fix some graphics issues on Windows virtualbox

src/framework/graphics/framebuffer.cpp

@@ -45,7 +45,7 @@ FrameBuffer::FrameBuffer(int width, int height)
     m_texture->enableBilinearFilter();
 
     // use FBO ext only if supported
-    if(false && g_graphics.isExtensionSupported("GL_ARB_framebuffer_object")) {
+    if(g_graphics.isExtensionSupported("GL_ARB_framebuffer_object")) {
         m_fallbackOldImp = false;
         if(!oglGenFramebuffers) {
             oglGenFramebuffers = (PFNGLGENFRAMEBUFFERSPROC)g_platform.getExtensionProcAddress("glGenFramebuffers");
@@ -106,7 +106,7 @@ void FrameBuffer::bind()
     glLoadIdentity();
 
     // clear framebuffer
-    glClearColor(0.0, 0.0, 0.0, 0.0);
+    glClearColor(0.0, 0.0, 0.0, 1.0);
     glClear(GL_COLOR_BUFFER_BIT);
 }
 
@@ -136,5 +136,5 @@ void FrameBuffer::unbind()
 
 void FrameBuffer::draw(const Rect& screenCoords, const Rect& framebufferCoords)
 {
-    g_graphics.drawTexturedRect(screenCoords, m_texture ,framebufferCoords);
+    g_graphics.drawTexturedRect(screenCoords, m_texture, framebufferCoords);
 }

src/framework/graphics/graphics.cpp

@@ -148,18 +148,18 @@ void Graphics::drawTexturedRect(const Rect& screenCoords,
     float textureBottom;
     float textureTop;
     float textureLeft;
+    const Size& textureSize = texture->getGlSize();
 
     if(textureCoords.isEmpty()) {
-        textureRight = 1.0f;
-        textureBottom = 1.0f;
+        textureRight = texture->getWidth() / (float)textureSize.width();
+        textureBottom = texture->getHeight()  / (float)textureSize.height();
         textureTop = 0.0f;
         textureLeft = 0.0f;
     } else {
-        const Size& textureSize = texture->getGlSize();
-        textureRight = (float)(textureCoords.right() + 1) / textureSize.width();
-        textureBottom = (float)(textureCoords.bottom() + 1) / textureSize.height();
-        textureTop = (float)textureCoords.top() / textureSize.height();
-        textureLeft = (float)textureCoords.left() / textureSize.width();
+        textureRight = (textureCoords.right() + 1) / (float)textureSize.width();
+        textureBottom = (textureCoords.bottom() + 1) / (float)textureSize.height();
+        textureTop = textureCoords.top() / (float)textureSize.height();
+        textureLeft = textureCoords.left() / (float)textureSize.width();
     }
 
     if(!m_drawing) {

src/framework/graphics/texture.cpp

@@ -72,7 +72,7 @@ uint Texture::internalLoadGLTexture(uchar *pixels, int channels, int width, int
     std::vector<uint8> tmp;
 
     // old opengl drivers only accept power of two dimensions
-    if(!g_graphics.isExtensionSupported("GL_ARB_texture_non_power_of_two") && pixels) {
+    if(!g_graphics.isExtensionSupported("GL_ARB_texture_non_power_of_two")) {
         int glWidth = 1;
         while(glWidth < width)
             glWidth = glWidth << 1;
@@ -81,13 +81,12 @@ uint Texture::internalLoadGLTexture(uchar *pixels, int channels, int width, int
         while(glHeight < height)
             glHeight = glHeight << 1;
 
-        if(m_size != m_glSize) {
+        if(m_size != m_glSize && pixels) {
             tmp.resize(glHeight*glWidth*channels, 0);
-            if(pixels)
-                for(int y=0; y<height; ++y)
-                    for(int x=0; x<width; ++x)
-                        for(int i=0; i<channels; ++i)
-                            tmp[y*glWidth*channels+x*channels+i] = pixels[y*width*channels+x*channels+i];
+            for(int y=0; y<height; ++y)
+                for(int x=0; x<width; ++x)
+                    for(int i=0; i<channels; ++i)
+                        tmp[y*glWidth*channels+x*channels+i] = pixels[y*width*channels+x*channels+i];
             pixels = &tmp[0];
         }
 

src/framework/platform/win32platform.cpp

@@ -419,9 +419,11 @@ bool Platform::isExtensionSupported(const char *ext)
     typedef const char* _wglGetExtensionsStringARB(HDC hdc);
     _wglGetExtensionsStringARB *wglGetExtensionsStringARB = (_wglGetExtensionsStringARB*)getExtensionProcAddress("wglGetExtensionsStringARB");
 
-    const char *exts = wglGetExtensionsStringARB(win32.hdc);
-    if(strstr(exts, ext))
-        return true;
+    if(wglGetExtensionsStringARB) {
+        const char *exts = wglGetExtensionsStringARB(win32.hdc);
+        if(strstr(exts, ext))
+            return true;
+    }
     return false;
 }