Adds XRGB8888 core support

Simple version, conversion can still be optimized

1 files changed, 78 insertions, 0 deletions

diff --git a/video.c b/video.c
new file mode 100644
index 0000000..99ac2a6
--- /dev/null
+++ b/video.c
@@ -0,0 +1,78 @@
+#include "video.h"
+#include "main.h"
+#include "plat.h"
+
+static struct {
+	unsigned max_width;
+	unsigned max_height;
+	enum retro_pixel_format pixel_format;
+	uint16_t *buffer;
+} screen_def;
+
+static void video_alloc_convert_buffer(
+	unsigned new_width,
+	unsigned new_height,
+	enum retro_pixel_format new_format
+) {
+	if (new_width == screen_def.max_width &&
+	    new_height == screen_def.max_height &&
+	    new_format == screen_def.pixel_format)
+		return;
+
+	if (screen_def.buffer) {
+		free(screen_def.buffer);
+		screen_def.buffer = NULL;
+	}
+
+	if ((new_width > 0 || new_height > 0) && new_format == RETRO_PIXEL_FORMAT_XRGB8888) {
+		screen_def.buffer = malloc(new_width * new_height * sizeof(uint16_t));
+		if (!screen_def.buffer)
+			PA_FATAL("Can't allocate buffer for color format conversion\n");
+	}
+}
+
+void video_set_geometry(struct retro_game_geometry *geometry) {
+	video_alloc_convert_buffer(geometry->max_width,
+	                           geometry->max_height,
+	                           screen_def.pixel_format);
+
+	screen_def.max_width = geometry->max_width;
+	screen_def.max_height = geometry->max_height;
+}
+
+void video_set_pixel_format(enum retro_pixel_format format) {
+	video_alloc_convert_buffer(screen_def.max_width,
+	                           screen_def.max_height,
+	                           format);
+
+	screen_def.pixel_format = format;
+}
+
+void video_process(const void *data, unsigned width, unsigned height, size_t pitch) {
+	const uint32_t *input = data;
+	uint16_t *output = screen_def.buffer;
+	size_t extra = pitch / sizeof(uint32_t) - width;
+
+	if (screen_def.pixel_format != RETRO_PIXEL_FORMAT_XRGB8888)
+		return plat_video_process(data, width, height, pitch);
+
+	for (int y = 0; y < height; y++) {
+		for (int x = 0; x < width; x++) {
+			*output =  (*input & 0xF80000) >> 8;
+			*output |= (*input & 0xFC00) >> 5;
+			*output |= (*input & 0xF8) >> 3;
+			input++;
+			output++;
+		}
+
+		input += extra;
+	}
+
+	plat_video_process(screen_def.buffer, width, height, width * sizeof(uint16_t));
+}
+
+void video_deinit(void) {
+	free(screen_def.buffer);
+	screen_def.buffer = NULL;
+}
+