gl: do not force flush everytime uploading a glyph image to glyph cache

In normal cases, we want to flush pending operations reading from the
texture before modifying its contents.  However during uploading of
glyphs into the glyph cache, we repeatedly modify the texture as we
construct the vbo (whilst referencing it for that operation). We track
unused areas in the glyph cache so that if we run out of space, we can
explicitly flush the pending glyphs and start afresh and avoid having to
flush the operation in common case.

6 files changed, 24 insertions, 15 deletions

diff --git a/src/cairo-gl-glyphs.c b/src/cairo-gl-glyphs.c
index 3f65248d..34b5d72f 100644
--- a/src/cairo-gl-glyphs.c
+++ b/src/cairo-gl-glyphs.c
@@ -134,7 +134,7 @@ _cairo_gl_glyph_cache_add_glyph (cairo_gl_context_t *ctx,
     status = _cairo_gl_surface_draw_image (cache->surface, glyph_surface,
                                            0, 0,
                                            glyph_surface->width, glyph_surface->height,
-                                           node->x, node->y);
+                                           node->x, node->y, FALSE);
     if (unlikely (status))
 	return status;
 
diff --git a/src/cairo-gl-private.h b/src/cairo-gl-private.h
index 2b254f98..cc17c709 100644
--- a/src/cairo-gl-private.h
+++ b/src/cairo-gl-private.h
@@ -437,7 +437,8 @@ _cairo_gl_surface_draw_image (cairo_gl_surface_t *dst,
 			      cairo_image_surface_t *src,
 			      int src_x, int src_y,
 			      int width, int height,
-			      int dst_x, int dst_y);
+			      int dst_x, int dst_y,
+			      cairo_bool_t force_flush);
 
 static cairo_always_inline cairo_bool_t
 _cairo_gl_device_has_glsl (cairo_device_t *device)
diff --git a/src/cairo-gl-spans-compositor.c b/src/cairo-gl-spans-compositor.c
index 92e57797..c5d97aa7 100644
--- a/src/cairo-gl-spans-compositor.c
+++ b/src/cairo-gl-spans-compositor.c
@@ -311,7 +311,7 @@ draw_image_boxes (void *_dst,
 	    status = _cairo_gl_surface_draw_image (dst, image,
 						   x + dx, y + dy,
 						   w, h,
-						   x, y);
+						   x, y, TRUE);
 	    if (unlikely (status))
 		return status;
 	}
diff --git a/src/cairo-gl-surface-legacy.c b/src/cairo-gl-surface-legacy.c
index 61bdd1fa..92b27c90 100644
--- a/src/cairo-gl-surface-legacy.c
+++ b/src/cairo-gl-surface-legacy.c
@@ -77,7 +77,8 @@ _cairo_gl_surface_release_dest_image (void		      *abstract_surface,
     status = _cairo_gl_surface_draw_image (abstract_surface, image,
 					   0, 0,
 					   image->width, image->height,
-					   image_rect->x, image_rect->y);
+					   image_rect->x, image_rect->y,
+					   TRUE);
     /* as we created the image, its format should be directly applicable */
     assert (status == CAIRO_STATUS_SUCCESS);
 
@@ -126,7 +127,7 @@ _cairo_gl_surface_clone_similar (void		     *abstract_surface,
 	status = _cairo_gl_surface_draw_image (clone, image_src,
 					       src_x, src_y,
 					       width, height,
-					       0, 0);
+					       0, 0, TRUE);
 	if (status) {
 	    cairo_surface_destroy (&clone->base);
 	    return status;
@@ -236,7 +237,7 @@ _cairo_gl_surface_composite (cairo_operator_t		  op,
             status = _cairo_gl_surface_draw_image (dst, image,
                                                    dx, dy,
                                                    width, height,
-                                                   dst_x, dst_y);
+                                                   dst_x, dst_y, TRUE);
             if (status != CAIRO_INT_STATUS_UNSUPPORTED)
                 return status;
         }
diff --git a/src/cairo-gl-surface.c b/src/cairo-gl-surface.c
index 922f2343..1d7515a4 100644
--- a/src/cairo-gl-surface.c
+++ b/src/cairo-gl-surface.c
@@ -840,7 +840,8 @@ _cairo_gl_surface_draw_image (cairo_gl_surface_t *dst,
 			      cairo_image_surface_t *src,
 			      int src_x, int src_y,
 			      int width, int height,
-			      int dst_x, int dst_y)
+			      int dst_x, int dst_y,
+			      cairo_bool_t force_flush)
 {
     GLenum internal_format, format, type;
     cairo_bool_t has_alpha, needs_swap;
@@ -882,9 +883,11 @@ _cairo_gl_surface_draw_image (cairo_gl_surface_t *dst,
 
     cpp = PIXMAN_FORMAT_BPP (src->pixman_format) / 8;
 
-    status = _cairo_gl_surface_flush (&dst->base, 0);
-    if (unlikely (status))
-	goto FAIL;
+    if (force_flush) {
+	status = _cairo_gl_surface_flush (&dst->base, 0);
+	if (unlikely (status))
+	    goto FAIL;
+    }
 
     if (_cairo_gl_surface_is_texture (dst)) {
 	void *data_start = src->data + src_y * src->stride + src_x * cpp;
@@ -951,7 +954,7 @@ _cairo_gl_surface_draw_image (cairo_gl_surface_t *dst,
                                                src,
                                                src_x, src_y,
                                                width, height,
-                                               0, 0);
+                                               0, 0, force_flush);
         if (status == CAIRO_INT_STATUS_SUCCESS) {
             cairo_surface_pattern_t tmp_pattern;
 	    cairo_rectangle_int_t r;
@@ -1231,7 +1234,8 @@ _cairo_gl_surface_unmap_image (void		      *abstract_surface,
 					   0, 0,
 					   image->width, image->height,
 					   image->base.device_transform_inverse.x0,
-					   image->base.device_transform_inverse.y0);
+					   image->base.device_transform_inverse.y0,
+					   TRUE);
 
     cairo_surface_finish (&image->base);
     cairo_surface_destroy (&image->base);
diff --git a/src/cairo-gl-traps-compositor.c b/src/cairo-gl-traps-compositor.c
index 9589ffcb..548162be 100644
--- a/src/cairo-gl-traps-compositor.c
+++ b/src/cairo-gl-traps-compositor.c
@@ -96,7 +96,8 @@ draw_image_boxes (void *_dst,
 	    status = _cairo_gl_surface_draw_image (dst, image,
 						   x + dx, y + dy,
 						   w, h,
-						   x, y);
+						   x, y,
+						   TRUE);
 	    if (unlikely (status))
 		return status;
 	}
@@ -345,7 +346,8 @@ traps_to_operand (void *_dst,
 					   (cairo_image_surface_t *)image,
 					   0, 0,
 					   extents->width, extents->height,
-					   0, 0);
+					   0, 0,
+					   TRUE);
     cairo_surface_destroy (image);
 
     if (unlikely (status))
@@ -456,7 +458,8 @@ tristrip_to_surface (void *_dst,
 					   (cairo_image_surface_t *)image,
 					   0, 0,
 					   extents->width, extents->height,
-					   0, 0);
+					   0, 0,
+					   TRUE);
     cairo_surface_destroy (image);
     if (unlikely (status)) {
 	cairo_surface_destroy (mask);