create ffbg

1 files changed, 98 insertions, 0 deletions

diff --git a/drw.c b/drw.c
new file mode 100644
index 0000000..b78d10a
--- /dev/null
+++ b/drw.c
@@ -0,0 +1,98 @@
+#include <sys/mman.h>
+#include <unistd.h>
+#include <math.h>
+#include <stdlib.h>
+
+#include "drw.h"
+#include "util.h"
+
+/* static function declarations */
+static Color to_color(uint32_t color);
+static uint32_t to_uint32_t(Color color);
+
+
+Canvas*
+create_drw(struct wl_shm *shm, unsigned width, unsigned height)
+{
+	struct wl_shm_pool *pool;
+	Canvas *canvas;
+	int stride;
+	int fd;
+
+	canvas = malloc(sizeof(Canvas));
+	canvas->width = width;
+	canvas->height = height;
+
+	stride = width * sizeof(uint32_t);
+	canvas->size = stride * height;
+
+	fd = allocate_shm_file(canvas->size);
+	if (fd == -1) {
+		return NULL;
+	}
+
+	canvas->data = mmap(
+			NULL,
+			canvas->size,
+			PROT_READ | PROT_WRITE,
+			MAP_SHARED,
+			fd,
+			0
+		);
+
+	if (canvas->data == MAP_FAILED) {
+		close(fd);
+		return NULL;
+	}
+
+	pool = wl_shm_create_pool(
+			shm,
+			fd,
+			canvas->size
+	);
+
+	canvas->buffer = wl_shm_pool_create_buffer(
+			pool,
+			0,
+			width,
+			height,
+			stride,
+			WL_SHM_FORMAT_XRGB8888
+		);
+
+	wl_shm_pool_destroy(pool);
+	close(fd);
+
+	return canvas;
+}
+
+
+void
+free_drw(Canvas *canvas)
+{
+	munmap(canvas->data, canvas->size);
+	free(canvas);
+}
+
+
+void
+draw_point(Canvas *canvas, unsigned x, unsigned y, uint32_t color)
+{
+	if (!(x < canvas->width && y < canvas->height))
+		return;
+
+	canvas->data[x + canvas->width * y] = color;
+}
+
+
+void
+draw_rect(Canvas *canvas, unsigned x, unsigned y, unsigned width, unsigned height, uint32_t color) {
+	int py;
+	int px;
+
+	for (py = y; py < y + height; ++py) {
+		for (px = x; px < x + width; ++px) {
+			draw_point(canvas, px, py, color);
+		}
+	}
+}