feat(shaders): sistema de shaders runtime amb presets externs

- Afegir GpuShaderPreset i ShaderManager per carregar shaders des de data/shaders/ - Implementar preset ntsc-md-rainbows (2 passos: encode + decode MAME NTSC) - Render loop multi-pass per shaders externs (targets intermedis R16G16B16A16_FLOAT) - cycleShader(): cicla OFF→PostFX natius→shaders externs amb tecla X - --shader <nom> per arrancar directament amb un preset extern - CMake auto-descubreix i compila data/shaders/**/*.vert/.frag → .spv - HUD F1 mostra 'Shader: <nom>' quan hi ha shader extern actiu Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-03-20 13:37:22 +01:00
parent e3f29c864b
commit f272bab296
19 changed files with 1004 additions and 23 deletions
--- a/source/gpu/shader_manager.cpp
+++ b/source/gpu/shader_manager.cpp
@@ -0,0 +1,68 @@
+#include "shader_manager.hpp"
+
+#include <SDL3/SDL_log.h>
+#include <filesystem>
+#include <algorithm>
+
+namespace fs = std::filesystem;
+
+void ShaderManager::scan(const std::string& root_dir) {
+    root_dir_ = root_dir;
+    names_.clear();
+    dirs_.clear();
+
+    std::error_code ec;
+    for (const auto& entry : fs::directory_iterator(root_dir, ec)) {
+        if (!entry.is_directory()) continue;
+        fs::path ini = entry.path() / "preset.ini";
+        if (!fs::exists(ini)) continue;
+
+        std::string preset_name = entry.path().filename().string();
+        names_.push_back(preset_name);
+        dirs_[preset_name] = entry.path().string();
+    }
+
+    if (ec) {
+        SDL_Log("ShaderManager: scan error on %s: %s", root_dir.c_str(), ec.message().c_str());
+    }
+
+    std::sort(names_.begin(), names_.end());
+    SDL_Log("ShaderManager: found %d preset(s) in %s", (int)names_.size(), root_dir.c_str());
+}
+
+GpuShaderPreset* ShaderManager::load(SDL_GPUDevice* device,
+                                      const std::string& name,
+                                      SDL_GPUTextureFormat swapchain_fmt,
+                                      int w, int h) {
+    auto it = loaded_.find(name);
+    if (it != loaded_.end()) return it->second.get();
+
+    auto dir_it = dirs_.find(name);
+    if (dir_it == dirs_.end()) {
+        SDL_Log("ShaderManager: preset '%s' not found", name.c_str());
+        return nullptr;
+    }
+
+    auto preset = std::make_unique<GpuShaderPreset>();
+    if (!preset->load(device, dir_it->second, swapchain_fmt, w, h)) {
+        SDL_Log("ShaderManager: failed to load preset '%s'", name.c_str());
+        return nullptr;
+    }
+
+    GpuShaderPreset* raw = preset.get();
+    loaded_[name] = std::move(preset);
+    return raw;
+}
+
+void ShaderManager::onResize(SDL_GPUDevice* device, SDL_GPUTextureFormat /*swapchain_fmt*/, int w, int h) {
+    for (auto& [name, preset] : loaded_) {
+        preset->recreateTargets(device, w, h);
+    }
+}
+
+void ShaderManager::destroyAll(SDL_GPUDevice* device) {
+    for (auto& [name, preset] : loaded_) {
+        preset->destroy(device);
+    }
+    loaded_.clear();
+}