[PATCH weston] compositor-drm: calculate source rect using viewport top-left for sprite plane

[Tomohito Esaki]

Add the viewport offset position into the sprite plane cropping
calculation. Without this patch the sprite plane always outputs from the
top left corner of the source buffer.

Signed-off-by: Tomohito Esaki <etom at igel.co.jp>
---
 libweston/compositor-drm.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/libweston/compositor-drm.c b/libweston/compositor-drm.c
index 8319d7c..31f9724 100644
--- a/libweston/compositor-drm.c
+++ b/libweston/compositor-drm.c
@@ -1105,6 +1105,19 @@ drm_output_prepare_overlay_view(struct drm_output *output,
 	if (sy2 > wl_fixed_from_int(ev->surface->height))
 		sy2 = wl_fixed_from_int(ev->surface->height);
 
+	/* Calculate source crop offset */
+	if (viewport->buffer.src_width != wl_fixed_from_int(-1) &&
+	    viewport->buffer.src_height != wl_fixed_from_int(-1)) {
+		if (sx1 < viewport->buffer.src_x) {
+			sx1 = viewport->buffer.src_x;
+			sx2 += sx1;
+		}
+		if (sy1 < viewport->buffer.src_y) {
+			sy1 = viewport->buffer.src_y;
+			sy2 += sy1;
+		}
+	}
+
 	tbox.x1 = sx1;
 	tbox.y1 = sy1;
 	tbox.x2 = sx2;
-- 
2.7.4