linux: add an option to disable FBO support for platforms that don't have it.

Review URL: http://codereview.chromium.org/551218

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@37737 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 21 insertions, 3 deletions

diff --git a/o3d/core/core.gyp b/o3d/core/core.gyp
index f324884..218a010 100644
--- a/o3d/core/core.gyp
+++ b/o3d/core/core.gyp
@@ -60,6 +60,11 @@
           ],
         },
       ],
+      ['disable_fbo == 1', {
+        'defines': [
+          'DISABLE_FBO',
+        ],
+      }],
     ],
   },
   'includes': [
diff --git a/o3d/core/cross/gles2/render_surface_gles2.cc b/o3d/core/cross/gles2/render_surface_gles2.cc
index 5263828..ee0aff9 100644
--- a/o3d/core/cross/gles2/render_surface_gles2.cc
+++ b/o3d/core/cross/gles2/render_surface_gles2.cc
@@ -85,6 +85,7 @@ RenderDepthStencilSurfaceGLES2::RenderDepthStencilSurfaceGLES2(
     int height)
     : RenderDepthStencilSurface(service_locator, width, height) {
 
+#ifndef DISABLE_FBO
   // If packed depth stencil is supported, create only one buffer for both
   // depth and stencil.
   if (GLEW_EXT_packed_depth_stencil) {
@@ -112,15 +113,17 @@ RenderDepthStencilSurfaceGLES2::RenderDepthStencilSurfaceGLES2(
                              height);
     CHECK_GL_ERROR();
   }
+#endif
 }
 
 RenderDepthStencilSurfaceGLES2::~RenderDepthStencilSurfaceGLES2() {
+#ifndef DISABLE_FBO
   if (GLEW_EXT_packed_depth_stencil) {
     glDeleteRenderbuffersEXT(1, render_buffers_);
   } else {
     glDeleteRenderbuffersEXT(2, render_buffers_);
   }
+#endif
 }
 
 }  // end namespace o3d
-
diff --git a/o3d/core/cross/gles2/renderer_gles2.cc b/o3d/core/cross/gles2/renderer_gles2.cc
index 6d012e2..7a0d3b7 100644
--- a/o3d/core/cross/gles2/renderer_gles2.cc
+++ b/o3d/core/cross/gles2/renderer_gles2.cc
@@ -33,7 +33,6 @@
 // This file contains the definition of the RendererGLES2 class that
 // implements the abstract Renderer API using OpenGLES2.
 
-
 #include "core/cross/gles2/renderer_gles2.h"
 
 #include "core/cross/error.h"
@@ -168,6 +167,7 @@ GLenum ConvertStencilOp(State::StencilOperation stencil_func) {
   return GL_KEEP;
 }
 
+#ifndef DISABLE_FBO
 // Helper routine that will bind the surfaces stored in the RenderSurface and
 // RenderDepthStencilSurface arguments to the current OpenGLES2 context.
 // Returns true upon success.
@@ -241,6 +241,7 @@ bool InstallFramebufferObjects(const RenderSurface* surface,
   CHECK_GL_ERROR();
   return true;
 }
+#endif
 
 // Helper routine that returns a pointer to the non-NULL entry in the renderer's
 // stack of bound surfaces.
@@ -687,10 +688,12 @@ Renderer::InitStatus RendererGLES2::InitCommonGLES2() {
     return GPU_NOT_UP_TO_SPEC;
   }
 
+#ifndef DISABLE_FBO
   if (!GLEW_EXT_framebuffer_object) {
     DLOG(ERROR) << "GLES2 drivers do not support framebuffer objects.";
     return GPU_NOT_UP_TO_SPEC;
   }
+#endif
 
   SetSupportsNPOT(GLEW_ARB_texture_non_power_of_two != 0);
 
@@ -732,8 +735,10 @@ Renderer::InitStatus RendererGLES2::InitCommonGLES2() {
   SetClientSize(viewport[2], viewport[3]);
   CHECK_GL_ERROR();
 
+#ifndef DISABLE_FBO
   ::glGenFramebuffersEXT(1, &render_surface_framebuffer_);
   CHECK_GL_ERROR();
+#endif
 
   return SUCCESS;
 }
@@ -741,9 +746,11 @@ Renderer::InitStatus RendererGLES2::InitCommonGLES2() {
 // platform neutral destruction code
 void RendererGLES2::DestroyCommonGLES2() {
   MakeCurrentLazy();
+#ifndef DISABLE_FBO
   if (render_surface_framebuffer_) {
     ::glDeleteFramebuffersEXT(1, &render_surface_framebuffer_);
   }
+#endif
 }
 
 #ifdef OS_WIN
@@ -1283,12 +1290,14 @@ void RendererGLES2::SetRenderSurfacesPlatformSpecific(
   // of framebuffer objects with different attachment characterists and
   // switch between them here.
   MakeCurrentLazy();
+#ifndef DISABLE_FBO
   ::glBindFramebufferEXT(GL_FRAMEBUFFER, render_surface_framebuffer_);
   if (!InstallFramebufferObjects(surface, surface_depth)) {
     O3D_ERROR(service_locator())
         << "Failed to bind OpenGLES2 render target objects:"
         << surface->name() <<", "<< surface_depth->name();
   }
+#endif
   // RenderSurface rendering is performed with an inverted Y, so the front
   // face winding must be changed to clock-wise.  See comments for
   // UpdateHelperConstant.
@@ -1297,8 +1306,10 @@ void RendererGLES2::SetRenderSurfacesPlatformSpecific(
 
 void RendererGLES2::SetBackBufferPlatformSpecific() {
   MakeCurrentLazy();
+#ifndef DISABLE_FBO
   // Bind the default context, and restore the default front-face winding.
   ::glBindFramebufferEXT(GL_FRAMEBUFFER, 0);
+#endif
   glFrontFace(GL_CCW);
 }
 
@@ -1529,4 +1540,3 @@ Renderer* Renderer::CreateDefaultRenderer(ServiceLocator* service_locator) {
 }
 
 }  // namespace o3d
-