From 1933978cb800c2348e8891c69b28e85c9417b32d Mon Sep 17 00:00:00 2001
From: Andrei Karas <akaras@inbox.ru>
Date: Fri, 2 Mar 2012 17:17:02 +0300
Subject: Use FBO for screenshots. Disabled for windows.

---
 src/openglgraphics.cpp | 72 ++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 70 insertions(+), 2 deletions(-)

(limited to 'src/openglgraphics.cpp')

diff --git a/src/openglgraphics.cpp b/src/openglgraphics.cpp
index 242588473..684716aac 100644
--- a/src/openglgraphics.cpp
+++ b/src/openglgraphics.cpp
@@ -26,6 +26,7 @@
 
 #include "graphicsvertexes.h"
 #include "openglgraphics.h"
+#include "configuration.h"
 #include "logger.h"
 
 #include "resources/image.h"
@@ -50,8 +51,8 @@ const unsigned int vertexBufSize = 500;
 GLuint OpenGLGraphics::mLastImage = 0;
 
 OpenGLGraphics::OpenGLGraphics():
-    mAlpha(false), mTexture(false), mColorAlpha(false),
-    mSync(false)
+    mAlpha(false), mTexture(false), mColorAlpha(false), mSync(false),
+    mFboId(0), mTextureId(0), mRboId(0)
 {
     mOpenGL = 1;
     mFloatTexArray = new GLfloat[vertexBufSize * 4 + 30];
@@ -1039,6 +1040,50 @@ void OpenGLGraphics::_endDraw()
     popClipArea();
 }
 
+void OpenGLGraphics::prepareScreenshot()
+{
+#if !defined(_WIN32)
+    if (config.getBoolValue("usefbo"))
+    {
+        int h = mTarget->h;
+        int w = mTarget->w;
+
+        // create a texture object
+        glGenTextures(1, &mTextureId);
+        glBindTexture(GL_TEXTURE_2D, mTextureId);
+        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, w, h, 0,
+            GL_RGBA, GL_UNSIGNED_BYTE, 0);
+        glBindTexture(GL_TEXTURE_2D, 0);
+
+        // create a renderbuffer object to store depth info
+        glGenRenderbuffersEXT(1, &mRboId);
+        glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, mRboId);
+        glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT,
+            GL_DEPTH_COMPONENT, w, h);
+        glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, 0);
+
+        // create a framebuffer object
+        glGenFramebuffersEXT(1, &mFboId);
+        glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, mFboId);
+
+        // attach the texture to FBO color attachment point
+        glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+            GL_TEXTURE_2D, mTextureId, 0);
+
+        // attach the renderbuffer to depth attachment point
+        glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT,
+            GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, mRboId);
+
+        glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, mFboId);
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    }
+#endif
+}
+
 SDL_Surface* OpenGLGraphics::getScreenshot()
 {
     int h = mTarget->h;
@@ -1079,6 +1124,29 @@ SDL_Surface* OpenGLGraphics::getScreenshot()
 
     free(buf);
 
+#if !defined(_WIN32)
+    if (config.getBoolValue("usefbo"))
+    {
+        glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+        if (mFboId)
+        {
+            glDeleteFramebuffersEXT(1, &mFboId);
+            mFboId = 0;
+        }
+        glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, 0);
+        if (mRboId)
+        {
+            glDeleteRenderbuffersEXT(1, &mRboId);
+            mRboId = 0;
+        }
+        if (mTextureId)
+        {
+            glDeleteTextures(1, &mTextureId);
+            mTextureId = 0;
+        }
+    }
+#endif
+
     glPixelStorei(GL_PACK_ALIGNMENT, pack);
 
     if (SDL_MUSTLOCK(screenshot))
-- 
cgit v1.2.3-70-g09d2