From 652c8c31cfdd98ef38803b88325d76aee187ea5e Mon Sep 17 00:00:00 2001
From: Robert Bragg <robert@linux.intel.com>
Date: Sun, 20 Nov 2011 18:50:29 +0000
Subject: [PATCH] avoid touching fb matrix stack directly

This ensures we don't touch a framebuffer's matrix stack directly if we
are also relying on _cogl_framebuffer_flush_state(). We want to get to
the point where we can set dirty flags against framebuffer state at the
point it changes but that means we can't allow direct access to the
matrix stack. _cogl_texture_draw_and_read() has now been changed so it
uses cogl_framebuffer_ methods to update the matrix stacks including
adding new internal _cogl_framebuffer_push/pop_projection() functions
that allow us to set transient projections.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
---
 cogl/cogl-framebuffer-private.h |  6 ++++++
 cogl/cogl-framebuffer.c         | 21 +++++++++++++++++++++
 cogl/cogl-texture.c             | 24 +++++++++---------------
 3 files changed, 36 insertions(+), 15 deletions(-)

diff --git a/cogl/cogl-framebuffer-private.h b/cogl/cogl-framebuffer-private.h
index e168b6e0c..6499c80a8 100644
--- a/cogl/cogl-framebuffer-private.h
+++ b/cogl/cogl-framebuffer-private.h
@@ -334,4 +334,10 @@ _cogl_blit_framebuffer (unsigned int src_x,
                         unsigned int width,
                         unsigned int height);
 
+void
+_cogl_framebuffer_push_projection (CoglFramebuffer *framebuffer);
+
+void
+_cogl_framebuffer_pop_projection (CoglFramebuffer *framebuffer);
+
 #endif /* __COGL_FRAMEBUFFER_PRIVATE_H */
diff --git a/cogl/cogl-framebuffer.c b/cogl/cogl-framebuffer.c
index f5cc87786..c372963c4 100644
--- a/cogl/cogl-framebuffer.c
+++ b/cogl/cogl-framebuffer.c
@@ -1915,6 +1915,27 @@ cogl_framebuffer_orthographic (CoglFramebuffer *framebuffer,
   _cogl_matrix_stack_set (projection_stack, &ortho);
 }
 
+void
+_cogl_framebuffer_push_projection (CoglFramebuffer *framebuffer)
+{
+  CoglMatrixStack *projection_stack =
+    _cogl_framebuffer_get_projection_stack (framebuffer);
+  _cogl_matrix_stack_push (projection_stack);
+
+  framebuffer->context->current_draw_buffer_changes |=
+    COGL_FRAMEBUFFER_STATE_PROJECTION;
+}
+
+void
+_cogl_framebuffer_pop_projection (CoglFramebuffer *framebuffer)
+{
+  CoglMatrixStack *projection_stack =
+    _cogl_framebuffer_get_projection_stack (framebuffer);
+  _cogl_matrix_stack_pop (projection_stack);
+  framebuffer->context->current_draw_buffer_changes |=
+    COGL_FRAMEBUFFER_STATE_PROJECTION;
+}
+
 void
 cogl_framebuffer_get_modelview_matrix (CoglFramebuffer *framebuffer,
                                        CoglMatrix *matrix)
diff --git a/cogl/cogl-texture.c b/cogl/cogl-texture.c
index 23fcf8c49..a072d911d 100644
--- a/cogl/cogl-texture.c
+++ b/cogl/cogl-texture.c
@@ -874,8 +874,6 @@ _cogl_texture_draw_and_read (CoglTexture *texture,
   CoglFramebuffer *framebuffer;
   float viewport[4];
   CoglBitmap *alpha_bmp;
-  CoglMatrixStack *projection_stack;
-  CoglMatrixStack *modelview_stack;
   int target_width = _cogl_bitmap_get_width (target_bmp);
   int target_height = _cogl_bitmap_get_height (target_bmp);
   int target_rowstride = _cogl_bitmap_get_rowstride (target_bmp);
@@ -896,18 +894,14 @@ _cogl_texture_draw_and_read (CoglTexture *texture,
    * works)
    */
 
-  projection_stack = _cogl_framebuffer_get_projection_stack (framebuffer);
-  _cogl_matrix_stack_push (projection_stack);
-  _cogl_matrix_stack_load_identity (projection_stack);
-  _cogl_matrix_stack_ortho (projection_stack,
-                            0, viewport[2],
-                            viewport[3], 0,
-                            0,
-                            100);
+  _cogl_framebuffer_push_projection (framebuffer);
+  cogl_framebuffer_orthographic (framebuffer,
+                                 0, 0,
+                                 viewport[2], viewport[3],
+                                 0, 100);
 
-  modelview_stack = _cogl_framebuffer_get_modelview_stack (framebuffer);
-  _cogl_matrix_stack_push (modelview_stack);
-  _cogl_matrix_stack_load_identity (modelview_stack);
+  cogl_framebuffer_push_matrix (framebuffer);
+  cogl_framebuffer_identity_matrix (framebuffer);
 
   /* Direct copy operation */
 
@@ -999,8 +993,8 @@ _cogl_texture_draw_and_read (CoglTexture *texture,
     }
 
   /* Restore old state */
-  _cogl_matrix_stack_pop (modelview_stack);
-  _cogl_matrix_stack_pop (projection_stack);
+  cogl_framebuffer_pop_matrix (framebuffer);
+  _cogl_framebuffer_pop_projection (framebuffer);
 
   /* restore the original pipeline */
   cogl_pop_source ();