cool kid upscale

1 files changed, 30 insertions, 2 deletions

diff --git a/src/orgaemu.c b/src/orgaemu.c
index 4b7630e..7de0334 100644
--- a/src/orgaemu.c
+++ b/src/orgaemu.c
@@ -10,10 +10,13 @@ static uint16_t *mem = NULL, *stack = NULL, *rstack = NULL;
 static size_t stack_ptr = 0, rstack_ptr = 0;
 static SDL_Window *window = NULL;
 static SDL_Renderer *renderer = NULL;
+static SDL_Texture *target = NULL;
 
 static int
 fail(void)
 {
+	if (target != NULL)
+		SDL_DestroyTexture(target);
 	if (renderer != NULL)
 		SDL_DestroyRenderer(renderer);
 	if (window != NULL)
@@ -52,6 +55,20 @@ cycle_events(void)
 static void
 render(uint16_t *mem)
 {
+	int win_w, win_h;
+	SDL_GetWindowSize(window, &win_w, &win_h);
+	win_w = win_w ? win_w : 1;
+	win_h = win_h ? win_h : 1;
+	const float ratio_w = win_w / 128.0;
+	const float ratio_h = win_h / 128.0;
+	float scale = (ratio_w < ratio_h) ? ratio_w : ratio_h;
+	if (scale > 1.0)
+		scale = (int)scale;
+	const int off_x = (win_w - 128 * scale) / 2;
+	const int off_y = (win_h - 128 * scale) / 2;
+	const SDL_Rect dest = { off_x, off_y, 128 * scale, 128 * scale };
+
+	SDL_SetRenderTarget(renderer, target);
 	SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
 	SDL_RenderClear(renderer);
 	for (int y = 0; y < 128; y++) {
@@ -66,8 +83,12 @@ render(uint16_t *mem)
 			SDL_RenderDrawPoint(renderer, x, y);
 		}
 	}
+	SDL_SetRenderTarget(renderer, NULL);
+	SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
+	SDL_RenderClear(renderer);
+	SDL_RenderCopy(renderer, target, NULL, &dest);
 	SDL_RenderPresent(renderer);
-	SDL_Delay(1000 / 30);
+	SDL_Delay(1000 / 30); /* TODO: proper fps cap */
 }
 
 static void
@@ -331,7 +352,14 @@ main(int argc, char **argv)
 		fprintf(stderr, "%s\n", SDL_GetError());
 		return fail();
 	}
-	if (SDL_CreateWindowAndRenderer(128, 128, 0, &window, &renderer) < 0) {
+	if (SDL_CreateWindowAndRenderer(128, 128, SDL_WINDOW_RESIZABLE,
+	                                &window, &renderer) < 0) {
+		fprintf(stderr, "%s\n", SDL_GetError());
+		return fail();
+	}
+	target = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGB888,
+	                           SDL_TEXTUREACCESS_TARGET, 128, 128);
+	if (target == NULL) {
 		fprintf(stderr, "%s\n", SDL_GetError());
 		return fail();
 	}