Implement color dodge and color burn blend modes

canvas/src/lib.rs

@@ -534,6 +534,8 @@ pub enum CompositeOperation {
     Overlay,
     Darken,
     Lighten,
+    ColorDodge,
+    ColorBurn,
     HardLight,
     Hue,
     Saturation,
@@ -555,6 +557,8 @@ impl CompositeOperation {
             CompositeOperation::Overlay => BlendMode::Overlay,
             CompositeOperation::Darken => BlendMode::Darken,
             CompositeOperation::Lighten => BlendMode::Lighten,
+            CompositeOperation::ColorDodge => BlendMode::ColorDodge,
+            CompositeOperation::ColorBurn => BlendMode::ColorBurn,
             CompositeOperation::HardLight => BlendMode::HardLight,
             CompositeOperation::Hue => BlendMode::Hue,
             CompositeOperation::Saturation => BlendMode::Saturation,

content/src/effects.rs

@@ -81,6 +81,10 @@ pub enum BlendMode {
     HardLight,
     Overlay,
 
+    // Dodge/burn
+    ColorDodge,
+    ColorBurn,
+
     // HSL
     Hue,
     Saturation,
@@ -118,11 +122,13 @@ impl BlendMode {
             BlendMode::Xor |
             BlendMode::Lighter |
             BlendMode::Lighten |
+            BlendMode::Darken |
             BlendMode::Multiply |
             BlendMode::Screen |
             BlendMode::HardLight |
             BlendMode::Overlay |
-            BlendMode::Darken |
+            BlendMode::ColorDodge |
+            BlendMode::ColorBurn |
             BlendMode::Hue |
             BlendMode::Saturation |
             BlendMode::Color |

renderer/src/gpu/renderer.rs

@@ -10,13 +10,13 @@
 
 use crate::gpu::debug::DebugUIPresenter;
 use crate::gpu::options::{DestFramebuffer, RendererOptions};
-use crate::gpu::shaders::{AlphaTileHSLProgram, AlphaTileOverlayProgram, AlphaTileProgram};
+use crate::gpu::shaders::{AlphaTileDodgeBurnProgram, AlphaTileHSLProgram, AlphaTileOverlayProgram};
-use crate::gpu::shaders::{AlphaTileVertexArray, CopyTileProgram, CopyTileVertexArray, FillProgram};
+use crate::gpu::shaders::{AlphaTileProgram, AlphaTileVertexArray, CopyTileProgram};
-use crate::gpu::shaders::{FillVertexArray, FilterBasicProgram, FilterBasicVertexArray};
+use crate::gpu::shaders::{CopyTileVertexArray, FillProgram, FillVertexArray, FilterBasicProgram};
-use crate::gpu::shaders::{FilterTextProgram, FilterTextVertexArray, MAX_FILLS_PER_BATCH};
+use crate::gpu::shaders::{FilterBasicVertexArray, FilterTextProgram, FilterTextVertexArray};
-use crate::gpu::shaders::{MaskTileProgram, MaskTileVertexArray, ReprojectionProgram};
+use crate::gpu::shaders::{MAX_FILLS_PER_BATCH, MaskTileProgram, MaskTileVertexArray};
-use crate::gpu::shaders::{ReprojectionVertexArray, SolidTileProgram, SolidTileVertexArray};
+use crate::gpu::shaders::{ReprojectionProgram, ReprojectionVertexArray, SolidTileProgram};
-use crate::gpu::shaders::{StencilProgram, StencilVertexArray};
+use crate::gpu::shaders::{SolidTileVertexArray, StencilProgram, StencilVertexArray};
 use crate::gpu_data::{AlphaTile, FillBatchPrimitive, MaskTile, PaintData, PaintPageContents};
 use crate::gpu_data::{PaintPageId, RenderCommand, SolidTileVertex};
 use crate::options::BoundingQuad;
@@ -78,6 +78,7 @@ where
     solid_tile_program: SolidTileProgram<D>,
     alpha_tile_program: AlphaTileProgram<D>,
     alpha_tile_overlay_program: AlphaTileOverlayProgram<D>,
+    alpha_tile_dodgeburn_program: AlphaTileDodgeBurnProgram<D>,
     alpha_tile_hsl_program: AlphaTileHSLProgram<D>,
     mask_winding_tile_vertex_array: MaskTileVertexArray<D>,
     mask_evenodd_tile_vertex_array: MaskTileVertexArray<D>,
@@ -85,6 +86,7 @@ where
     solid_tile_vertex_array: SolidTileVertexArray<D>,
     alpha_tile_vertex_array: AlphaTileVertexArray<D>,
     alpha_tile_overlay_vertex_array: AlphaTileVertexArray<D>,
+    alpha_tile_dodgeburn_vertex_array: AlphaTileVertexArray<D>,
     alpha_tile_hsl_vertex_array: AlphaTileVertexArray<D>,
     area_lut_texture: D::Texture,
     alpha_tile_vertex_buffer: D::Buffer,
@@ -157,6 +159,7 @@ where
         let solid_tile_program = SolidTileProgram::new(&device, resources);
         let alpha_tile_program = AlphaTileProgram::new(&device, resources);
         let alpha_tile_overlay_program = AlphaTileOverlayProgram::new(&device, resources);
+        let alpha_tile_dodgeburn_program = AlphaTileDodgeBurnProgram::new(&device, resources);
         let alpha_tile_hsl_program = AlphaTileHSLProgram::new(&device, resources);
         let filter_basic_program = FilterBasicProgram::new(&device, resources);
         let filter_text_program = FilterTextProgram::new(&device, resources);
@@ -217,6 +220,12 @@ where
             &alpha_tile_vertex_buffer,
             &quads_vertex_indices_buffer,
         );
+        let alpha_tile_dodgeburn_vertex_array = AlphaTileVertexArray::new(
+            &device,
+            &alpha_tile_dodgeburn_program.alpha_tile_program,
+            &alpha_tile_vertex_buffer,
+            &quads_vertex_indices_buffer,
+        );
         let alpha_tile_hsl_vertex_array = AlphaTileVertexArray::new(
             &device,
             &alpha_tile_hsl_program.alpha_tile_program,
@@ -285,6 +294,7 @@ where
             solid_tile_program,
             alpha_tile_program,
             alpha_tile_overlay_program,
+            alpha_tile_dodgeburn_program,
             alpha_tile_hsl_program,
             mask_winding_tile_vertex_array,
             mask_evenodd_tile_vertex_array,
@@ -292,6 +302,7 @@ where
             solid_tile_vertex_array,
             alpha_tile_vertex_array,
             alpha_tile_overlay_vertex_array,
+            alpha_tile_dodgeburn_vertex_array,
             alpha_tile_hsl_vertex_array,
             area_lut_texture,
             alpha_tile_vertex_buffer,
@@ -728,6 +739,10 @@ where
                 (&self.alpha_tile_overlay_program.alpha_tile_program,
                  &self.alpha_tile_overlay_vertex_array)
             }
+            BlendModeProgram::DodgeBurn => {
+                (&self.alpha_tile_dodgeburn_program.alpha_tile_program,
+                 &self.alpha_tile_dodgeburn_vertex_array)
+            }
             BlendModeProgram::HSL => {
                 (&self.alpha_tile_hsl_program.alpha_tile_program,
                  &self.alpha_tile_hsl_vertex_array)
@@ -765,6 +780,11 @@ where
             BlendModeProgram::Overlay => {
                 self.set_uniforms_for_overlay_blend_mode(&mut textures, &mut uniforms, blend_mode);
             }
+            BlendModeProgram::DodgeBurn => {
+                self.set_uniforms_for_dodge_burn_blend_mode(&mut textures,  
+                                                            &mut uniforms,
+                                                            blend_mode);
+            }
             BlendModeProgram::HSL => {
                 self.set_uniforms_for_hsl_blend_mode(&mut textures, &mut uniforms, blend_mode);
             }
@@ -809,6 +829,19 @@ where
                         UniformData::TextureUnit(textures.len() as u32 - 1)));
     }
 
+    fn set_uniforms_for_dodge_burn_blend_mode<'a>(
+            &'a self,
+            textures: &mut Vec<&'a D::Texture>,
+            uniforms: &mut Vec<(&'a D::Uniform, UniformData)>,
+            blend_mode: BlendMode) {
+        uniforms.push((&self.alpha_tile_dodgeburn_program.burn_uniform,
+                       UniformData::Int(if blend_mode == BlendMode::ColorBurn { 1 } else { 0 })));
+
+        textures.push(self.device.framebuffer_texture(&self.dest_blend_framebuffer));
+        uniforms.push((&self.alpha_tile_dodgeburn_program.dest_uniform,
+                        UniformData::TextureUnit(textures.len() as u32 - 1)));
+    }
+
     fn set_uniforms_for_hsl_blend_mode<'a>(&'a self,
                                            textures: &mut Vec<&'a D::Texture>,
                                            uniforms: &mut Vec<(&'a D::Uniform, UniformData)>,
@@ -1448,6 +1481,8 @@ impl BlendModeExt for BlendMode {
             BlendMode::Screen |
             BlendMode::HardLight |
             BlendMode::Overlay |
+            BlendMode::ColorDodge |
+            BlendMode::ColorBurn |
             BlendMode::Hue |
             BlendMode::Saturation |
             BlendMode::Color |
@@ -1463,6 +1498,7 @@ impl BlendModeExt for BlendMode {
 pub(crate) enum BlendModeProgram {
     Regular,
     Overlay,
+    DodgeBurn,
     HSL,
 }
 
@@ -1482,6 +1518,8 @@ impl BlendModeProgram {
             BlendMode::Screen |
             BlendMode::HardLight |
             BlendMode::Overlay => BlendModeProgram::Overlay,
+            BlendMode::ColorDodge |
+            BlendMode::ColorBurn => BlendModeProgram::DodgeBurn,
             BlendMode::Hue |
             BlendMode::Saturation |
             BlendMode::Color |
@@ -1492,7 +1530,9 @@ impl BlendModeProgram {
     pub(crate) fn needs_readable_framebuffer(self) -> bool {
         match self {
             BlendModeProgram::Regular => false,
-            BlendModeProgram::Overlay | BlendModeProgram::HSL => true,
+            BlendModeProgram::Overlay |
+            BlendModeProgram::DodgeBurn |
+            BlendModeProgram::HSL => true,
         }
     }
 }

renderer/src/gpu/shaders.rs

@@ -484,6 +484,22 @@ impl<D> AlphaTileOverlayProgram<D> where D: Device {
     }
 }
 
+pub struct AlphaTileDodgeBurnProgram<D> where D: Device {
+    pub alpha_tile_program: AlphaTileProgram<D>,
+    pub dest_uniform: D::Uniform,
+    pub burn_uniform: D::Uniform,
+}
+
+impl<D> AlphaTileDodgeBurnProgram<D> where D: Device {
+    pub fn new(device: &D, resources: &dyn ResourceLoader) -> AlphaTileDodgeBurnProgram<D> {
+        let alpha_tile_program =
+            AlphaTileProgram::from_fragment_shader_name(device, resources, "tile_alpha_dodgeburn");
+        let dest_uniform = device.get_uniform(&alpha_tile_program.program, "Dest");
+        let burn_uniform = device.get_uniform(&alpha_tile_program.program, "Burn");
+        AlphaTileDodgeBurnProgram { alpha_tile_program, dest_uniform, burn_uniform }
+    }
+}
+
 pub struct FilterBasicProgram<D> where D: Device {
     pub program: D::Program,
     pub source_uniform: D::Uniform,

resources/shaders/gl3/tile_alpha_dodgeburn.fs.glsl

@@ -0,0 +1,86 @@
+#version {{version}}
+// Automatically generated from files in pathfinder/shaders/. Do not edit!
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+#extension GL_GOOGLE_include_directive : enable
+
+precision highp float;
+
+uniform int uBurn;
+
+out vec4 oFragColor;
+
+
+
+
+
+
+
+
+
+
+
+
+uniform sampler2D uStencilTexture;
+uniform sampler2D uPaintTexture;
+uniform sampler2D uDest;
+uniform vec2 uFramebufferSize;
+
+in vec2 vColorTexCoord;
+in vec2 vMaskTexCoord;
+
+
+vec4 sampleSrcColor(){
+    float coverage = texture(uStencilTexture, vMaskTexCoord). r;
+    vec4 srcRGBA = texture(uPaintTexture, vColorTexCoord);
+    return vec4(srcRGBA . rgb, srcRGBA . a * coverage);
+}
+
+vec4 sampleDestColor(){
+    vec2 destTexCoord = gl_FragCoord . xy / uFramebufferSize;
+    return texture(uDest, destTexCoord);
+}
+
+
+vec4 blendColors(vec4 destRGBA, vec4 srcRGBA, vec3 blendedRGB){
+    return vec4(srcRGBA . a *(1.0 - destRGBA . a)* srcRGBA . rgb +
+                srcRGBA . a * destRGBA . a * blendedRGB +
+                (1.0 - srcRGBA . a)* destRGBA . a * destRGBA . rgb,
+                1.0);
+}
+
+vec3 select3(bvec3 cond, vec3 a, vec3 b){
+    return vec3(cond . x ? a . x : b . x, cond . y ? a . y : b . y, cond . z ? a . z : b . z);
+}
+
+
+void main(){
+    vec4 srcRGBA = sampleSrcColor();
+    vec4 destRGBA = sampleDestColor();
+
+    vec3 dest = uBurn == 0 ? destRGBA . rgb : vec3(1.0)- destRGBA . rgb;
+    vec3 src = uBurn == 0 ? vec3(1.0)- srcRGBA . rgb : srcRGBA . rgb;
+
+    bvec3 srcNonzero = notEqual(src, vec3(0.0));
+    vec3 blended = min(vec3(srcNonzero . x ? dest . x / src . x : 1.0,
+                            srcNonzero . y ? dest . y / src . y : 1.0,
+                            srcNonzero . z ? dest . z / src . z : 1.0),
+                       vec3(1.0));
+    if(uBurn != 0)
+        blended = vec3(1.0)- blended;
+
+    oFragColor = blendColors(destRGBA, srcRGBA, blended);
+}
+

resources/shaders/metal/tile_alpha_dodgeburn.fs.metal

@@ -0,0 +1,114 @@
+// Automatically generated from files in pathfinder/shaders/. Do not edit!
+#pragma clang diagnostic ignored "-Wmissing-prototypes"
+
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using namespace metal;
+
+struct spvDescriptorSetBuffer0
+{
+    texture2d<float> uStencilTexture [[id(0)]];
+    sampler uStencilTextureSmplr [[id(1)]];
+    texture2d<float> uPaintTexture [[id(2)]];
+    sampler uPaintTextureSmplr [[id(3)]];
+    constant float2* uFramebufferSize [[id(4)]];
+    texture2d<float> uDest [[id(5)]];
+    sampler uDestSmplr [[id(6)]];
+    constant int* uBurn [[id(7)]];
+};
+
+struct main0_out
+{
+    float4 oFragColor [[color(0)]];
+};
+
+struct main0_in
+{
+    float2 vColorTexCoord [[user(locn0)]];
+    float2 vMaskTexCoord [[user(locn1)]];
+};
+
+float4 sampleSrcColor(thread texture2d<float> uStencilTexture, thread const sampler uStencilTextureSmplr, thread float2& vMaskTexCoord, thread texture2d<float> uPaintTexture, thread const sampler uPaintTextureSmplr, thread float2& vColorTexCoord)
+{
+    float coverage = uStencilTexture.sample(uStencilTextureSmplr, vMaskTexCoord).x;
+    float4 srcRGBA = uPaintTexture.sample(uPaintTextureSmplr, vColorTexCoord);
+    return float4(srcRGBA.xyz, srcRGBA.w * coverage);
+}
+
+float4 sampleDestColor(thread float4& gl_FragCoord, thread float2 uFramebufferSize, thread texture2d<float> uDest, thread const sampler uDestSmplr)
+{
+    float2 destTexCoord = gl_FragCoord.xy / uFramebufferSize;
+    return uDest.sample(uDestSmplr, destTexCoord);
+}
+
+float4 blendColors(thread const float4& destRGBA, thread const float4& srcRGBA, thread const float3& blendedRGB)
+{
+    return float4(((srcRGBA.xyz * (srcRGBA.w * (1.0 - destRGBA.w))) + (blendedRGB * (srcRGBA.w * destRGBA.w))) + (destRGBA.xyz * ((1.0 - srcRGBA.w) * destRGBA.w)), 1.0);
+}
+
+fragment main0_out main0(main0_in in [[stage_in]], constant spvDescriptorSetBuffer0& spvDescriptorSet0 [[buffer(0)]], float4 gl_FragCoord [[position]])
+{
+    main0_out out = {};
+    float4 srcRGBA = sampleSrcColor(spvDescriptorSet0.uStencilTexture, spvDescriptorSet0.uStencilTextureSmplr, in.vMaskTexCoord, spvDescriptorSet0.uPaintTexture, spvDescriptorSet0.uPaintTextureSmplr, in.vColorTexCoord);
+    float4 destRGBA = sampleDestColor(gl_FragCoord, (*spvDescriptorSet0.uFramebufferSize), spvDescriptorSet0.uDest, spvDescriptorSet0.uDestSmplr);
+    float3 _118;
+    if ((*spvDescriptorSet0.uBurn) == 0)
+    {
+        _118 = destRGBA.xyz;
+    }
+    else
+    {
+        _118 = float3(1.0) - destRGBA.xyz;
+    }
+    float3 dest = _118;
+    float3 _132;
+    if ((*spvDescriptorSet0.uBurn) == 0)
+    {
+        _132 = float3(1.0) - srcRGBA.xyz;
+    }
+    else
+    {
+        _132 = srcRGBA.xyz;
+    }
+    float3 src = _132;
+    bool3 srcNonzero = src != float3(0.0);
+    float _153;
+    if (srcNonzero.x)
+    {
+        _153 = dest.x / src.x;
+    }
+    else
+    {
+        _153 = 1.0;
+    }
+    float _166;
+    if (srcNonzero.y)
+    {
+        _166 = dest.y / src.y;
+    }
+    else
+    {
+        _166 = 1.0;
+    }
+    float _179;
+    if (srcNonzero.z)
+    {
+        _179 = dest.z / src.z;
+    }
+    else
+    {
+        _179 = 1.0;
+    }
+    float3 blended = fast::min(float3(_153, _166, _179), float3(1.0));
+    if ((*spvDescriptorSet0.uBurn) != 0)
+    {
+        blended = float3(1.0) - blended;
+    }
+    float4 param = destRGBA;
+    float4 param_1 = srcRGBA;
+    float3 param_2 = blended;
+    out.oFragColor = blendColors(param, param_1, param_2);
+    return out;
+}
+

shaders/Makefile

@@ -23,6 +23,7 @@ SHADERS=\
 	stencil.vs.glsl \
 	tile_alpha.fs.glsl \
 	tile_alpha.vs.glsl \
+	tile_alpha_dodgeburn.fs.glsl \
 	tile_alpha_hsl.fs.glsl \
 	tile_alpha_overlay.fs.glsl \
 	tile_copy.fs.glsl \

shaders/tile_alpha_dodgeburn.fs.glsl

@@ -0,0 +1,41 @@
+#version 330
+
+// pathfinder/shaders/tile_alpha_dodgeburn.fs.glsl
+//
+// Copyright © 2020 The Pathfinder Project Developers.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Color dodge and color burn blend modes.
+
+#extension GL_GOOGLE_include_directive : enable
+
+precision highp float;
+
+uniform int uBurn;
+
+out vec4 oFragColor;
+
+#include "tile_alpha_sample.inc.glsl"
+
+void main() {
+    vec4 srcRGBA = sampleSrcColor();
+    vec4 destRGBA = sampleDestColor();
+
+    vec3 dest = uBurn == 0 ? destRGBA.rgb : vec3(1.0) - destRGBA.rgb;
+    vec3 src  = uBurn == 0 ? vec3(1.0) - srcRGBA.rgb : srcRGBA.rgb;
+
+    bvec3 srcNonzero = notEqual(src, vec3(0.0));
+    vec3 blended = min(vec3(srcNonzero.x ? dest.x / src.x : 1.0,
+                            srcNonzero.y ? dest.y / src.y : 1.0,
+                            srcNonzero.z ? dest.z / src.z : 1.0),
+                       vec3(1.0));
+    if (uBurn != 0)
+        blended = vec3(1.0) - blended;
+
+    oFragColor = blendColors(destRGBA, srcRGBA, blended);
+}