Isolate legacy stroke composite shader setup

src/legacy_canvas_stroke_composite_services.h

@@ -0,0 +1,96 @@
+#pragma once
+
+#include "shader.h"
+#include "util.h"
+
+#include <functional>
+
+namespace pp::panopainter {
+
+struct LegacyStrokeCompositePatternUniforms {
+    glm::vec2 scale {};
+    float invert = 0.0f;
+    float brightness = 0.0f;
+    float contrast = 0.0f;
+    float depth = 0.0f;
+    int blend_mode = 0;
+    glm::vec2 offset {};
+};
+
+struct LegacyStrokeCompositeUniforms {
+    glm::vec2 resolution {};
+    LegacyStrokeCompositePatternUniforms pattern;
+    glm::mat4 mvp { 1.0f };
+    float layer_alpha = 1.0f;
+    bool alpha_lock = false;
+    bool mask_enabled = false;
+    bool use_fragcoord = false;
+    int blend_mode = 0;
+    bool use_dual = false;
+    int dual_blend_mode = 0;
+    float dual_alpha = 0.0f;
+    bool use_pattern = false;
+};
+
+struct LegacyStrokeCompositeShaderExecution {
+    std::function<void(kShader)> use_shader;
+    std::function<void(kShaderUniform, int)> set_int;
+    std::function<void(kShaderUniform, float)> set_float;
+    std::function<void(kShaderUniform, const glm::vec2&)> set_vec2;
+    std::function<void(kShaderUniform, const glm::mat4&)> set_mat4;
+};
+
+[[nodiscard]] inline LegacyStrokeCompositeShaderExecution legacy_shader_manager_stroke_composite_execution() noexcept
+{
+    return {
+        .use_shader = [](kShader shader) { ShaderManager::use(shader); },
+        .set_int = [](kShaderUniform uniform, int value) { ShaderManager::u_int(uniform, value); },
+        .set_float = [](kShaderUniform uniform, float value) { ShaderManager::u_float(uniform, value); },
+        .set_vec2 = [](kShaderUniform uniform, const glm::vec2& value) { ShaderManager::u_vec2(uniform, value); },
+        .set_mat4 = [](kShaderUniform uniform, const glm::mat4& value) { ShaderManager::u_mat4(uniform, value); },
+    };
+}
+
+inline void apply_legacy_stroke_composite_pattern_uniforms(
+    const LegacyStrokeCompositePatternUniforms& uniforms,
+    const LegacyStrokeCompositeShaderExecution& execution) noexcept
+{
+    execution.set_vec2(kShaderUniform::PatternScale, uniforms.scale);
+    execution.set_float(kShaderUniform::PatternInvert, uniforms.invert);
+    execution.set_float(kShaderUniform::PatternBright, uniforms.brightness);
+    execution.set_float(kShaderUniform::PatternContrast, uniforms.contrast);
+    execution.set_float(kShaderUniform::PatternDepth, uniforms.depth);
+    execution.set_int(kShaderUniform::PatternBlendMode, uniforms.blend_mode);
+    execution.set_vec2(kShaderUniform::PatternOffset, uniforms.offset);
+}
+
+inline void setup_legacy_stroke_composite_shader(
+    const LegacyStrokeCompositeUniforms& uniforms,
+    const LegacyStrokeCompositeShaderExecution& execution) noexcept
+{
+    execution.use_shader(kShader::CompDraw);
+    execution.set_int(kShaderUniform::Tex, 0);
+    execution.set_int(kShaderUniform::TexStroke, 1);
+    execution.set_int(kShaderUniform::TexMask, 2);
+    execution.set_int(kShaderUniform::TexDual, 3);
+    execution.set_int(kShaderUniform::TexPattern, 4);
+    execution.set_vec2(kShaderUniform::Resolution, uniforms.resolution);
+    execution.set_float(kShaderUniform::Alpha, uniforms.layer_alpha);
+    execution.set_int(kShaderUniform::Lock, uniforms.alpha_lock);
+    execution.set_int(kShaderUniform::Mask, uniforms.mask_enabled);
+    execution.set_int(kShaderUniform::UseFragcoord, uniforms.use_fragcoord);
+    execution.set_int(kShaderUniform::BlendMode, uniforms.blend_mode);
+    execution.set_mat4(kShaderUniform::MVP, uniforms.mvp);
+    execution.set_int(kShaderUniform::UseDual, uniforms.use_dual);
+    execution.set_int(kShaderUniform::UsePattern, uniforms.use_pattern);
+    execution.set_int(kShaderUniform::DualBlendMode, uniforms.dual_blend_mode);
+    apply_legacy_stroke_composite_pattern_uniforms(uniforms.pattern, execution);
+    execution.set_float(kShaderUniform::DualAlpha, uniforms.dual_alpha);
+}
+
+inline void setup_legacy_stroke_composite_shader(const LegacyStrokeCompositeUniforms& uniforms)
+{
+    setup_legacy_stroke_composite_shader(uniforms, legacy_shader_manager_stroke_composite_execution());
+}
+
+} // namespace pp::panopainter