From 033baf5710cc021acc93ff7dfce6eff6c2e26cd9 Mon Sep 17 00:00:00 2001
From: Andrei Karas <akaras@inbox.ru>
Date: Fri, 2 Mar 2012 21:47:15 +0300
Subject: Add FBO for screenshots to safe opengl also.

---
 src/opengl1graphics.cpp | 75 +++++++++++++++++++++++++++++++++++++++++++++++--
 src/opengl1graphics.h   |  5 ++++
 2 files changed, 78 insertions(+), 2 deletions(-)

diff --git a/src/opengl1graphics.cpp b/src/opengl1graphics.cpp
index ea4d5e6f3..0386b4c7d 100644
--- a/src/opengl1graphics.cpp
+++ b/src/opengl1graphics.cpp
@@ -25,6 +25,7 @@
 #ifdef USE_OPENGL
 #include "opengl1graphics.h"
 
+#include "configuration.h"
 #include "graphicsvertexes.h"
 #include "logger.h"
 
@@ -46,8 +47,8 @@
 GLuint OpenGL1Graphics::mLastImage = 0;
 
 OpenGL1Graphics::OpenGL1Graphics():
-    mAlpha(false), mTexture(false), mColorAlpha(false),
-    mSync(false)
+    mAlpha(false), mTexture(false), mColorAlpha(false), mSync(false),
+    mFboId(0), mTextureId(0), mRboId(0)
 {
     mOpenGL = 2;
 }
@@ -493,6 +494,50 @@ void OpenGL1Graphics::_endDraw()
     popClipArea();
 }
 
+void OpenGL1Graphics::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* OpenGL1Graphics::getScreenshot()
 {
     int h = mTarget->h;
@@ -504,6 +549,9 @@ SDL_Surface* OpenGL1Graphics::getScreenshot()
             w, h, 24,
             0xff0000, 0x00ff00, 0x0000ff, 0x000000);
 
+    if (!screenshot)
+        return nullptr;
+
     if (SDL_MUSTLOCK(screenshot))
         SDL_LockSurface(screenshot);
 
@@ -530,6 +578,29 @@ SDL_Surface* OpenGL1Graphics::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))
diff --git a/src/opengl1graphics.h b/src/opengl1graphics.h
index 6ed2d7440..5a2d6c254 100644
--- a/src/opengl1graphics.h
+++ b/src/opengl1graphics.h
@@ -129,6 +129,8 @@ class OpenGL1Graphics : public Graphics
          */
         SDL_Surface *getScreenshot();
 
+        void prepareScreenshot();
+
         static void bindTexture(GLenum target, GLuint texture);
 
         static GLuint mLastImage;
@@ -140,6 +142,9 @@ class OpenGL1Graphics : public Graphics
         bool mAlpha, mTexture;
         bool mColorAlpha;
         bool mSync;
+        GLuint mFboId;
+        GLuint mTextureId;
+        GLuint mRboId;
 };
 #endif
 
-- 
cgit v1.2.3-70-g09d2