over a number of frames, even if that means the total allocated
/// size of the cache is above the desired threshold for a small number of frames.
const MAX_EVICTIONS_PER_FRAME: usize = 32;
pub fn new(
max_texture_size: i32,
tiling_threshold: i32,
color_formats: TextureFormatPair<ImageFormat>,
swizzle: Option<SwizzleSettings>,
config: &TextureCacheConfig,
) -> Self {
let pending_updates = TextureUpdateList::new();
// Shared texture cache controls swizzling on a per-entry basis, assuming that
// the texture as a whole doesn't need to be swizzled (but only some entries do).
// It would be possible to support this, but not needed at the moment.
assert!(color_formats.internal != ImageFormat::BGRA8 ||
swizzle.map_or(true, |s| s.bgra8_sampling_swizzle == Swizzle::default())
);
let next_texture_id = CacheTextureId(1);
TextureCache {
shared_textures: SharedTextures::new(color_formats, config),
max_texture_size,
tiling_threshold,
swizzle,
debug_flags: DebugFlags::empty(),
next_id: next_texture_id,
pending_updates,
now: FrameStamp::INVALID,
lru_cache: LRUCache::new(BudgetType::COUNT),
manual_entries: FreeList::new(),
manual_handles: Vec::new(),
bytes_allocated: [0 ; BudgetType::COUNT],
}
}
/// Creates a TextureCache and sets it up with a valid `FrameStamp`, which
/// is useful for avoiding panics when instantiating the `TextureCache`
/// directly from unit test code.
#[cfg(test)]
pub fn new_for_testing(
max_texture_size: i32,
image_format: ImageFormat,
) -> Self {
let mut cache = Self::new(
max_texture_size,
max_texture_size,
TextureFormatPair::from(image_format),
None,
&TextureCacheConfig::DEFAULT,
);
let mut now = FrameStamp::first(DocumentId::new(IdNamespace(1), 1));
now.advance();
cache.begin_frame(now, &mut TransactionProfile::new());
cache
}
pub fn set_debug_flags(&mut self, flags: DebugFlags) {
self.debug_flags = flags;
}
/// Clear all entries in the texture cache. This is a fairly drastic
/// step that should only be called very rarely.
pub fn clear_all(&mut self) {
// Evict all manual eviction handles
let manual_handles = mem::replace(
&mut self.manual_handles,
Vec::new(),
);
for handle in manual_handles {
let entry = self.manual_entries.free(handle);
self.evict_impl(entry);
}
// Evict all auto (LRU) cache handles
for budget_type in BudgetType::iter() {
while let Some(entry) = self.lru_cache.pop_oldest(budget_type as u8) {
entry.evict();
self.free(&entry);
}
}
// Free the picture and shared textures
self.shared_textures.clear(&mut self.pending_updates);
self.pending_updates.note_clear();
}
/// Called at the beginning of each frame.
pub fn begin_frame(&mut self, stamp: FrameStamp, profile: &mut TransactionProfile) {
debug_assert!(!self.now.is_valid());
profile_scope!("begin_frame");
self.now = stamp;
// Texture cache eviction is done at the start of the frame. This ensures that
// we won't evict items that have been requested on this frame.
// It also frees up space in the cache for items allocated later in the frame
// potentially reducing texture allocations and fragmentation.
self.evict_items_from_cache_if_required(profile);
}
pub fn end_frame(&mut self, profile: &mut TransactionProfile) {
debug_assert!(self.now.is_valid());
let updates = &mut self.pending_updates; // To avoid referring to self in the closure.
let callback = &mut|texture_id| { updates.push_free(texture_id); };
// Release of empty shared textures is done at the end of the frame. That way, if the
// eviction at the start of the frame frees up a texture, that is then subsequently
// used during the frame, we avoid doing a free/alloc for it.
self.shared_textures.alpha8_linear.release_empty_textures(callback);
self.shared_textures.alpha8_glyphs.release_empty_textures(callback);
self.shared_textures.alpha16_linear.release_empty_textures(callback);
self.shared_textures.color8_linear.release_empty_textures(callback);
self.shared_textures.color8_nearest.release_empty_textures(callback);
self.shared_textures.color8_glyphs.release_empty_textures(callback);
for budget in BudgetType::iter() {
let threshold = self.get_eviction_threshold(budget);
let pressure = self.bytes_allocated[budget as usize] as f32 / threshold as f32;
profile.set(BudgetType::PRESSURE_COUNTERS[budget as usize], pressure);
}
profile.set(profiler::ATLAS_A8_PIXELS, self.shared_textures.alpha8_linear.allocated_space());
profile.set(profiler::ATLAS_A8_TEXTURES, self.shared_textures.alpha8_linear.allocated_textures());
profile.set(profiler::ATLAS_A8_GLYPHS_PIXELS, self.shared_textures.alpha8_glyphs.allocated_space());
profile.set(profiler::ATLAS_A8_GLYPHS_TEXTURES, self.shared_textures.alpha8_glyphs.allocated_textures());
profile.set(profiler::ATLAS_A16_PIXELS, self.shared_textures.alpha16_linear.allocated_space());
profile.set(profiler::ATLAS_A16_TEXTURES, self.shared_textures.alpha16_linear.allocated_textures());
profile.set(profiler::ATLAS_RGBA8_LINEAR_PIXELS, self.shared_textures.color8_linear.allocated_space());
profile.set(profiler::ATLAS_RGBA8_LINEAR_TEXTURES, self.shared_textures.color8_linear.allocated_textures());
profile.set(profiler::ATLAS_RGBA8_NEAREST_PIXELS, self.shared_textures.color8_nearest.allocated_space());
profile.set(profiler::ATLAS_RGBA8_NEAREST_TEXTURES, self.shared_textures.color8_nearest.allocated_textures());
profile.set(profiler::ATLAS_RGBA8_GLYPHS_PIXELS, self.shared_textures.color8_glyphs.allocated_space());
profile.set(profiler::ATLAS_RGBA8_GLYPHS_TEXTURES, self.shared_textures.color8_glyphs.allocated_textures());
let shared_bytes = [
BudgetType::SharedColor8Linear,
BudgetType::SharedColor8Nearest,
BudgetType::SharedColor8Glyphs,
BudgetType::SharedAlpha8,
BudgetType::SharedAlpha8Glyphs,
BudgetType::SharedAlpha16,
].iter().map(|b| self.bytes_allocated[*b as usize]).sum();
profile.set(profiler::ATLAS_ITEMS_MEM, profiler::bytes_to_mb(shared_bytes));
self.now = FrameStamp::INVALID;
}
pub fn run_compaction(&mut self, gpu_cache: &mut GpuCache) {
// Use the same order as BudgetType::VALUES so that we can index self.bytes_allocated
// with the same index.
let allocator_lists = [
&mut self.shared_textures.color8_linear,
&mut self.shared_textures.color8_nearest,
&mut self.shared_textures.color8_glyphs,
&mut self.shared_textures.alpha8_linear,
&mut self.shared_textures.alpha8_glyphs,
&mut self.shared_textures.alpha16_linear,
];
// Pick a texture type on which to try to run the compaction logic this frame.
let idx = self.shared_textures.next_compaction_idx;
// Number of moved pixels after which we stop attempting to move more items for this frame.
// The constant is up for adjustment, the main goal is to avoid causing frame spikes on
// low end GPUs.
let area_threshold = 512*512;
let mut changes = Vec::new();
allocator_lists[idx].try_compaction(area_threshold, &mut changes);
if changes.is_empty() {
// Nothing to do, we'll try another texture type next frame.
self.shared_textures.next_compaction_idx = (self.shared_textures.next_compaction_idx + 1) % allocator_lists.len();
}
for change in changes {
let bpp = allocator_lists[idx].texture_parameters().formats.internal.bytes_per_pixel();
// While the area of the image does not change, the area it occupies in the texture
// atlas may (in other words the number of wasted pixels can change), so we have
// to keep track of that.
let old_bytes = (change.old_rect.area() * bpp) as usize;
let new_bytes = (change.new_rect.area() * bpp) as usize;
self.bytes_allocated[idx] -= old_bytes;
self.bytes_allocated[idx] += new_bytes;
let entry = match change.handle {
TextureCacheHandle::Auto(handle) => self.lru_cache.get_opt_mut(&handle).unwrap(),
TextureCacheHandle::Manual(handle) => self.manual_entries.get_opt_mut(&handle).unwrap(),
TextureCacheHandle::Empty => { panic!("invalid handle"); }
};
entry.texture_id = change.new_tex;
entry.details = EntryDetails::Cache {
origin: change.new_rect.min,
alloc_id: change.new_id,
allocated_size_in_bytes: new_bytes,
};
gpu_cache.invalidate(&entry.uv_rect_handle);
entry.uv_rect_handle = GpuCacheHandle::new();
let src_rect = DeviceIntRect::from_origin_and_size(change.old_rect.min, entry.size);
let dst_rect = DeviceIntRect::from_origin_and_size(change.new_rect.min, entry.size);
self.pending_updates.push_copy(change.old_tex, &src_rect, change.new_tex, &dst_rect);
if self.debug_flags.contains(
DebugFlags::TEXTURE_CACHE_DBG |
DebugFlags::TEXTURE_CACHE_DBG_CLEAR_EVICTED)
{
self.pending_updates.push_debug_clear(
change.old_tex,
src_rect.min,
src_rect.width(),
src_rect.height(),
);
}
}
}
// Request an item in the texture cache. All images that will
// be used on a frame *must* have request() called on their
// handle, to update the last used timestamp and ensure
// that resources are not flushed from the cache too early.
//
// Returns true if the image needs to be uploaded to the
// texture cache (either never uploaded, or has been
// evicted on a previous frame).
pub fn request(&mut self, handle: &TextureCacheHandle, gpu_cache: &mut GpuCache) -> bool {
let now = self.now;
let entry = match handle {
TextureCacheHandle::Empty => None,
TextureCacheHandle::Auto(handle) => {
// Call touch rather than get_opt_mut so that the LRU index
// knows that the entry has been used.
self.lru_cache.touch(handle)
},
TextureCacheHandle::Manual(handle) => {
self.manual_entries.get_opt_mut(handle)
},
};
entry.map_or(true, |entry| {
// If an image is requested that is already in the cache,
// refresh the GPU cache data associated with this item.
entry.last_access = now;
entry.update_gpu_cache(gpu_cache);
false
})
}
fn get_entry_opt(&self, handle: &TextureCacheHandle) -> Option<&CacheEntry> {
match handle {
TextureCacheHandle::Empty => None,
TextureCacheHandle::Auto(handle) => self.lru_cache.get_opt(handle),
TextureCacheHandle::Manual(handle) => self.manual_entries.get_opt(handle),
}
}
fn get_entry_opt_mut(&mut self, handle: &TextureCacheHandle) -> Option<&mut CacheEntry> {
match handle {
TextureCacheHandle::Empty => None,
TextureCacheHandle::Auto(handle) => self.lru_cache.get_opt_mut(handle),
TextureCacheHandle::Manual(handle) => self.manual_entries.get_opt_mut(handle),
}
}
// Returns true if the image needs to be uploaded to the
// texture cache (either never uploaded, or has been
// evicted on a previous frame).
pub fn needs_upload(&self, handle: &TextureCacheHandle) -> bool {
!self.is_allocated(handle)
}
pub fn max_texture_size(&self) -> i32 {
self.max_texture_size
}
pub fn tiling_threshold(&self) -> i32 {
self.tiling_threshold
}
#[cfg(feature = "replay")]
pub fn color_formats(&self) -> TextureFormatPair<ImageFormat> {
self.shared_textures.color8_linear.texture_parameters().formats.clone()
}
#[cfg(feature = "replay")]
pub fn swizzle_settings(&self) -> Option<SwizzleSettings> {
self.swizzle
}
pub fn pending_updates(&mut self) -> TextureUpdateList {
mem::replace(&mut self.pending_updates, TextureUpdateList::new())
}
// Update the data stored by a given texture cache handle.
pub fn update(
&mut self,
handle: &mut TextureCacheHandle,
descriptor: ImageDescriptor,
filter: TextureFilter,
data: Option<CachedImageData>,
user_data: [f32; 4],
mut dirty_rect: ImageDirtyRect,
gpu_cache: &mut GpuCache,
eviction_notice: Option<&EvictionNotice>,
uv_rect_kind: UvRectKind,
eviction: Eviction,
shader: TargetShader,
) {
debug_assert!(self.now.is_valid());
// Determine if we need to allocate texture cache memory
// for this item. We need to reallocate if any of the following
// is true:
// - Never been in the cache
// - Has been in the cache but was evicted.
// - Exists in the cache but dimensions / format have changed.
let realloc = match self.get_entry_opt(handle) {
Some(entry) => {
entry.size != descriptor.size || (entry.input_format != descriptor.format &&
entry.alternative_input_format() != descriptor.format)
}
None => {
// Not allocated, or was previously allocated but has been evicted.
true
}
};
if realloc {
let params = CacheAllocParams { descriptor, filter, user_data, uv_rect_kind, shader };
self.allocate(¶ms, handle, eviction);
// If we reallocated, we need to upload the whole item again.
dirty_rect = DirtyRect::All;
}
let entry = self.get_entry_opt_mut(handle)
.expect("BUG: There must be an entry at this handle now");
// Install the new eviction notice for this update, if applicable.
entry.eviction_notice = eviction_notice.cloned();
entry.uv_rect_kind = uv_rect_kind;
// Invalidate the contents of the resource rect in the GPU cache.
// This ensures that the update_gpu_cache below will add
// the new information to the GPU cache.
//TODO: only invalidate if the parameters change?
gpu_cache.invalidate(&entry.uv_rect_handle);
// Upload the resource rect and texture array layer.
entry.update_gpu_cache(gpu_cache);
// Create an update command, which the render thread processes
// to upload the new image data into the correct location
// in GPU memory.
if let Some(data) = data {
// If the swizzling is supported, we always upload in the internal
// texture format (thus avoiding the conversion by the driver).
// Otherwise, pass the external format to the driver.
let origin = entry.details.describe();
let texture_id = entry.texture_id;
let size = entry.size;
let use_upload_format = self.swizzle.is_none();
let op = TextureCacheUpdate::new_update(
data,
&descriptor,
origin,
size,
use_upload_format,
&dirty_rect,
);
self.pending_updates.push_update(texture_id, op);
}
}
// Check if a given texture handle has a valid allocation
// in the texture cache.
pub fn is_allocated(&self, handle: &TextureCacheHandle) -> bool {
self.get_entry_opt(handle).is_some()
}
// Return the allocated size of the texture handle's associated data,
// or otherwise indicate the handle is invalid.
pub fn get_allocated_size(&self, handle: &TextureCacheHandle) -> Option<usize> {
self.get_entry_opt(handle).map(|entry| {
(entry.input_format.bytes_per_pixel() * entry.size.area()) as usize
})
}
// Retrieve the details of an item in the cache. This is used
// during batch creation to provide the resource rect address
// to the shaders and texture ID to the batching logic.
// This function will assert in debug modes if the caller
// tries to get a handle that was not requested this frame.
pub fn get(&self, handle: &TextureCacheHandle) -> CacheItem {
let (texture_id, uv_rect, swizzle, uv_rect_handle, user_data) = self.get_cache_location(handle);
CacheItem {
uv_rect_handle,
texture_id: TextureSource::TextureCache(
texture_id,
swizzle,
),
uv_rect,
user_data,
}
}
/// A more detailed version of get(). This allows access to the actual
/// device rect of the cache allocation.
///
/// Returns a tuple identifying the texture, the layer, the region,
/// and its GPU handle.
pub fn get_cache_location(
&self,
handle: &TextureCacheHandle,
) -> (CacheTextureId, DeviceIntRect, Swizzle, GpuCacheHandle, [f32; 4]) {
let entry = self
.get_entry_opt(handle)
.expect("BUG: was dropped from cache or not updated!");
debug_assert_eq!(entry.last_access, self.now);
let origin = entry.details.describe();
(
entry.texture_id,
DeviceIntRect::from_origin_and_size(origin, entry.size),
entry.swizzle,
entry.uv_rect_handle,
entry.user_data,
)
}
/// Internal helper function to evict a strong texture cache handle
fn evict_impl(
&mut self,
entry: CacheEntry,
) {
entry.evict();
self.free(&entry);
}
/// Evict a texture cache handle that was previously set to be in manual
/// eviction mode.
pub fn evict_handle(&mut self, handle: &TextureCacheHandle) {
match handle {
TextureCacheHandle::Manual(handle) => {
// Find the strong handle that matches this weak handle. If this
// ever shows up in profiles, we can make it a hash (but the number
// of manual eviction handles is typically small).
// Alternatively, we could make a more forgiving FreeList variant
// which does not differentiate between strong and weak handles.
let index = self.manual_handles.iter().position(|strong_handle| {
strong_handle.matches(handle)
});
if let Some(index) = index {
let handle = self.manual_handles.swap_remove(index);
let entry = self.manual_entries.free(handle);
self.evict_impl(entry);
}
}
TextureCacheHandle::Auto(handle) => {
if let Some(entry) = self.lru_cache.remove(handle) {
self.evict_impl(entry);
}
}
_ => {}
}
}
pub fn dump_color8_linear_as_svg(&self, output: &mut dyn std::io::Write) -> std::io::Result<()> {
self.shared_textures.color8_linear.dump_as_svg(output)
}
pub fn dump_color8_glyphs_as_svg(&self, output: &mut dyn std::io::Write) -> std::io::Result<()> {
self.shared_textures.color8_glyphs.dump_as_svg(output)
}
pub fn dump_alpha8_glyphs_as_svg(&self, output: &mut dyn std::io::Write) -> std::io::Result<()> {
self.shared_textures.alpha8_glyphs.dump_as_svg(output)
}
pub fn dump_alpha8_linear_as_svg(&self, output: &mut dyn std::io::Write) -> std::io::Result<()> {
self.shared_textures.alpha8_linear.dump_as_svg(output)
}
/// Get the eviction threshold, in bytes, for the given budget type.
fn get_eviction_threshold(&self, budget_type: BudgetType) -> usize {
if budget_type == BudgetType::Standalone {
// For standalone textures, the only reason to evict textures is
// to save GPU memory. Batching / draw call concerns do not apply
// to standalone textures, because unused textures don't cause
// extra draw calls.
return 8 * 1024 * 1024;
}
// For shared textures, evicting an entry only frees up GPU memory if it
// causes one of the shared textures to become empty, so we want to avoid
// getting slightly above the capacity of a texture.
// The other concern for shared textures is batching: The entries that
// are needed in the current frame should be distributed across as few
// shared textures as possible, to minimize the number of draw calls.
// Ideally we only want one texture per type under simple workloads.
let bytes_per_texture = self.shared_textures.bytes_per_shared_texture(budget_type);
// Number of allocated bytes under which we don't bother with evicting anything
// from the cache. Above the threshold we consider evicting the coldest items
// depending on how cold they are.
//
// Above all else we want to make sure that even after a heavy workload, the
// shared cache settles back to a single texture atlas per type over some reasonable
// period of time.
// This is achieved by the compaction logic which will try to consolidate items that
// are spread over multiple textures into few ones, and by evicting old items
// so that the compaction logic has room to do its job.
//
// The other goal is to leave enough empty space in the texture atlases
// so that we are not too likely to have to allocate a new texture atlas on
// the next frame if we switch to a new tab or load a new page. That's why
// the following thresholds are rather low. Note that even when above the threshold,
// we only evict cold items and ramp up the eviction pressure depending on the amount
// of allocated memory (See should_continue_evicting).
let ideal_utilization = match budget_type {
BudgetType::SharedAlpha8Glyphs | BudgetType::SharedColor8Glyphs => {
// Glyphs are usually small and tightly packed so they waste very little
// space in the cache.
bytes_per_texture * 2 / 3
}
_ => {
// Other types of images come with a variety of sizes making them more
// prone to wasting pixels and causing fragmentation issues so we put
// more pressure on them.
bytes_per_texture / 3
}
};
ideal_utilization
}
/// Returns whether to continue eviction and how cold an item need to be to be evicted.
///
/// If the None is returned, stop evicting.
/// If the Some(n) is returned, continue evicting if the coldest item hasn't been used
/// for more than n frames.
fn should_continue_evicting(
&self,
budget_type: BudgetType,
eviction_count: usize,
) -> Option<u64> {
let threshold = self.get_eviction_threshold(budget_type);
let bytes_allocated = self.bytes_allocated[budget_type as usize];
let uses_multiple_atlases = self.shared_textures.has_multiple_textures(budget_type);
// If current memory usage is below selected threshold, we can stop evicting items
// except when using shared texture atlases and more than one texture is in use.
// This is not very common but can happen due to fragmentation and the only way
// to get rid of that fragmentation is to continue evicting.
if bytes_allocated < threshold && !uses_multiple_atlases {
return None;
}
// Number of frames since last use that is considered too recent for eviction,
// depending on the cache pressure.
let age_theshold = match bytes_allocated / threshold {
0 => 400,
1 => 200,
2 => 100,
3 => 50,
4 => 25,
5 => 10,
6 => 5,
_ => 1,
};
// If current memory usage is significantly more than the threshold, keep evicting this frame
if bytes_allocated > 4 * threshold {
return Some(age_theshold);
}
// Otherwise, only allow evicting up to a certain number of items per frame. This allows evictions
// to be spread over a number of frames, to avoid frame spikes.
if eviction_count < Self::MAX_EVICTIONS_PER_FRAME {
return Some(age_theshold)
}
None
}
/// Evict old items from the shared and standalone caches, if we're over a
/// threshold memory usage value
fn evict_items_from_cache_if_required(&mut self, profile: &mut TransactionProfile) {
let previous_frame_id = self.now.frame_id() - 1;
let mut eviction_count = 0;
let mut youngest_evicted = FrameId::first();
for budget in BudgetType::iter() {
while let Some(age_threshold) = self.should_continue_evicting(
budget,
eviction_count,
) {
if let Some(entry) = self.lru_cache.peek_oldest(budget as u8) {
// Only evict this item if it wasn't used in the previous frame. The reason being that if it
// was used the previous frame then it will likely be used in this frame too, and we don't
// want to be continually evicting and reuploading the item every frame.
if entry.last_access.frame_id() + age_threshold > previous_frame_id {
// Since the LRU cache is ordered by frame access, we can break out of the loop here because
// we know that all remaining items were also used in the previous frame (or more recently).
break;
}
if entry.last_access.frame_id() > youngest_evicted {
youngest_evicted = entry.last_access.frame_id();
}
let entry = self.lru_cache.pop_oldest(budget as u8).unwrap();
entry.evict();
self.free(&entry);
eviction_count += 1;
} else {
// The LRU cache is empty, all remaining items use manual
// eviction. In this case, there's nothing we can do until
// the calling code manually evicts items to reduce the
// allocated cache size.
break;
}
}
}
if eviction_count > 0 {
profile.set(profiler::TEXTURE_CACHE_EVICTION_COUNT, eviction_count);
profile.set(
profiler::TEXTURE_CACHE_YOUNGEST_EVICTION,
self.now.frame_id().as_u64() - youngest_evicted.as_u64()
);
}
}
// Free a cache entry from the standalone list or shared cache.
fn free(&mut self, entry: &CacheEntry) {
match entry.details {
EntryDetails::Standalone { size_in_bytes, .. } => {
self.bytes_allocated[BudgetType::Standalone as usize] -= size_in_bytes;
// This is a standalone texture allocation. Free it directly.
self.pending_updates.push_free(entry.texture_id);
}
EntryDetails::Cache { origin, alloc_id, allocated_size_in_bytes } => {
let (allocator_list, budget_type) = self.shared_textures.select(
entry.input_format,
entry.filter,
entry.shader,
);
allocator_list.deallocate(entry.texture_id, alloc_id);
self.bytes_allocated[budget_type as usize] -= allocated_size_in_bytes;
if self.debug_flags.contains(
DebugFlags::TEXTURE_CACHE_DBG |
DebugFlags::TEXTURE_CACHE_DBG_CLEAR_EVICTED)
{
self.pending_updates.push_debug_clear(
entry.texture_id,
origin,
entry.size.width,
entry.size.height,
);
}
}
}
}
/// Allocate a block from the shared cache.
fn allocate_from_shared_cache(
&mut self,
params: &CacheAllocParams,
) -> (CacheEntry, BudgetType) {
let (allocator_list, budget_type) = self.shared_textures.select(
params.descriptor.format,
params.filter,
params.shader,
);
// To avoid referring to self in the closure.
let next_id = &mut self.next_id;
let pending_updates = &mut self.pending_updates;
let (texture_id, alloc_id, allocated_rect) = allocator_list.allocate(
params.descriptor.size,
&mut |size, parameters| {
let texture_id = *next_id;
next_id.0 += 1;
pending_updates.push_alloc(
texture_id,
TextureCacheAllocInfo {
target: ImageBufferKind::Texture2D,
width: size.width,
height: size.height,
format: parameters.formats.internal,
filter: parameters.filter,
is_shared_cache: true,
has_depth: false,
category: TextureCacheCategory::Atlas,
},
);
texture_id
},
);
let formats = &allocator_list.texture_parameters().formats;
let swizzle = if formats.external == params.descriptor.format {
Swizzle::default()
} else {
match self.swizzle {
Some(_) => Swizzle::Bgra,
None => Swizzle::default(),
}
};
let bpp = formats.internal.bytes_per_pixel();
let allocated_size_in_bytes = (allocated_rect.area() * bpp) as usize;
self.bytes_allocated[budget_type as usize] += allocated_size_in_bytes;
(CacheEntry {
size: params.descriptor.size,
user_data: params.user_data,
last_access: self.now,
details: EntryDetails::Cache {
origin: allocated_rect.min,
alloc_id,
allocated_size_in_bytes,
},
uv_rect_handle: GpuCacheHandle::new(),
input_format: params.descriptor.format,
filter: params.filter,
swizzle,
texture_id,
eviction_notice: None,
uv_rect_kind: params.uv_rect_kind,
shader: params.shader
}, budget_type)
}
// Returns true if the given image descriptor *may* be
// placed in the shared texture cache.
pub fn is_allowed_in_shared_cache(
&self,
filter: TextureFilter,
descriptor: &ImageDescriptor,
) -> bool {
let mut allowed_in_shared_cache = true;
if matches!(descriptor.format, ImageFormat::RGBA8 | ImageFormat::BGRA8)
&& filter == TextureFilter::Linear
{
// Allow the maximum that can fit in the linear color texture's two column layout.
let max = self.shared_textures.color8_linear.size() / 2;
allowed_in_shared_cache = descriptor.size.width.max(descriptor.size.height) <= max;
} else if descriptor.size.width > TEXTURE_REGION_DIMENSIONS {
allowed_in_shared_cache = false;
}
if descriptor.size.height > TEXTURE_REGION_DIMENSIONS {
allowed_in_shared_cache = false;
}
// TODO(gw): For now, alpha formats of the texture cache can only be linearly sampled.
// Nearest sampling gets a standalone texture.
// This is probably rare enough that it can be fixed up later.
if filter == TextureFilter::Nearest &&
descriptor.format.bytes_per_pixel() <= 2
{
allowed_in_shared_cache = false;
}
allowed_in_shared_cache
}
/// Allocate a render target via the pending updates sent to the renderer
pub fn alloc_render_target(
&mut self,
size: DeviceIntSize,
format: ImageFormat,
) -> CacheTextureId {
let texture_id = self.next_id;
self.next_id.0 += 1;
// Push a command to allocate device storage of the right size / format.
let info = TextureCacheAllocInfo {
target: ImageBufferKind::Texture2D,
width: size.width,
height: size.height,
format,
filter: TextureFilter::Linear,
is_shared_cache: false,
has_depth: false,
category: TextureCacheCategory::RenderTarget,
};
self.pending_updates.push_alloc(texture_id, info);
texture_id
}
/// Free an existing render target
pub fn free_render_target(
&mut self,
id: CacheTextureId,
) {
self.pending_updates.push_free(id);
}
/// Allocates a new standalone cache entry.
fn allocate_standalone_entry(
&mut self,
params: &CacheAllocParams,
) -> (CacheEntry, BudgetType) {
let texture_id = self.next_id;
self.next_id.0 += 1;
// Push a command to allocate device storage of the right size / format.
let info = TextureCacheAllocInfo {
target: ImageBufferKind::Texture2D,
width: params.descriptor.size.width,
height: params.descriptor.size.height,
format: params.descriptor.format,
filter: params.filter,
is_shared_cache: false,
has_depth: false,
category: TextureCacheCategory::Standalone,
};
let size_in_bytes = (info.width * info.height * info.format.bytes_per_pixel()) as usize;
self.bytes_allocated[BudgetType::Standalone as usize] += size_in_bytes;
self.pending_updates.push_alloc(texture_id, info);
// Special handing for BGRA8 textures that may need to be swizzled.
let swizzle = if params.descriptor.format == ImageFormat::BGRA8 {
self.swizzle.map(|s| s.bgra8_sampling_swizzle)
} else {
None
};
(CacheEntry::new_standalone(
texture_id,
self.now,
params,
swizzle.unwrap_or_default(),
size_in_bytes,
), BudgetType::Standalone)
}
/// Allocates a cache entry for the given parameters, and updates the
/// provided handle to point to the new entry.
fn allocate(
&mut self,
params: &CacheAllocParams,
handle: &mut TextureCacheHandle,
eviction: Eviction,
) {
debug_assert!(self.now.is_valid());
assert!(!params.descriptor.size.is_empty());
// If this image doesn't qualify to go in the shared (batching) cache,
// allocate a standalone entry.
let use_shared_cache = self.is_allowed_in_shared_cache(params.filter, ¶ms.descriptor);
let (new_cache_entry, budget_type) = if use_shared_cache {
self.allocate_from_shared_cache(params)
} else {
self.allocate_standalone_entry(params)
};
let details = new_cache_entry.details.clone();
let texture_id = new_cache_entry.texture_id;
// If the handle points to a valid cache entry, we want to replace the
// cache entry with our newly updated location. We also need to ensure
// that the storage (region or standalone) associated with the previous
// entry here gets freed.
//
// If the handle is invalid, we need to insert the data, and append the
// result to the corresponding vector.
let old_entry = match (&mut *handle, eviction) {
(TextureCacheHandle::Auto(handle), Eviction::Auto) => {
self.lru_cache.replace_or_insert(handle, budget_type as u8, new_cache_entry)
},
(TextureCacheHandle::Manual(handle), Eviction::Manual) => {
let entry = self.manual_entries.get_opt_mut(handle)
.expect("Don't call this after evicting");
Some(mem::replace(entry, new_cache_entry))
},
(TextureCacheHandle::Manual(_), Eviction::Auto) |
(TextureCacheHandle::Auto(_), Eviction::Manual) => {
panic!("Can't change eviction policy after initial allocation");
},
(TextureCacheHandle::Empty, Eviction::Auto) => {
let new_handle = self.lru_cache.push_new(budget_type as u8, new_cache_entry);
*handle = TextureCacheHandle::Auto(new_handle);
None
},
(TextureCacheHandle::Empty, Eviction::Manual) => {
let manual_handle = self.manual_entries.insert(new_cache_entry);
let new_handle = manual_handle.weak();
self.manual_handles.push(manual_handle);
*handle = TextureCacheHandle::Manual(new_handle);
None
},
};
if let Some(old_entry) = old_entry {
old_entry.evict();
self.free(&old_entry);
}
if let EntryDetails::Cache { alloc_id, .. } = details {
let allocator_list = self.shared_textures.select(
params.descriptor.format,
params.filter,
params.shader,
).0;
allocator_list.set_handle(texture_id, alloc_id, handle);
}
}
pub fn shared_alpha_expected_format(&self) -> ImageFormat {
self.shared_textures.alpha8_linear.texture_parameters().formats.external
}
pub fn shared_color_expected_format(&self) -> ImageFormat {
self.shared_textures.color8_linear.texture_parameters().formats.external
}
#[cfg(test)]
pub fn total_allocated_bytes_for_testing(&self) -> usize {
BudgetType::iter().map(|b| self.bytes_allocated[b as usize]).sum()
}
pub fn report_memory(&self, ops: &mut MallocSizeOfOps) -> usize {
self.lru_cache.size_of(ops)
}
}
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct TextureParameters {
pub formats: TextureFormatPair<ImageFormat>,
pub filter: TextureFilter,
}
impl TextureCacheUpdate {
// Constructs a TextureCacheUpdate operation to be passed to the
// rendering thread in order to do an upload to the right
// location in the texture cache.
fn new_update(
data: CachedImageData,
descriptor: &ImageDescriptor,
origin: DeviceIntPoint,
size: DeviceIntSize,
use_upload_format: bool,
dirty_rect: &ImageDirtyRect,
) -> TextureCacheUpdate {
let source = match data {
CachedImageData::Snapshot => {
panic!("Snapshots should not do texture uploads");
}
CachedImageData::Blob => {
panic!("The vector image should have been rasterized.");
}
CachedImageData::External(ext_image) => match ext_image.image_type {
ExternalImageType::TextureHandle(_) => {
panic!("External texture handle should not go through texture_cache.");
}
ExternalImageType::Buffer => TextureUpdateSource::External {
id: ext_image.id,
channel_index: ext_image.channel_index,
},
},
CachedImageData::Raw(bytes) => {
let finish = descriptor.offset +
descriptor.size.width * descriptor.format.bytes_per_pixel() +
(descriptor.size.height - 1) * descriptor.compute_stride();
assert!(bytes.len() >= finish as usize);
TextureUpdateSource::Bytes { data: bytes }
}
};
let format_override = if use_upload_format {
Some(descriptor.format)
} else {
None
};
match *dirty_rect {
DirtyRect::Partial(dirty) => {
// the dirty rectangle doesn't have to be within the area but has to intersect it, at least
let stride = descriptor.compute_stride();
let offset = descriptor.offset + dirty.min.y * stride + dirty.min.x * descriptor.format.bytes_per_pixel();
TextureCacheUpdate {
rect: DeviceIntRect::from_origin_and_size(
DeviceIntPoint::new(origin.x + dirty.min.x, origin.y + dirty.min.y),
DeviceIntSize::new(
dirty.width().min(size.width - dirty.min.x),
dirty.height().min(size.height - dirty.min.y),
),
),
source,
stride: Some(stride),
offset,
format_override,
}
}
DirtyRect::All => {
TextureCacheUpdate {
rect: DeviceIntRect::from_origin_and_size(origin, size),
source,
stride: descriptor.stride,
offset: descriptor.offset,
format_override,
}
}
}
}
}
#[cfg(test)]
mod test_texture_cache {
#[test]
fn check_allocation_size_balance() {
// Allocate some glyphs, observe the total allocation size, and free
// the glyphs again. Check that the total allocation size is back at the
// original value.
use crate::texture_cache::{TextureCache, TextureCacheHandle, Eviction, TargetShader};
use crate::gpu_cache::GpuCache;
use crate::device::TextureFilter;
use crate::gpu_types::UvRectKind;
use api::{ImageDescriptor, ImageDescriptorFlags, ImageFormat, DirtyRect};
use api::units::*;
use euclid::size2;
let mut texture_cache = TextureCache::new_for_testing(2048, ImageFormat::BGRA8);
let mut gpu_cache = GpuCache::new_for_testing();
let sizes: &[DeviceIntSize] = &[
size2(23, 27),
size2(15, 22),
size2(11, 5),
size2(20, 25),
size2(38, 41),
size2(11, 19),
size2(13, 21),
size2(37, 40),
size2(13, 15),
size2(14, 16),
size2(10, 9),
size2(25, 28),
];
let bytes_at_start = texture_cache.total_allocated_bytes_for_testing();
let handles: Vec<TextureCacheHandle> = sizes.iter().map(|size| {
let mut texture_cache_handle = TextureCacheHandle::invalid();
texture_cache.request(&texture_cache_handle, &mut gpu_cache);
texture_cache.update(
&mut texture_cache_handle,
ImageDescriptor {
size: *size,
stride: None,
format: ImageFormat::BGRA8,
flags: ImageDescriptorFlags::empty(),
offset: 0,
},
TextureFilter::Linear,
None,
[0.0; 4],
DirtyRect::All,
&mut gpu_cache,
None,
UvRectKind::Rect,
Eviction::Manual,
TargetShader::Text,
);
texture_cache_handle
}).collect();
let bytes_after_allocating = texture_cache.total_allocated_bytes_for_testing();
assert!(bytes_after_allocating > bytes_at_start);
for handle in handles {
texture_cache.evict_handle(&handle);
}
let bytes_at_end = texture_cache.total_allocated_bytes_for_testing();
assert_eq!(bytes_at_end, bytes_at_start);
}
}