[cairo] [PATCH] gl/msaa: Share the depth/stencil buffer among all surfaces
Martin Robinson
mrobinson at igalia.com
Sat Dec 8 04:32:55 PST 2012
>From a7d684e6fe4bbeea2262276aaa57bb2a47c401df Mon Sep 17 00:00:00 2001
From: Martin Robinson <mrobinson at igalia.com>
Date: Mon, 5 Mar 2012 23:11:19 -0800
Subject: [PATCH] gl/msaa: Share the depth/stencil buffer among all surfaces
Instead of allocating a depth/stencil buffer for all surfaces, share a
common buffer that's the size of the largest surface. This reduces
video memory usage when there are many GL surfaces.
---
src/cairo-gl-device.c | 118 ++++++++++++++++++++++++++++++++++--------------
src/cairo-gl-private.h | 13 ++++++
src/cairo-gl-surface.c | 31 +++++++++++--
3 files changed, 124 insertions(+), 38 deletions(-)
diff --git a/src/cairo-gl-device.c b/src/cairo-gl-device.c
index 37c837d..b6a9c15 100644
--- a/src/cairo-gl-device.c
+++ b/src/cairo-gl-device.c
@@ -112,6 +112,11 @@ _gl_finish (void *device)
for (n = 0; n < ARRAY_LENGTH (ctx->glyph_cache); n++)
_cairo_gl_glyph_cache_fini (ctx, &ctx->glyph_cache[n]);
+ if (ctx->depth_stencil_info.id)
+ ctx->dispatch.DeleteRenderbuffers (1, &ctx->depth_stencil_info.id);
+ if (ctx->msaa_depth_stencil_info.id)
+ ctx->dispatch.DeleteRenderbuffers (1, &ctx->msaa_depth_stencil_info.id);
+
_gl_unlock (device);
}
@@ -453,36 +458,59 @@ _cairo_gl_ensure_multisampling (cairo_gl_context_t *ctx,
}
#endif
+static void
+_cairo_gl_replace_msaa_depth_stencil_buffer (cairo_gl_context_t *ctx,
+ int width,
+ int height)
+{
+ cairo_gl_dispatch_t *dispatch = &ctx->dispatch;
+
+ if (ctx->msaa_depth_stencil_info.id)
+ dispatch->DeleteRenderbuffers (1, &ctx->msaa_depth_stencil_info.id);
+
+ dispatch->GenRenderbuffers (1, &ctx->msaa_depth_stencil_info.id);
+ dispatch->BindRenderbuffer (GL_RENDERBUFFER, ctx->msaa_depth_stencil_info.id);
+ dispatch->RenderbufferStorageMultisample (GL_RENDERBUFFER, ctx->num_samples,
+ _get_depth_stencil_format (ctx),
+ width, height);
+ ctx->msaa_depth_stencil_info.width = width;
+ ctx->msaa_depth_stencil_info.height = height;
+ ctx->msaa_depth_stencil_info.surfaces_with_same_size = 0;
+}
+
static cairo_bool_t
_cairo_gl_ensure_msaa_depth_stencil_buffer (cairo_gl_context_t *ctx,
cairo_gl_surface_t *surface)
{
cairo_gl_dispatch_t *dispatch = &ctx->dispatch;
- if (surface->msaa_depth_stencil)
- return TRUE;
-
_cairo_gl_ensure_framebuffer (ctx, surface);
#if CAIRO_HAS_GL_SURFACE
if (ctx->gl_flavor == CAIRO_GL_FLAVOR_DESKTOP)
_cairo_gl_ensure_multisampling (ctx, surface);
#endif
- dispatch->GenRenderbuffers (1, &surface->msaa_depth_stencil);
- dispatch->BindRenderbuffer (GL_RENDERBUFFER,
- surface->msaa_depth_stencil);
+ if (! ctx->msaa_depth_stencil_info.id ||
+ ctx->msaa_depth_stencil_info.width < surface->width ||
+ ctx->msaa_depth_stencil_info.height < surface->height) {
+ _cairo_gl_replace_msaa_depth_stencil_buffer (ctx,
+ surface->width,
+ surface->height);
+ }
- dispatch->RenderbufferStorageMultisample (GL_RENDERBUFFER,
- ctx->num_samples,
- _get_depth_stencil_format (ctx),
- surface->width,
- surface->height);
+ assert (ctx->msaa_depth_stencil_info.id);
+ if (surface->msaa_depth_stencil == ctx->msaa_depth_stencil_info.id)
+ return TRUE;
+
+ if (ctx->msaa_depth_stencil_info.width == surface->width &&
+ ctx->msaa_depth_stencil_info.height == surface->height)
+ ctx->msaa_depth_stencil_info.surfaces_with_same_size++;
#if CAIRO_HAS_GL_SURFACE
if (ctx->gl_flavor == CAIRO_GL_FLAVOR_DESKTOP) {
dispatch->FramebufferRenderbuffer (GL_FRAMEBUFFER,
GL_DEPTH_STENCIL_ATTACHMENT,
GL_RENDERBUFFER,
- surface->msaa_depth_stencil);
+ ctx->msaa_depth_stencil_info.id);
}
#endif
@@ -491,50 +519,72 @@ _cairo_gl_ensure_msaa_depth_stencil_buffer (cairo_gl_context_t *ctx,
dispatch->FramebufferRenderbuffer (GL_FRAMEBUFFER,
GL_DEPTH_ATTACHMENT,
GL_RENDERBUFFER,
- surface->msaa_depth_stencil);
+ ctx->msaa_depth_stencil_info.id);
dispatch->FramebufferRenderbuffer (GL_FRAMEBUFFER,
GL_STENCIL_ATTACHMENT,
GL_RENDERBUFFER,
- surface->msaa_depth_stencil);
+ ctx->msaa_depth_stencil_info.id);
}
#endif
- if (dispatch->CheckFramebufferStatus (GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
- dispatch->DeleteRenderbuffers (1, &surface->msaa_depth_stencil);
- surface->msaa_depth_stencil = 0;
- return FALSE;
- }
+ surface->msaa_depth_stencil = ctx->msaa_depth_stencil_info.id;
+ if (dispatch->CheckFramebufferStatus (GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+ return FALSE;
return TRUE;
}
+static void
+_cairo_gl_replace_depth_stencil_buffer (cairo_gl_context_t *ctx,
+ int width,
+ int height)
+{
+ cairo_gl_dispatch_t *dispatch = &ctx->dispatch;
+
+ if (ctx->depth_stencil_info.id)
+ dispatch->DeleteRenderbuffers (1, &ctx->depth_stencil_info.id);
+
+ dispatch->GenRenderbuffers (1, &ctx->depth_stencil_info.id);
+ dispatch->BindRenderbuffer (GL_RENDERBUFFER, ctx->depth_stencil_info.id);
+ dispatch->RenderbufferStorage (GL_RENDERBUFFER,
+ _get_depth_stencil_format (ctx),
+ width, height);
+ ctx->depth_stencil_info.width = width;
+ ctx->depth_stencil_info.height = height;
+ ctx->depth_stencil_info.surfaces_with_same_size = 0;
+}
+
static cairo_bool_t
_cairo_gl_ensure_depth_stencil_buffer (cairo_gl_context_t *ctx,
cairo_gl_surface_t *surface)
{
cairo_gl_dispatch_t *dispatch = &ctx->dispatch;
- if (surface->depth_stencil)
- return TRUE;
-
_cairo_gl_ensure_framebuffer (ctx, surface);
- dispatch->GenRenderbuffers (1, &surface->depth_stencil);
- dispatch->BindRenderbuffer (GL_RENDERBUFFER, surface->depth_stencil);
- dispatch->RenderbufferStorage (GL_RENDERBUFFER,
- _get_depth_stencil_format (ctx),
- surface->width, surface->height);
+ if (! ctx->depth_stencil_info.id ||
+ ctx->depth_stencil_info.width < surface->width ||
+ ctx->depth_stencil_info.height < surface->height) {
+ _cairo_gl_replace_depth_stencil_buffer (ctx,
+ surface->width,
+ surface->height);
+ }
+
+ if (surface->depth_stencil == ctx->depth_stencil_info.id)
+ return TRUE;
+
+ if (ctx->depth_stencil_info.width == surface->width &&
+ ctx->depth_stencil_info.height == surface->height)
+ ctx->depth_stencil_info.surfaces_with_same_size++;
dispatch->FramebufferRenderbuffer (GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT,
- GL_RENDERBUFFER, surface->depth_stencil);
+ GL_RENDERBUFFER, ctx->depth_stencil_info.id);
dispatch->FramebufferRenderbuffer (GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT,
- GL_RENDERBUFFER, surface->depth_stencil);
- if (dispatch->CheckFramebufferStatus (GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
- dispatch->DeleteRenderbuffers (1, &surface->depth_stencil);
- surface->depth_stencil = 0;
- return FALSE;
- }
+ GL_RENDERBUFFER, ctx->depth_stencil_info.id);
+ surface->depth_stencil = ctx->depth_stencil_info.id;
+ if (dispatch->CheckFramebufferStatus (GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+ return FALSE;
return TRUE;
}
diff --git a/src/cairo-gl-private.h b/src/cairo-gl-private.h
index 7c97c49..088a874 100644
--- a/src/cairo-gl-private.h
+++ b/src/cairo-gl-private.h
@@ -301,6 +301,13 @@ typedef struct _cairo_gl_dispatch {
GLint level, GLsizei samples);
} cairo_gl_dispatch_t;
+typedef struct _cairo_gl_shared_depth_stencil_info {
+ GLuint id;
+ int width;
+ int height;
+ unsigned surfaces_with_same_size;
+} cairo_gl_shared_depth_stencil_info_t;
+
struct _cairo_gl_context {
cairo_device_t base;
@@ -353,6 +360,12 @@ struct _cairo_gl_context {
cairo_bool_t thread_aware;
+ /* GL stencil and depth buffers are shared among all surfaces
+ to preserve memory. In the future this could be a pool of renderbuffers
+ with an eviction policy. */
+ cairo_gl_shared_depth_stencil_info_t depth_stencil_info;
+ cairo_gl_shared_depth_stencil_info_t msaa_depth_stencil_info;
+
void (*acquire) (void *ctx);
void (*release) (void *ctx);
diff --git a/src/cairo-gl-surface.c b/src/cairo-gl-surface.c
index c0ee79f..7c93322 100644
--- a/src/cairo-gl-surface.c
+++ b/src/cairo-gl-surface.c
@@ -946,6 +946,23 @@ static int _cairo_gl_surface_flavor (cairo_gl_surface_t *surface)
return ctx->gl_flavor;
}
+static void
+_cairo_gl_shrink_shared_renderbuffer (cairo_gl_context_t *ctx,
+ cairo_gl_shared_depth_stencil_info_t *info,
+ int surface_width,
+ int surface_height)
+{
+ if (info->width != surface_width || info->height != surface_height)
+ return;
+
+ /* Force the creation of a new shared renderbuffer if we are the
+ * last surface that has the same size as our old shared buffer. */
+ ctx->dispatch.DeleteRenderbuffers (1, &info->id);
+ info->height = 0;
+ info->width = 0;
+ info->id = 0;
+}
+
static cairo_status_t
_cairo_gl_surface_finish (void *abstract_surface)
{
@@ -968,18 +985,24 @@ _cairo_gl_surface_finish (void *abstract_surface)
if (surface->fb)
ctx->dispatch.DeleteFramebuffers (1, &surface->fb);
- if (surface->depth_stencil)
- ctx->dispatch.DeleteRenderbuffers (1, &surface->depth_stencil);
if (surface->owns_tex)
glDeleteTextures (1, &surface->tex);
+ if (surface->depth_stencil) {
+ _cairo_gl_shrink_shared_renderbuffer (ctx, &ctx->depth_stencil_info,
+ surface->width, surface->height);
+ }
+
#if CAIRO_HAS_GL_SURFACE
- if (surface->msaa_depth_stencil)
- ctx->dispatch.DeleteRenderbuffers (1, &surface->msaa_depth_stencil);
if (surface->msaa_fb)
ctx->dispatch.DeleteFramebuffers (1, &surface->msaa_fb);
if (surface->msaa_rb)
ctx->dispatch.DeleteRenderbuffers (1, &surface->msaa_rb);
+
+ if (surface->msaa_depth_stencil) {
+ _cairo_gl_shrink_shared_renderbuffer (ctx, &ctx->msaa_depth_stencil_info,
+ surface->width, surface->height);
+ }
#endif
return _cairo_gl_context_release (ctx, status);
--
1.7.10.4
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