Extend FBO support.

Use FBO only if it supported.
Use better FBO functions if possible.

8 files changed, 154 insertions, 11 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 0ce99f292..a048fa30e 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -594,6 +594,8 @@ SET(SRCS
     map.h
     maplayer.cpp
     maplayer.h
+    mgl.cpp
+    mgl.h
     normalopenglgraphics.cpp
     normalopenglgraphics.h
     particle.cpp
diff --git a/src/Makefile.am b/src/Makefile.am
index 699caf64c..60c1a3659 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -607,6 +607,8 @@ manaplus_SOURCES += gui/widgets/avatarlistbox.cpp \
 	      map.h \
 	      maplayer.cpp \
 	      maplayer.h \
+	      mgl.cpp \
+	      mgl.h \
 	      normalopenglgraphics.cpp\
 	      normalopenglgraphics.h \
 	      particle.cpp \
diff --git a/src/client.cpp b/src/client.cpp
index e35a6eca8..5d43afbf5 100644
--- a/src/client.cpp
+++ b/src/client.cpp
@@ -534,6 +534,7 @@ void Client::gameInit()
     applyVSync();
 
     graphicsManager.setVideoMode();
+    graphicsManager.initOpenGLFunctions();
 
     applyGrabMode();
     applyGamma();
diff --git a/src/graphics.cpp b/src/graphics.cpp
index 43e73f236..2700df10a 100644
--- a/src/graphics.cpp
+++ b/src/graphics.cpp
@@ -173,6 +173,7 @@ bool Graphics::setOpenGLMode()
     logger->log1(glExtensions);
 
     graphicsManager.updateExtensions(glExtensions);
+    graphicsManager.setGLVersion();
 
     graphicsManager.updateTextureFormat();
     updateMemoryInfo();
diff --git a/src/graphicsmanager.cpp b/src/graphicsmanager.cpp
index d18b79c41..79830294e 100644
--- a/src/graphicsmanager.cpp
+++ b/src/graphicsmanager.cpp
@@ -20,10 +20,17 @@
 
 #include "graphicsmanager.h"
 
+#define GL_GLEXT_PROTOTYPES 1
+#include "GL/glx.h"
+// hack to hide warnings
+#undef GL_GLEXT_VERSION
+#undef GL_GLEXT_PROTOTYPES
+
 #include "configuration.h"
 #include "graphics.h"
 #include "graphicsvertexes.h"
 #include "logger.h"
+#include "mgl.h"
 
 #include "resources/fboinfo.h"
 #include "resources/imagehelper.h"
@@ -176,7 +183,6 @@ void GraphicsManager::initGraphics(bool noOpenGL)
             mainGraphics = new SafeOpenGLGraphics;
             break;
     };
-
 #else
     // Create the graphics context
     imageHelper = new SDLImageHelper;
@@ -284,6 +290,11 @@ std::string GraphicsManager::getGLString(int num) const
 #endif
 }
 
+void GraphicsManager::setGLVersion()
+{
+    sscanf(getGLString(GL_VERSION).c_str(), "%5d.%5d", &mMajor, &mMinor);
+}
+
 void GraphicsManager::setVideoMode()
 {
     const int width = config.getIntValue("screenwidth");
@@ -348,25 +359,25 @@ void GraphicsManager::createFBO(int width, int height, FBOInfo *fbo)
     glBindTexture(GL_TEXTURE_2D, 0);
 
     // create a renderbuffer object to store depth info
-    glGenRenderbuffersEXT(1, &fbo->rboId);
-    glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, fbo->rboId);
-    glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT,
+    mglGenRenderbuffers(1, &fbo->rboId);
+    mglBindRenderbuffer(GL_RENDERBUFFER, fbo->rboId);
+    mglRenderbufferStorage(GL_RENDERBUFFER,
         GL_DEPTH_COMPONENT, width, height);
-    glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, 0);
+    mglBindRenderbuffer(GL_RENDERBUFFER, 0);
 
     // create a framebuffer object
-    glGenFramebuffersEXT(1, &fbo->fboId);
-    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo->fboId);
+    mglGenFramebuffers(1, &fbo->fboId);
+    mglBindFramebuffer(GL_FRAMEBUFFER, fbo->fboId);
 
     // attach the texture to FBO color attachment point
-    glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+    mglFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
         GL_TEXTURE_2D, fbo->textureId, 0);
 
     // attach the renderbuffer to depth attachment point
-    glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT,
-        GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, fbo->rboId);
+    mglFramebufferRenderbuffer(GL_FRAMEBUFFER,
+        GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, fbo->rboId);
 
-    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo->fboId);
+    mglBindFramebuffer(GL_FRAMEBUFFER, fbo->fboId);
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 #endif
 }
@@ -396,3 +407,40 @@ void GraphicsManager::deleteFBO(FBOInfo *fbo)
     }
 #endif
 }
+
+#ifdef WIN32
+#define getFunction(name) wglGetProcAddress(name);
+#else
+#define getFunction(name) glXGetProcAddress((const GLubyte*)(name))
+#endif
+
+void GraphicsManager::initOpenGLFunctions()
+{
+    if (!checkGLVersion(1, 1))
+        return;
+
+    if (supportExtension("GL_ARB_framebuffer_object"))
+    {   // frame buffer supported
+        mglGenRenderbuffers = (glGenRenderbuffers_t)getFunction("glGenRenderbuffers");
+        mglBindRenderbuffer = (glBindRenderbuffer_t)getFunction("glBindRenderbuffer");
+        mglRenderbufferStorage = (glRenderbufferStorage_t)getFunction("glRenderbufferStorage");
+        mglGenFramebuffers = (glGenFramebuffers_t)getFunction("glGenFramebuffers");
+        mglBindFramebuffer = (glBindFramebuffer_t)getFunction("glBindFramebuffer");
+        mglFramebufferTexture2D = (glFramebufferTexture2D_t)getFunction("glFramebufferTexture2D");
+        mglFramebufferRenderbuffer = (glFramebufferRenderbuffer_t)getFunction("glFramebufferRenderbuffer");
+    }
+    else if (supportExtension("GL_EXT_framebuffer_object"))
+    {   // old frame buffer extension
+        mglGenRenderbuffers = (glGenRenderbuffers_t)getFunction("glGenRenderbuffersEXT");
+        mglBindRenderbuffer = (glBindRenderbuffer_t)getFunction("glBindRenderbufferEXT");
+        mglRenderbufferStorage = (glRenderbufferStorage_t)getFunction("glRenderbufferStorageEXT");
+        mglGenFramebuffers = (glGenFramebuffers_t)getFunction("glGenFramebuffersEXT");
+        mglBindFramebuffer = (glBindFramebuffer_t)getFunction("glBindFramebufferEXT");
+        mglFramebufferTexture2D = (glFramebufferTexture2D_t)getFunction("glFramebufferTexture2DEXT");
+        mglFramebufferRenderbuffer = (glFramebufferRenderbuffer_t)getFunction("glFramebufferRenderbufferEXT");
+    }
+    else
+    {   // no frame buffer support
+        config.setValue("usefbo", false);
+    }
+}
diff --git a/src/graphicsmanager.h b/src/graphicsmanager.h
index a82739bc5..9b7a40a29 100644
--- a/src/graphicsmanager.h
+++ b/src/graphicsmanager.h
@@ -51,6 +51,8 @@ class GraphicsManager
 
         std::string getGLString(int num) const;
 
+        void setGLVersion();
+
         void setVideoMode();
 
         bool checkGLVersion(int major, int minor) const;
@@ -59,6 +61,8 @@ class GraphicsManager
 
         void deleteFBO(FBOInfo *fbo);
 
+        void initOpenGLFunctions();
+
     private:
         std::set<std::string> mExtensions;
 
diff --git a/src/mgl.cpp b/src/mgl.cpp
new file mode 100644
index 000000000..856a3575c
--- /dev/null
+++ b/src/mgl.cpp
@@ -0,0 +1,33 @@
+/*
+ *  The ManaPlus Client
+ *  Copyright (C) 2012  The ManaPlus Developers
+ *
+ *  This file is part of The ManaPlus Client.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "mgl.h"
+
+#include "localconsts.h"
+
+#define defName(name) name##_t m##name = nullptr
+
+defName(glGenRenderbuffers);
+defName(glBindRenderbuffer);
+defName(glRenderbufferStorage);
+defName(glGenFramebuffers);
+defName(glBindFramebuffer);
+defName(glFramebufferTexture2D);
+defName(glFramebufferRenderbuffer);
diff --git a/src/mgl.h b/src/mgl.h
new file mode 100644
index 000000000..3721c6a9f
--- /dev/null
+++ b/src/mgl.h
@@ -0,0 +1,52 @@
+/*
+ *  The ManaPlus Client
+ *  Copyright (C) 2012  The ManaPlus Developers
+ *
+ *  This file is part of The ManaPlus Client.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef MGL_H
+#define MGL_H
+
+#define GL_GLEXT_PROTOTYPES 1
+
+#include <SDL_opengl.h>
+#include <GL/glext.h>
+
+#define defNameE(name) extern name##_t m##name
+
+typedef void (APIENTRY *glGenRenderbuffers_t)(GLsizei, GLuint *);
+typedef void (APIENTRY *glBindRenderbuffer_t)(GLenum target,
+    GLuint renderbuffer);
+typedef void (APIENTRY *glRenderbufferStorage_t)(GLenum target,
+    GLenum internalformat, GLsizei width, GLsizei height);
+typedef void (APIENTRY *glGenFramebuffers_t)(GLsizei n, GLuint *framebuffers);
+typedef void (APIENTRY *glBindFramebuffer_t)(GLenum target,
+    GLuint framebuffer);
+typedef void (APIENTRY *glFramebufferTexture2D_t)(GLenum target,
+    GLenum attachment, GLenum textarget, GLuint texture, GLint level);
+typedef void (APIENTRY *glFramebufferRenderbuffer_t)(GLenum target,
+    GLenum attachment, GLenum renderbuffertarget, GLuint renderbuffer);
+
+defNameE(glGenRenderbuffers);
+defNameE(glBindRenderbuffer);
+defNameE(glRenderbufferStorage);
+defNameE(glGenFramebuffers);
+defNameE(glBindFramebuffer);
+defNameE(glFramebufferTexture2D);
+defNameE(glFramebufferRenderbuffer);
+
+#endif