[gtk+] vulkan: Fix coordinate setup

[Benjamin Otte <otte src gnome org>]

commit 3a79b173090c8777498e4cd4e1e7049571ed5375
Author: Benjamin Otte <otte redhat com>
Date:   Mon Dec 26 14:49:34 2016 +0100

    vulkan: Fix coordinate setup
    
    This makes rendering textures work when the top left of the rendered
    texture is not at (0, 0).

 gsk/gskvulkanrender.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)
---
diff --git a/gsk/gskvulkanrender.c b/gsk/gskvulkanrender.c
index 6f57c1d..59c5924 100644
--- a/gsk/gskvulkanrender.c
+++ b/gsk/gskvulkanrender.c
@@ -57,8 +57,8 @@ gsk_vulkan_render_compute_mvp (GskVulkanRender       *self,
 
   if (rect)
     {
-      self->scissor = (VkRect2D) { { rect->origin.x, rect->origin.y }, { rect->size.width, rect->size.height 
} };
-      self->viewport = self->scissor;
+      self->scissor = (VkRect2D) { { 0, 0 }, { rect->size.width, rect->size.height } };
+      self->viewport = (VkRect2D) { { rect->origin.x, rect->origin.y }, { rect->size.width, 
rect->size.height } };
       self->scale_factor = 1;
     }
   else
@@ -78,8 +78,8 @@ gsk_vulkan_render_compute_mvp (GskVulkanRender       *self,
 
   graphene_matrix_init_scale (&modelview, self->scale_factor, self->scale_factor, 1.0);
   graphene_matrix_init_ortho (&projection,
-                              self->viewport.offset.x, self->viewport.extent.width,
-                              self->viewport.offset.y, self->viewport.extent.height,
+                              self->viewport.offset.x, self->viewport.offset.x + self->viewport.extent.width,
+                              self->viewport.offset.y, self->viewport.offset.y + 
self->viewport.extent.height,
                               ORTHO_NEAR_PLANE,
                               ORTHO_FAR_PLANE);
 
@@ -471,8 +471,8 @@ gsk_vulkan_render_draw (GskVulkanRender   *self,
                     0,
                     1,
                     &(VkViewport) {
-                      .x = self->viewport.offset.x,
-                      .y = self->viewport.offset.x,
+                      .x = 0,
+                      .y = 0,
                       .width = self->viewport.extent.width,
                       .height = self->viewport.extent.height,
                       .minDepth = 0,