feat: post-processing effects

res/preload.json

@@ -5,10 +5,12 @@
         "main",
         "lines",
         "entity",
-        "screen",
         "background",
         "skybox_gen"
     ],
+    "post-effects": [
+        "default"
+    ],
     "textures": [
         "gui/menubg",
         "gui/delete_icon",

res/shaders/effect.glslf

@@ -0,0 +1,13 @@
+in vec2 v_uv;
+out vec4 f_color;
+
+uniform sampler2D u_screen;
+uniform ivec2 u_screenSize;
+uniform float u_intensity;
+
+#include <__effect__>
+
+void main() {
+    f_color = effect();
+}
+

res/shaders/effect.glslv

@@ -1,13 +1,10 @@
 layout (location = 0) in vec2 v_position;
 
-out vec2 v_coord;
+out vec2 v_uv;
 
 uniform ivec2 u_screenSize;
-uniform float u_timer;
-uniform float u_dayTime;
 
 void main(){
-    v_coord = v_position * 0.5 + 0.5;
+    v_uv = v_position * 0.5 + 0.5;
     gl_Position = vec4(v_position, 0.0, 1.0);
 }
-

res/shaders/effects/default.glsl

@@ -0,0 +1,3 @@
+vec4 effect() {
+    return texture(u_screen, v_uv);
+}

res/shaders/screen.glslf

@@ -1,25 +0,0 @@
-in vec2 v_coord;
-out vec4 f_color;
-
-uniform sampler2D u_texture0;
-uniform ivec2 u_screenSize;
-
-// Vignette
-vec4 apply_vignette(vec4 color) {
-    vec2 position = (gl_FragCoord.xy / u_screenSize) - vec2(0.5);
-    float dist = length(position);
-
-    float radius = 1.3;
-    float softness = 1.0;
-    float vignette = smoothstep(radius, radius - softness, dist);
-
-    color.rgb = color.rgb * vignette;
-
-    return color;
-}
-
-void main() {
-    f_color = texture(u_texture0, v_coord);
-    f_color = apply_vignette(f_color);
-}
-

src/assets/Assets.hpp

@@ -16,7 +16,16 @@
 
 class Assets;
 
-enum class AssetType { TEXTURE, SHADER, FONT, ATLAS, LAYOUT, SOUND, MODEL };
+enum class AssetType {
+    TEXTURE,
+    SHADER,
+    FONT,
+    ATLAS,
+    LAYOUT,
+    SOUND,
+    MODEL,
+    POST_EFFECT
+};
 
 namespace assetload {
     /// @brief final work to do in the main thread
@@ -91,6 +100,20 @@ public:
         return static_cast<T*>(found->second.get());
     }
 
+    template <class T>
+    std::shared_ptr<T> getShared(const std::string& name) const {
+        const auto& mapIter = assets.find(typeid(T));
+        if (mapIter == assets.end()) {
+            return nullptr;
+        }
+        const auto& map = mapIter->second;
+        const auto& found = map.find(name);
+        if (found == map.end()) {
+            return nullptr;
+        }
+        return std::static_pointer_cast<T>(found->second);
+    }
+
     template <class T>
     T& require(const std::string& name) const {
         T* asset = get<T>(name);

src/assets/AssetsLoader.cpp

@@ -34,6 +34,7 @@ AssetsLoader::AssetsLoader(Engine& engine, Assets& assets, const ResPaths& paths
     addLoader(AssetType::LAYOUT, assetload::layout);
     addLoader(AssetType::SOUND, assetload::sound);
     addLoader(AssetType::MODEL, assetload::model);
+    addLoader(AssetType::POST_EFFECT, assetload::posteffect);
 }
 
 void AssetsLoader::addLoader(AssetType tag, aloader_func func) {
@@ -131,6 +132,8 @@ static std::string assets_def_folder(AssetType tag) {
             return SOUNDS_FOLDER;
         case AssetType::MODEL:
             return MODELS_FOLDER;
+        case AssetType::POST_EFFECT:
+            return POST_EFFECTS_FOLDER;
     }
     return "<error>";
 }
@@ -196,6 +199,7 @@ void AssetsLoader::processPreloadConfig(const io::path& file) {
     processPreloadList(AssetType::TEXTURE, root["textures"]);
     processPreloadList(AssetType::SOUND, root["sounds"]);
     processPreloadList(AssetType::MODEL, root["models"]);
+    processPreloadList(AssetType::POST_EFFECT, root["post-effects"]);
     // layouts are loaded automatically
 }
 

src/assets/assetload_funcs.cpp

@@ -60,13 +60,7 @@ assetload::postfunc assetload::texture(
     }
 }
 
-assetload::postfunc assetload::shader(
-    AssetsLoader*,
-    const ResPaths& paths,
-    const std::string& filename,
-    const std::string& name,
-    const std::shared_ptr<AssetCfg>&
-) {
+static auto process_program(const ResPaths& paths, const std::string& filename) {
     io::path vertexFile = paths.find(filename + ".glslv");
     io::path fragmentFile = paths.find(filename + ".glslf");
 
@@ -75,8 +69,25 @@ assetload::postfunc assetload::shader(
 
     auto& preprocessor = *Shader::preprocessor;
 
-    vertexSource = preprocessor.process(vertexFile, vertexSource).code;
-    fragmentSource = preprocessor.process(fragmentFile, fragmentSource).code;
+    auto vertex = preprocessor.process(vertexFile, vertexSource);
+    auto fragment = preprocessor.process(fragmentFile, fragmentSource);
+    return std::make_pair(vertex, fragment);
+}
+
+assetload::postfunc assetload::shader(
+    AssetsLoader*,
+    const ResPaths& paths,
+    const std::string& filename,
+    const std::string& name,
+    const std::shared_ptr<AssetCfg>&
+) {
+    auto [vertex, fragment] = process_program(paths, filename);
+
+    io::path vertexFile = paths.find(filename + ".glslv");
+    io::path fragmentFile = paths.find(filename + ".glslf");
+
+    std::string vertexSource = std::move(vertex.code);
+    std::string fragmentSource = std::move(fragment.code);
 
     return [=](auto assets) {
         assets->store(
@@ -91,6 +102,40 @@ assetload::postfunc assetload::shader(
     };
 }
 
+assetload::postfunc assetload::posteffect(
+    AssetsLoader*,
+    const ResPaths& paths,
+    const std::string& file,
+    const std::string& name,
+    const std::shared_ptr<AssetCfg>& settings
+) {
+    io::path effectFile = paths.find(file + ".glsl");
+    std::string effectSource = io::read_string(effectFile);
+
+    auto& preprocessor = *Shader::preprocessor;
+    preprocessor.addHeader(
+        "__effect__", preprocessor.process(effectFile, effectSource, true)
+    );
+
+    auto [vertex, fragment] = process_program(paths, SHADERS_FOLDER + "/effect");
+    auto params = std::move(fragment.params);
+
+    std::string vertexSource = std::move(vertex.code);
+    std::string fragmentSource = std::move(fragment.code);
+
+    return [=](auto assets) {
+        auto program = Shader::create(
+            effectFile.string(),
+            effectFile.string(),
+            vertexSource,
+            fragmentSource
+        );
+        assets->store(
+            std::make_shared<PostEffect>(std::move(program), params), name
+        );
+    };
+}
+
 static bool append_atlas(AtlasBuilder& atlas, const io::path& file) {
     std::string name = file.stem();
     // skip duplicates

src/assets/assetload_funcs.hpp

@@ -62,4 +62,11 @@ namespace assetload {
         const std::string& name,
         const std::shared_ptr<AssetCfg>& settings
     );
+    postfunc posteffect(
+        AssetsLoader*,
+        const ResPaths& paths,
+        const std::string& file,
+        const std::string& name,
+        const std::shared_ptr<AssetCfg>& settings
+    );
 }

src/coders/GLSLExtension.cpp

@@ -27,21 +27,21 @@ void GLSLExtension::loadHeader(const std::string& name) {
     }
     io::path file = paths->find("shaders/lib/" + name + ".glsl");
     std::string source = io::read_string(file);
-    addHeader(name, "");
-
-    auto [code, _] = process(file, source, true);
-    addHeader(name, std::move(code));
+    addHeader(name, {});
+    addHeader(name, process(file, source, true));
 }
 
-void GLSLExtension::addHeader(const std::string& name, std::string source) {
-    headers[name] = std::move(source);
+void GLSLExtension::addHeader(const std::string& name, ProcessingResult header) {
+    headers[name] = std::move(header);
 }
 
 void GLSLExtension::define(const std::string& name, std::string value) {
     defines[name] = std::move(value);
 }
 
-const std::string& GLSLExtension::getHeader(const std::string& name) const {
+const GLSLExtension::ProcessingResult& GLSLExtension::getHeader(
+    const std::string& name
+) const {
     auto found = headers.find(name);
     if (found == headers.end()) {
         throw std::runtime_error("no header '" + name + "' loaded");
@@ -161,7 +161,11 @@ public:
         if (!glsl.hasHeader(headerName)) {
             glsl.loadHeader(headerName);
         }
-        ss << glsl.getHeader(headerName) << '\n';
+        const auto& header = glsl.getHeader(headerName);
+        for (const auto& [name, param] : header.params) {
+            params[name] = param;
+        }
+        ss << header.code << '\n';
         source_line(ss, line);
         return false;
     }

src/coders/GLSLExtension.hpp

@@ -11,13 +11,20 @@ class ResPaths;
 
 class GLSLExtension {
 public:
+    using ParamsMap = std::unordered_map<std::string, PostEffect::Param>;
+
+    struct ProcessingResult {
+        std::string code;
+        ParamsMap params;
+    };
+
     void setPaths(const ResPaths* paths);
 
     void define(const std::string& name, std::string value);
     void undefine(const std::string& name);
-    void addHeader(const std::string& name, std::string source);
+    void addHeader(const std::string& name, ProcessingResult header);
 
-    const std::string& getHeader(const std::string& name) const;
+    const ProcessingResult& getHeader(const std::string& name) const;
     const std::string& getDefine(const std::string& name) const;
 
     const std::unordered_map<std::string, std::string>& getDefines() const;
@@ -25,12 +32,7 @@ public:
     bool hasHeader(const std::string& name) const;
     bool hasDefine(const std::string& name) const;
     void loadHeader(const std::string& name);
-
-    struct ProcessingResult {
-        std::string code;
-        std::unordered_map<std::string, PostEffect::Param> params;
-    };
-
+    
     ProcessingResult process(
         const io::path& file,
         const std::string& source,
@@ -39,7 +41,7 @@ public:
 
     static inline std::string VERSION = "330 core";
 private:
-    std::unordered_map<std::string, std::string> headers;
+    std::unordered_map<std::string, ProcessingResult> headers;
     std::unordered_map<std::string, std::string> defines;
 
     const ResPaths* paths = nullptr;

src/constants.hpp

@@ -68,5 +68,6 @@ inline const std::string LAYOUTS_FOLDER = "layouts";
 inline const std::string SOUNDS_FOLDER = "sounds";
 inline const std::string MODELS_FOLDER = "models";
 inline const std::string SKELETONS_FOLDER = "skeletons";
+inline const std::string POST_EFFECTS_FOLDER = "shaders/effects";
 
 inline const std::string FONT_DEFAULT = "normal";

src/graphics/core/PostEffect.cpp

@@ -8,10 +8,19 @@ PostEffect::Param::Param(Type type, Value defValue)
     : type(type), defValue(std::move(defValue)) {
 }
 
-PostEffect::PostEffect(std::unique_ptr<Shader> shader)
-    : shader(std::move(shader)) {
+PostEffect::PostEffect(
+    std::unique_ptr<Shader> shader,
+    std::unordered_map<std::string, Param> params
+)
+    : shader(std::move(shader)), params(std::move(params)) {
 }
 
-void PostEffect::use() {
+Shader& PostEffect::use() {
     shader->use();
+    shader->uniform1f("u_intensity", intensity);
+    return *shader;
+}
+
+void PostEffect::setIntensity(float value) {
+    intensity = value;
 }

src/graphics/core/PostEffect.hpp

@@ -21,10 +21,20 @@ public:
         Param(Type type, Value defValue);
     };
 
-    PostEffect(std::unique_ptr<Shader> shader);
+    PostEffect(
+        std::unique_ptr<Shader> shader,
+        std::unordered_map<std::string, Param> params
+    );
 
-    void use();
+    Shader& use();
+
+    void setIntensity(float value);
+
+    bool isActive() {
+        return intensity > 1e-4f;
+    }
 private:
     std::unique_ptr<Shader> shader;
     std::unordered_map<std::string, Param> params;
+    float intensity = 0.0f;
 };

src/graphics/core/PostProcessing.cpp

@@ -4,13 +4,15 @@
 #include "Texture.hpp"
 #include "Framebuffer.hpp"
 #include "DrawContext.hpp"
+#include "PostEffect.hpp"
+#include "assets/Assets.hpp"
 
 #include <stdexcept>
 
 PostProcessing::PostProcessing() {
     // Fullscreen quad mesh bulding
     float vertices[] {
-        -1.0f, -1.0f, -1.0f, 1.0f, 1.0f, 1.0f,
+        -1.0f, -1.0f, -1.0f, 1.0f, 1.0f,  1.0f,
         -1.0f, -1.0f,  1.0f, 1.0f, 1.0f, -1.0f
     };
     VertexAttribute attrs[] {{2}, {0}};
@@ -23,22 +25,56 @@ void PostProcessing::use(DrawContext& context) {
     const auto& vp = context.getViewport();
     if (fbo) {
         fbo->resize(vp.x, vp.y);
+        fboSecond->resize(vp.x, vp.y);
     } else {
         fbo = std::make_unique<Framebuffer>(vp.x, vp.y);
+        fboSecond = std::make_unique<Framebuffer>(vp.x, vp.y);
     }
     context.setFramebuffer(fbo.get());
 }
 
-void PostProcessing::render(const DrawContext& context, Shader* screenShader) {
+void PostProcessing::render(
+    const DrawContext& context, const Assets& assets, float timer
+) {
     if (fbo == nullptr) {
         throw std::runtime_error("'use(...)' was never called");
     }
+    int totalPasses = 0;
+    for (const auto& effect : effectSlots) {
+        totalPasses += (effect != nullptr && effect->isActive());
+    }
 
-    const auto& viewport = context.getViewport();
-    screenShader->use();
-    screenShader->uniform2i("u_screenSize", viewport);
-    fbo->getTexture()->bind();
-    quadMesh->draw();
+    if (totalPasses == 0) {
+        auto& effect = assets.require<PostEffect>("default");
+        effect.use();
+        fbo->getTexture()->bind();
+        quadMesh->draw();
+        return;
+    }
+
+    int currentPass = 1;
+    for (const auto& effect : effectSlots) {
+        if (effect == nullptr || !effect->isActive()) {
+            continue;
+        }
+        auto& shader = effect->use();
+
+        const auto& viewport = context.getViewport();
+        shader.uniform1i("u_screen", 0);
+        shader.uniform2i("u_screenSize", viewport);
+        shader.uniform1f("u_timer", timer);
+
+        fbo->getTexture()->bind();
+        if (currentPass < totalPasses) {
+            fboSecond->bind();
+        }
+        quadMesh->draw();
+        if (currentPass < totalPasses) {
+            fboSecond->unbind();
+            std::swap(fbo, fboSecond);
+        }
+        currentPass++;
+    }
 }
 
 std::unique_ptr<ImageData> PostProcessing::toImage() {

src/graphics/core/PostProcessing.hpp

@@ -1,12 +1,14 @@
 #pragma once
 
+#include <vector>
 #include <memory>
 
 class Mesh;
-class Shader;
+class Assets;
 class Framebuffer;
 class DrawContext;
 class ImageData;
+class PostEffect;
 
 /// @brief Framebuffer with blitting with shaders.
 /// @attention Current implementation does not support multiple render passes 
@@ -14,8 +16,10 @@ class ImageData;
 class PostProcessing {
     /// @brief Main framebuffer (lasy field)
     std::unique_ptr<Framebuffer> fbo;
+    std::unique_ptr<Framebuffer> fboSecond;
     /// @brief Fullscreen quad mesh as the post-processing canvas
     std::unique_ptr<Mesh> quadMesh;
+    std::vector<std::shared_ptr<PostEffect>> effectSlots;
 public:
     PostProcessing();
     ~PostProcessing();
@@ -27,9 +31,8 @@ public:
     /// @brief Render fullscreen quad using the passed shader 
     /// with framebuffer texture bound
     /// @param context graphics context
-    /// @param screenShader shader used for fullscreen quad
     /// @throws std::runtime_error if use(...) wasn't called before
-    void render(const DrawContext& context, Shader* screenShader);
+    void render(const DrawContext& context, const Assets& assets, float timer);
 
     /// @brief Make an image from the last rendered frame
     std::unique_ptr<ImageData> toImage();

src/graphics/render/WorldRenderer.cpp

@@ -388,12 +388,7 @@ void WorldRenderer::draw(
         renderBlockOverlay(wctx);
     }
 
-    // Rendering fullscreen quad
-    auto screenShader = assets.get<Shader>("screen");
-    screenShader->use();
-    screenShader->uniform1f("u_timer", timer);
-    screenShader->uniform1f("u_dayTime", worldInfo.daytime);
-    postProcessing.render(pctx, screenShader);
+    postProcessing.render(pctx, assets, timer);
 }
 
 void WorldRenderer::renderBlockOverlay(const DrawContext& wctx) {

src/typedefs.hpp

@@ -1,7 +1,7 @@
 #pragma once
 
 #include <memory>
-#include <stdint.h>
+#include <cstdint>
 
 using scriptenv = std::shared_ptr<int>;
 

test/coders/GLSLExtension.cpp

@@ -6,10 +6,13 @@
 TEST(GLSLExtension, processing) {
     GLSLExtension glsl;
     glsl.addHeader("sum", 
-        "// sum function for glsl\n"
-        "float sum(float a, float b) {\n"
-        "    return a + b;\n"
-        "}\n"
+        glsl.process("sum.glsl",
+            "// sum function for glsl\n"
+            "float sum(float a, float b) {\n"
+            "    return a + b;\n"
+            "}\n",
+            true
+        )
     );
     try {
         auto processed = glsl.process("test.glsl",