Begin implementing VDP rendering

1 files changed, 83 insertions, 0 deletions

diff --git a/graphics.cpp b/graphics.cpp
new file mode 100644
index 0000000..2455630
--- /dev/null
+++ b/graphics.cpp
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: Unlicense
+ */
+
+#include "graphics.hpp"
+#include "vdp.hpp"
+
+#include <cstdlib>
+
+Graphics::Graphics()
+{
+#if HAS_GRAPHICS == 1
+    SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
+
+    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
+        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
+        return;
+    }
+    _window = SDL_CreateWindow("Gut (SEGA MD/G emulator)",
+                              SDL_WINDOWPOS_UNDEFINED,
+                              SDL_WINDOWPOS_UNDEFINED,
+                              VDP().render_width, VDP().render_height,
+                              SDL_WINDOW_RESIZABLE);
+    if (!_window) {
+        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't set create window: %s\n", SDL_GetError());
+        SDL_Quit();
+        return;
+    }
+    _renderer = SDL_CreateRenderer(_window, -1, 0);
+    if (!_renderer) {
+        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't set create renderer: %s\n", SDL_GetError());
+        SDL_Quit();
+        return;
+    }
+    _render_texture = SDL_CreateTexture(
+            _renderer,
+            SDL_PIXELFORMAT_ARGB8888,
+            SDL_TEXTUREACCESS_STREAMING,
+            VDP().render_width,
+            VDP().render_height);
+    if (!_render_texture) {
+        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't set create texture: %s\n", SDL_GetError());
+        SDL_Quit();
+        return;
+    }
+#endif
+    _initialized_ok = true;
+}
+
+Graphics::~Graphics()
+{
+#if HAS_GRAPHICS == 1
+    SDL_DestroyTexture(_render_texture);
+    SDL_DestroyRenderer(_renderer);
+    SDL_DestroyWindow(_window);
+    SDL_Quit();
+#endif
+}
+
+void Graphics::Render(const VDP& vdp)
+{
+    const uint8_t* buffer = vdp.GetRenderedBuffer();
+#if HAS_GRAPHICS == 1
+    void* pixels;
+    int pitch;
+    if (SDL_LockTexture(_render_texture, NULL, &pixels, &pitch) < 0) {
+        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't lock texture: %s\n", SDL_GetError());
+        abort();
+    }
+    for (int row = 0; (size_t)row < VDP().render_height; row++) {
+        uint32_t *dst = (uint32_t*)((uint8_t*)pixels + row * pitch);
+        for (int col = 0; (size_t)col < VDP().render_width; col++, buffer += 4) {
+            const uint32_t color = ((buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]);
+            *dst++ = color;
+        }
+    }
+    SDL_UnlockTexture(_render_texture);
+    SDL_RenderClear(_renderer);
+    SDL_RenderCopy(_renderer, _render_texture, NULL, NULL);
+    SDL_RenderPresent(_renderer);
+#else
+    (void) buffer;
+#endif
+}