fb: implement a tiling fragmenter

2 files changed, 35 insertions, 0 deletions

diff --git a/src/fb.c b/src/fb.c
index c3ed1ed..250bd37 100644
--- a/src/fb.c
+++ b/src/fb.c
@@ -342,3 +342,37 @@ int fb_fragment_divide_single(const fb_fragment_t *fragment, unsigned n_fragment
 
 	return 1;
 }
+
+
+int fb_fragment_tile_single(const fb_fragment_t *fragment, unsigned tile_size, unsigned num, fb_fragment_t *res_fragment)
+{
+	unsigned	w = fragment->width / tile_size, h = fragment->height / tile_size;
+	unsigned	pitch = (fragment->width * 4) + fragment->stride;
+	unsigned	x, y, xoff, yoff;
+
+	if (w * tile_size < fragment->width)
+		w++;
+
+	if (h * tile_size < fragment->height)
+		h++;
+
+	y = num / w;
+	if (y >= h)
+		return 0;
+
+	x = num - (y * w);
+
+	xoff = x * tile_size;
+	yoff = y * tile_size;
+
+	res_fragment->buf = (void *)fragment->buf + (yoff * pitch) + (xoff * 4);
+	res_fragment->x = fragment->x + xoff;
+	res_fragment->y = fragment->y + yoff;
+	res_fragment->width = MIN(fragment->width - xoff, tile_size);
+	res_fragment->height = MIN(fragment->height - yoff, tile_size);
+	res_fragment->frame_width = fragment->frame_width;
+	res_fragment->frame_height = fragment->frame_height;
+	res_fragment->stride = fragment->stride + ((fragment->width - res_fragment->width) * 4);
+
+	return 1;
+}
diff --git a/src/fb.h b/src/fb.h
index 35d5865..055c609 100644
--- a/src/fb.h
+++ b/src/fb.h
@@ -37,6 +37,7 @@ void fb_get_put_pages_count(fb_t *fb, unsigned *count);
 fb_t * fb_new(int drm_fd, uint32_t crtc_id, uint32_t *connectors, int n_connectors, drmModeModeInfoPtr mode, int n_pages);
 void fb_fragment_divide(fb_fragment_t *fragment, unsigned n_fragments, fb_fragment_t fragments[]);
 int fb_fragment_divide_single(const fb_fragment_t *fragment, unsigned n_fragments, unsigned num, fb_fragment_t *res_fragment);
+int fb_fragment_tile_single(const fb_fragment_t *fragment, unsigned tile_size, unsigned num, fb_fragment_t *res_fragment);
 
 
 /* checks if a coordinate is contained within a fragment */