egl-helpers: add alpha channel to texture format

Needed when rendering cursers which (unlike framebuffers)
actually are transparent.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20180220110433.20353-4-kraxel@redhat.com

ui/egl-helpers.c

@@ -83,7 +83,7 @@ void egl_fb_setup_new_tex(egl_fb *fb, int width, int height)
 
     glGenTextures(1, &texture);
     glBindTexture(GL_TEXTURE_2D, texture);
-    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height,
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height,
                  0, GL_BGRA, GL_UNSIGNED_BYTE, 0);
 
     egl_fb_setup_for_tex(fb, width, height, texture, true);