gpu: Add support for GLX_EXT_texture_from_pixmap extension.

ui/gl/gl_surface_glx.cc

Index: ui/gl/gl_surface_glx.cc
diff --git a/ui/gl/gl_surface_glx.cc b/ui/gl/gl_surface_glx.cc
index a5609cd8e23cf35e0b20a3506d0150e3c9bf53ee..5cc4fe1313db6af5c070808354a1a987d1e1e93f 100644
--- a/ui/gl/gl_surface_glx.cc
+++ b/ui/gl/gl_surface_glx.cc
@@ -321,4 +321,150 @@ PbufferGLSurfaceGLX::~PbufferGLSurfaceGLX() {
   Destroy();
 }
 
+PixmapGLSurfaceGLX::PixmapGLSurfaceGLX(XID pixmap)
+  : config_(NULL),
+    pixmap_(pixmap),
+    glx_pixmap_(0) {
+}
+
+bool PixmapGLSurfaceGLX::Initialize() {
+  DCHECK(pixmap_);
+
+  XID root;
+  int x, y;
+  unsigned int width, height, border_width, depth;
+  if (!XGetGeometry(g_display, pixmap_, &root, &x, &y, &width, &height,
+                    &border_width, &depth)) {
+    LOG(ERROR) << "XGetGeometry failed for pixmap " << pixmap_ << ".";
+    return false;
+  }
+  size_ = gfx::Size(width, height);
+
+  int num_elements = 0;
+  scoped_ptr_malloc<GLXFBConfig, ScopedPtrXFree> configs(
+      glXGetFBConfigs(g_display,
+                      DefaultScreen(g_display),
+                      &num_elements));
+  if (!configs.get()) {
+    LOG(ERROR) << "glXGetFBConfigs failed.";
+    return false;
+  }
+  if (!num_elements) {
+    LOG(ERROR) << "glXGetFBConfigs returned 0 elements.";
+    return false;
+  }
+  bool found = false;
+  int i;
+  for (i = 0; i < num_elements; ++i) {
+    int value;
+    if (glXGetFBConfigAttrib(
+            g_display, configs.get()[i], GLX_DRAWABLE_TYPE, &value)) {
+      LOG(ERROR) << "glXGetFBConfigAttrib failed.";
+      return false;
+    }
+    if (!(value & GLX_PIXMAP_BIT))
+      continue;
+    if (glXGetFBConfigAttrib(
+            g_display, configs.get()[i], GLX_BIND_TO_TEXTURE_TARGETS_EXT,
+            &value)) {
+      LOG(ERROR) << "glXGetFBConfigAttrib failed.";
+      return false;
+    }
+    if (!(value & GLX_TEXTURE_2D_BIT_EXT))
+      continue;
+    if (glXGetFBConfigAttrib(
+            g_display, configs.get()[i], (depth == 32) ?
+            GLX_BIND_TO_TEXTURE_RGBA_EXT : GLX_BIND_TO_TEXTURE_RGB_EXT,
+            &value)) {
+      LOG(ERROR) << "glXGetFBConfigAttrib failed.";
+      return false;
+    }
+    if (value == GL_FALSE)
+      continue;
+    if (glXGetFBConfigAttrib(
+            g_display, configs.get()[i], GLX_DOUBLEBUFFER, &value)) {
+      LOG(ERROR) << "glXGetFBConfigAttrib failed.";
+      return false;
+    }
+    // Avoid double buffered config.
+    if (value == GL_TRUE)
+      continue;
+    if (glXGetFBConfigAttrib(
+            g_display, configs.get()[i], GLX_BUFFER_SIZE, &value)) {
+      LOG(ERROR) << "glXGetFBConfigAttrib failed.";
+      return false;
+    }
+    if (value < static_cast<int>(depth))
+      continue;
+
+    found = true;
+    break;
+  }
+
+  if (!found) {
+    LOG(ERROR) << "Failed to find valid FBConfig for pixmap.";
+    return false;
+  }
+
+  config_ = configs.get()[i];
+
+  std::vector<int> attribs;
+  attribs.push_back(GLX_TEXTURE_TARGET_EXT);
+  attribs.push_back(GLX_TEXTURE_2D_EXT);
+  attribs.push_back(GLX_TEXTURE_FORMAT_EXT);
+  if (depth == 32)
+    attribs.push_back(GLX_TEXTURE_FORMAT_RGBA_EXT);
+  else
+    attribs.push_back(GLX_TEXTURE_FORMAT_RGB_EXT);
+  attribs.push_back(0);
+
+  glx_pixmap_ = glXCreatePixmap(
+      g_display, static_cast<GLXFBConfig>(config_), pixmap_, &attribs.front());
+  if (!glx_pixmap_) {
+    Destroy();
+    LOG(ERROR) << "glXCreatePixmap failed.";
+    return false;
+  }
+
+  return true;
+}
+
+void PixmapGLSurfaceGLX::Destroy() {
+  if (glx_pixmap_) {
+    glXDestroyGLXPixmap(g_display, glx_pixmap_);
+    glx_pixmap_ = 0;
+  }
+
+  config_ = NULL;
+}
+
+bool PixmapGLSurfaceGLX::IsOffscreen() {
+  return true;
+}
+
+bool PixmapGLSurfaceGLX::SwapBuffers() {
+  NOTREACHED() << "Attempted to call SwapBuffers on a pixmap.";
+  return false;
+}
+
+gfx::Size PixmapGLSurfaceGLX::GetSize() {
+  return size_;
+}
+
+void* PixmapGLSurfaceGLX::GetHandle() {
+  return reinterpret_cast<void*>(glx_pixmap_);
+}
+
+void* PixmapGLSurfaceGLX::GetShareHandle() {
+  return reinterpret_cast<void*>(pixmap_);
+}
+
+void* PixmapGLSurfaceGLX::GetConfig() {
+  return config_;
+}
+
+PixmapGLSurfaceGLX::~PixmapGLSurfaceGLX() {
+  Destroy();
+}
+
 }  // namespace gfx