[gtk+] Revise the coordinate handling one more time

[Matthias Clasen <matthiasc src gnome org>]

commit 5280a2c8740f003a1321e4d0f3af79dcf3d4e09d
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Oct 8 18:36:57 2017 -0400

    Revise the coordinate handling one more time
    
    This makes the new reftests pass and hopefully does not
    break other things.

 gsk/gskvulkanrenderpass.c |   14 ++++++++++++--
 1 files changed, 12 insertions(+), 2 deletions(-)
---
diff --git a/gsk/gskvulkanrenderpass.c b/gsk/gskvulkanrenderpass.c
index a216fae..a47d3bb 100644
--- a/gsk/gskvulkanrenderpass.c
+++ b/gsk/gskvulkanrenderpass.c
@@ -1009,21 +1009,31 @@ gsk_vulkan_render_pass_upload (GskVulkanRenderPass  *self,
           {
             GskRenderNode *start = gsk_cross_fade_node_get_start_child (op->render.node);
             GskRenderNode *end = gsk_cross_fade_node_get_end_child (op->render.node);
+            const graphene_rect_t *bounds = &op->render.node->bounds;
 
             op->render.source = gsk_vulkan_render_pass_get_node_as_texture (self,
                                                                             render,
                                                                             uploader,
                                                                             start,
-                                                                            &op->render.node->bounds,
+                                                                            &start->bounds,
                                                                             clip,
                                                                             &op->render.source_rect);
+            op->render.source_rect.origin.x = (bounds->origin.x - 
start->bounds.origin.x)/start->bounds.size.width;
+            op->render.source_rect.origin.y = (bounds->origin.y - 
start->bounds.origin.y)/start->bounds.size.height;
+            op->render.source_rect.size.width = bounds->size.width / start->bounds.size.width;
+            op->render.source_rect.size.height = bounds->size.height / start->bounds.size.height;
+
             op->render.source2 = gsk_vulkan_render_pass_get_node_as_texture (self,
                                                                              render,
                                                                              uploader,
                                                                              end,
-                                                                             &op->render.node->bounds,
+                                                                             &end->bounds,
                                                                              clip,
                                                                              &op->render.source2_rect);
+            op->render.source2_rect.origin.x = (bounds->origin.x - 
end->bounds.origin.x)/end->bounds.size.width;
+            op->render.source2_rect.origin.y = (bounds->origin.y - 
end->bounds.origin.y)/end->bounds.size.height;
+            op->render.source2_rect.size.width = bounds->size.width / end->bounds.size.width;
+            op->render.source2_rect.size.height = bounds->size.height / end->bounds.size.height;
           }
           break;