From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 13 Dec 2015 12:27:12 +0000 (+0200)
Subject: Clear damage before rendering the window
X-Git-Url: http://git.tdb.fi/?p=geometrycompositor.git;a=commitdiff_plain;h=19993ceafcc8e63da2f4cbfed71324434b5dfacc

Clear damage before rendering the window

This avoids a race condition where the application might render to the
window after it has been rendered but before the damage is cleared.
---

diff --git a/source/main.c b/source/main.c
index 1cabcf6..074477b 100644
--- a/source/main.c
+++ b/source/main.c
@@ -1069,6 +1069,8 @@ void refresh_screen(Compositor *compositor, CompositedScreen *screen)
 		if(window->map_state!=IsViewable)
 			continue;
 
+		XDamageSubtract(compositor->display, window->damage, None, None);
+
 		glBindTexture(GL_TEXTURE_2D, window->texture);
 		compositor->glXBindTexImageEXT(compositor->display, window->glx_pixmap, GLX_FRONT_LEFT_EXT, NULL);
 		glUniform4f(screen->geometry_loc,
@@ -1076,7 +1078,6 @@ void refresh_screen(Compositor *compositor, CompositedScreen *screen)
 			(float)(window->width+2*window->border)/screen->width, (float)(window->height+2*window->border)/screen->height);
 		glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
 		compositor->glXReleaseTexImageEXT(compositor->display, window->glx_pixmap, GLX_FRONT_LEFT_EXT);
-		XDamageSubtract(compositor->display, window->damage, None, None);
 	}
 
 	glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);