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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
#define VECS_PER_SPECIFIC_BRUSH 3
#define WR_FEATURE_TEXTURE_2D
#include shared,prim_shared,brush
// UV and bounds for the source image
varying highp vec2 v_src_uv;
flat varying highp vec4 v_src_uv_sample_bounds;
// UV and bounds for the backdrop image
varying highp vec2 v_backdrop_uv;
flat varying highp vec4 v_backdrop_uv_sample_bounds;
// Flag to allow perspective interpolation of UV.
flat varying mediump vec2 v_perspective;
flat varying mediump ivec2 v_op;
#ifdef WR_VERTEX_SHADER
void get_uv(
int res_address,
vec2 f,
ivec2 texture_size,
float perspective_f,
out vec2 out_uv,
out vec4 out_uv_sample_bounds
) {
ImageSource res = fetch_image_source(res_address);
vec2 uv0 = res.uv_rect.p0;
vec2 uv1 = res.uv_rect.p1;
vec2 inv_texture_size = vec2(1.0) / vec2(texture_size);
f = get_image_quad_uv(res_address, f);
vec2 uv = mix(uv0, uv1, f);
out_uv = uv * inv_texture_size * perspective_f;
out_uv_sample_bounds = vec4(uv0 + vec2(0.5), uv1 - vec2(0.5)) * inv_texture_size.xyxy;
}
void brush_vs(
VertexInfo vi,
int prim_address,
RectWithEndpoint local_rect,
RectWithEndpoint segment_rect,
ivec4 prim_user_data,
int specific_resource_address,
mat4 transform,
PictureTask pic_task,
int brush_flags,
vec4 unused
) {
vec2 f = (vi.local_pos - local_rect.p0) / rect_size(local_rect);
float perspective_interpolate = (brush_flags & BRUSH_FLAG_PERSPECTIVE_INTERPOLATION) != 0 ? 1.0 : 0.0;
float perspective_f = mix(vi.world_pos.w, 1.0, perspective_interpolate);
v_perspective.x = perspective_interpolate;
v_op.x = prim_user_data.x;
get_uv(
prim_user_data.y,
f,
TEX_SIZE(sColor0).xy,
1.0,
v_backdrop_uv,
v_backdrop_uv_sample_bounds
);
get_uv(
prim_user_data.z,
f,
TEX_SIZE(sColor1).xy,
perspective_f,
v_src_uv,
v_src_uv_sample_bounds
);
}
#endif
#ifdef WR_FRAGMENT_SHADER
vec3 Multiply(vec3 Cb, vec3 Cs) {
return Cb * Cs;
}
vec3 Screen(vec3 Cb, vec3 Cs) {
return Cb + Cs - (Cb * Cs);
}
vec3 HardLight(vec3 Cb, vec3 Cs) {
vec3 m = Multiply(Cb, 2.0 * Cs);
vec3 s = Screen(Cb, 2.0 * Cs - 1.0);
vec3 edge = vec3(0.5, 0.5, 0.5);
return mix(m, s, step(edge, Cs));
}
// TODO: Worth doing with mix/step? Check GLSL output.
float ColorDodge(float Cb, float Cs) {
if (Cb == 0.0)
return 0.0;
else if (Cs == 1.0)
return 1.0;
else
return min(1.0, Cb / (1.0 - Cs));
}
// TODO: Worth doing with mix/step? Check GLSL output.
float ColorBurn(float Cb, float Cs) {
if (Cb == 1.0)
return 1.0;
else if (Cs == 0.0)
return 0.0;
else
return 1.0 - min(1.0, (1.0 - Cb) / Cs);
}
float SoftLight(float Cb, float Cs) {
if (Cs <= 0.5) {
return Cb - (1.0 - 2.0 * Cs) * Cb * (1.0 - Cb);
} else {
float D;
if (Cb <= 0.25)
D = ((16.0 * Cb - 12.0) * Cb + 4.0) * Cb;
else
D = sqrt(Cb);
return Cb + (2.0 * Cs - 1.0) * (D - Cb);
}
}
vec3 Difference(vec3 Cb, vec3 Cs) {
return abs(Cb - Cs);
}
// These functions below are taken from the spec.
// There's probably a much quicker way to implement
// them in GLSL...
float Sat(vec3 c) {
return max(c.r, max(c.g, c.b)) - min(c.r, min(c.g, c.b));
}
float Lum(vec3 c) {
vec3 f = vec3(0.3, 0.59, 0.11);
return dot(c, f);
}
vec3 ClipColor(vec3 C) {
float L = Lum(C);
float n = min(C.r, min(C.g, C.b));
float x = max(C.r, max(C.g, C.b));
if (n < 0.0)
C = L + (((C - L) * L) / (L - n));
if (x > 1.0)
C = L + (((C - L) * (1.0 - L)) / (x - L));
return C;
}
vec3 SetLum(vec3 C, float l) {
float d = l - Lum(C);
return ClipColor(C + d);
}
void SetSatInner(inout float Cmin, inout float Cmid, inout float Cmax, float s) {
if (Cmax > Cmin) {
Cmid = (((Cmid - Cmin) * s) / (Cmax - Cmin));
Cmax = s;
} else {
Cmid = 0.0;
Cmax = 0.0;
}
Cmin = 0.0;
}
vec3 SetSat(vec3 C, float s) {
if (C.r <= C.g) {
if (C.g <= C.b) {
SetSatInner(C.r, C.g, C.b, s);
} else {
if (C.r <= C.b) {
SetSatInner(C.r, C.b, C.g, s);
} else {
SetSatInner(C.b, C.r, C.g, s);
}
}
} else {
if (C.r <= C.b) {
SetSatInner(C.g, C.r, C.b, s);
} else {
if (C.g <= C.b) {
SetSatInner(C.g, C.b, C.r, s);
} else {
SetSatInner(C.b, C.g, C.r, s);
}
}
}
return C;
}
vec3 Hue(vec3 Cb, vec3 Cs) {
return SetLum(SetSat(Cs, Sat(Cb)), Lum(Cb));
}
vec3 Saturation(vec3 Cb, vec3 Cs) {
return SetLum(SetSat(Cb, Sat(Cs)), Lum(Cb));
}
vec3 Color(vec3 Cb, vec3 Cs) {
return SetLum(Cs, Lum(Cb));
}
vec3 Luminosity(vec3 Cb, vec3 Cs) {
return SetLum(Cb, Lum(Cs));
}
const int MixBlendMode_Multiply = 1;
const int MixBlendMode_Screen = 2;
const int MixBlendMode_Overlay = 3;
const int MixBlendMode_Darken = 4;
const int MixBlendMode_Lighten = 5;
const int MixBlendMode_ColorDodge = 6;
const int MixBlendMode_ColorBurn = 7;
const int MixBlendMode_HardLight = 8;
const int MixBlendMode_SoftLight = 9;
const int MixBlendMode_Difference = 10;
const int MixBlendMode_Exclusion = 11;
const int MixBlendMode_Hue = 12;
const int MixBlendMode_Saturation = 13;
const int MixBlendMode_Color = 14;
const int MixBlendMode_Luminosity = 15;
const int MixBlendMode_PlusLighter = 16;
Fragment brush_fs() {
float perspective_divisor = mix(gl_FragCoord.w, 1.0, v_perspective.x);
vec2 src_uv = v_src_uv * perspective_divisor;
src_uv = clamp(src_uv, v_src_uv_sample_bounds.xy, v_src_uv_sample_bounds.zw);
vec2 backdrop_uv = clamp(v_backdrop_uv, v_backdrop_uv_sample_bounds.xy, v_backdrop_uv_sample_bounds.zw);
vec4 Cb = texture(sColor0, backdrop_uv);
vec4 Cs = texture(sColor1, src_uv);
// The mix-blend-mode functions assume no premultiplied alpha
if (Cb.a != 0.0) {
Cb.rgb /= Cb.a;
}
if (Cs.a != 0.0) {
Cs.rgb /= Cs.a;
}
// Return yellow if none of the branches match (shouldn't happen).
vec4 result = vec4(1.0, 1.0, 0.0, 1.0);
// On Android v_op has been packed in to a vector to avoid a driver bug
// on Adreno 3xx. However, this runs in to another Adreno 3xx driver bug
// where the switch doesn't match any cases. Unpacking the value from the
// vec in to a local variable prior to the switch works around this, but
// gets optimized away by glslopt. Adding a bitwise AND prevents that.
// default: default: to appease angle_shader_validation
switch (v_op.x & 0xFF) {
case MixBlendMode_Multiply:
result.rgb = Multiply(Cb.rgb, Cs.rgb);
break;
case MixBlendMode_Overlay:
// Overlay is inverse of Hardlight
result.rgb = HardLight(Cs.rgb, Cb.rgb);
break;
case MixBlendMode_Darken:
result.rgb = min(Cs.rgb, Cb.rgb);
break;
case MixBlendMode_Lighten:
result.rgb = max(Cs.rgb, Cb.rgb);
break;
case MixBlendMode_ColorDodge:
result.r = ColorDodge(Cb.r, Cs.r);
result.g = ColorDodge(Cb.g, Cs.g);
result.b = ColorDodge(Cb.b, Cs.b);
break;
case MixBlendMode_ColorBurn:
result.r = ColorBurn(Cb.r, Cs.r);
result.g = ColorBurn(Cb.g, Cs.g);
result.b = ColorBurn(Cb.b, Cs.b);
break;
case MixBlendMode_HardLight:
result.rgb = HardLight(Cb.rgb, Cs.rgb);
break;
case MixBlendMode_SoftLight:
result.r = SoftLight(Cb.r, Cs.r);
result.g = SoftLight(Cb.g, Cs.g);
result.b = SoftLight(Cb.b, Cs.b);
break;
case MixBlendMode_Difference:
result.rgb = Difference(Cb.rgb, Cs.rgb);
break;
case MixBlendMode_Hue:
result.rgb = Hue(Cb.rgb, Cs.rgb);
break;
case MixBlendMode_Saturation:
result.rgb = Saturation(Cb.rgb, Cs.rgb);
break;
case MixBlendMode_Color:
result.rgb = Color(Cb.rgb, Cs.rgb);
break;
case MixBlendMode_Luminosity:
result.rgb = Luminosity(Cb.rgb, Cs.rgb);
break;
case MixBlendMode_Screen:
case MixBlendMode_Exclusion:
case MixBlendMode_PlusLighter:
// This should be unreachable, since we implement
// MixBlendMode::Screen, MixBlendMode::Exclusion and
// MixBlendMode::PlusLighter using glBlendFuncSeparate.
break;
default: break;
}
result.rgb = (1.0 - Cb.a) * Cs.rgb + Cb.a * result.rgb;
result.a = Cs.a;
result.rgb *= result.a;
return Fragment(result);
}
#endif