More refactoring of offscreen rendering

1 files changed, 61 insertions, 0 deletions

diff --git a/tests/fboutils.cc b/tests/fboutils.cc
new file mode 100644
index 0000000..d0430df
--- /dev/null
+++ b/tests/fboutils.cc
@@ -0,0 +1,61 @@
+#include "fboutils.h"
+#include <iostream>
+
+GLuint fbo_create(GLsizei width, GLsizei height)
+{
+  // Test if framebuffer objects are supported
+  // FIXME: Use GLEW
+  const GLubyte* strExt = glGetString(GL_EXTENSIONS);
+  GLboolean fboSupported = gluCheckExtension((const GLubyte*)"GL_EXT_framebuffer_object", strExt);
+  if (!fboSupported) {
+		std::cerr << "Your system does not support framebuffer extension - unable to render scene\n";
+		return 0;
+	}
+
+  // Create an FBO
+  GLuint fbo = 0;
+  GLuint renderBuffer = 0;
+  GLuint depthBuffer = 0;
+  // Depth buffer to use for depth testing - optional if you're not using depth testing
+  glGenRenderbuffersEXT(1, &depthBuffer);
+  glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, depthBuffer);
+  glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT24,  width, height);
+  REPORTGLERROR("creating depth render buffer");
+
+  // Render buffer to use for imaging
+  glGenRenderbuffersEXT(1, &renderBuffer);
+  glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, renderBuffer);
+  glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_RGBA8, width, height);
+  REPORTGLERROR("creating color render buffer");
+  glGenFramebuffersEXT(1, &fbo);
+  glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo);
+  REPORTGLERROR("binding framebuffer");
+
+  glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, 
+                               GL_RENDERBUFFER_EXT, renderBuffer);
+  REPORTGLERROR("specifying color render buffer");
+
+  if (glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT) !=  GL_FRAMEBUFFER_COMPLETE_EXT) {
+		std::cerr << "Problem with OpenGL framebuffer after specifying color render buffer.\n";
+		return 0;
+  }
+
+  glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, depthBuffer);
+  REPORTGLERROR("specifying depth render buffer");
+
+  if (glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT) != GL_FRAMEBUFFER_COMPLETE_EXT) {
+		std::cerr << "Problem with OpenGL framebuffer after specifying depth render buffer.\n";
+		return 0;
+  }
+	return fbo;
+}
+
+void fbo_bind(GLuint fbo)
+{
+  glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo);
+}
+
+void fbo_unbind()
+{
+  glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+}