sf::Texture's function don't preserve the current texture binding anymore (was used to keep mixing SFML and OpenGL safe, but the potential performance loss was too high -- glGet* may trigger a glFlush)

src/SFML/Graphics/GLCheck.hpp

@@ -44,7 +44,7 @@ namespace priv
 #ifdef SFML_DEBUG
 
     // In debug mode, perform a test on every OpenGL call
-    #define GLCheck(call) ((call), priv::GLCheckError(__FILE__, __LINE__))
+#define GLCheck(call) ((call), sf::priv::GLCheckError(__FILE__, __LINE__))
 
 #else
 

src/SFML/Graphics/RenderTextureImplDefault.cpp

@@ -77,14 +77,9 @@ bool RenderTextureImplDefault::Activate(bool active)
 ////////////////////////////////////////////////////////////
 void RenderTextureImplDefault::UpdateTexture(unsigned int textureId)
 {
-    GLint previous;
-    GLCheck(glGetIntegerv(GL_TEXTURE_BINDING_2D, &previous));
-
     // Copy the rendered pixels to the texture
     GLCheck(glBindTexture(GL_TEXTURE_2D, textureId));
     GLCheck(glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, myWidth, myHeight));
-
-    GLCheck(glBindTexture(GL_TEXTURE_2D, previous));
 }
 
 } // namespace priv

src/SFML/Graphics/Shader.cpp

@@ -34,6 +34,21 @@
 #include <vector>
 
 
+////////////////////////////////////////////////////////////
+// Private data
+////////////////////////////////////////////////////////////
+namespace
+{
+    // Retrieve the maximum number of texture units available
+    GLint GetMaxTextureUnits()
+    {
+        GLint maxUnits;
+        GLCheck(glGetIntegerv(GL_MAX_TEXTURE_COORDS_ARB, &maxUnits));
+        return maxUnits;
+    }
+}
+
+
 namespace sf
 {
 ////////////////////////////////////////////////////////////
@@ -244,8 +259,7 @@ void Shader::SetTexture(const std::string& name, const Texture& texture)
         if (it == myTextures.end())
         {
             // New entry, make sure there are enough texture units
-            GLint maxUnits;
+            static const GLint maxUnits = GetMaxTextureUnits();
-            GLCheck(glGetIntegerv(GL_MAX_TEXTURE_COORDS_ARB, &maxUnits));
             if (myTextures.size() + 1 >= static_cast<std::size_t>(maxUnits))
             {
                 Err() << "Impossible to use texture \"" << name << "\" for shader: all available texture units are used" << std::endl;

src/SFML/Graphics/Texture.cpp

@@ -121,10 +121,6 @@ bool Texture::Create(unsigned int width, unsigned int height)
         myTexture = static_cast<unsigned int>(texture);
     }
 
-    // Save the current texture binding
-    GLint previous;
-    GLCheck(glGetIntegerv(GL_TEXTURE_BINDING_2D, &previous));
-
     // Initialize the texture
     GLCheck(glBindTexture(GL_TEXTURE_2D, myTexture));
     GLCheck(glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, myTextureWidth, myTextureHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL));
@@ -133,9 +129,6 @@ bool Texture::Create(unsigned int width, unsigned int height)
     GLCheck(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, myIsSmooth ? GL_LINEAR : GL_NEAREST));
     GLCheck(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, myIsSmooth ? GL_LINEAR : GL_NEAREST));
 
-    // Restore the previous texture
-    GLCheck(glBindTexture(GL_TEXTURE_2D, previous));
-
     return true;
 }
 
@@ -200,10 +193,6 @@ bool Texture::LoadFromImage(const Image& image, const IntRect& area)
         // Create the texture and upload the pixels
         if (Create(rectangle.Width, rectangle.Height))
         {
-            // Save the current texture binding
-            GLint previous;
-            GLCheck(glGetIntegerv(GL_TEXTURE_BINDING_2D, &previous));
-
             // Copy the pixels to the texture, row by row
             const Uint8* pixels = image.GetPixelsPtr() + rectangle.Left + (width * rectangle.Top);
             GLCheck(glBindTexture(GL_TEXTURE_2D, myTexture));
@@ -212,10 +201,6 @@ bool Texture::LoadFromImage(const Image& image, const IntRect& area)
                 GLCheck(glTexSubImage2D(GL_TEXTURE_2D, 0, 0, i, myWidth, 1, GL_RGBA, GL_UNSIGNED_BYTE, pixels));
                 pixels += width;
             }
-            myPixelsFlipped = false;
-
-            // Restore the previous texture
-            GLCheck(glBindTexture(GL_TEXTURE_2D, previous));
 
             return true;
         }
@@ -250,10 +235,6 @@ Image Texture::CopyToImage() const
 
     EnsureGlContext();
 
-    // Save the previous texture
-    GLint previous;
-    GLCheck(glGetIntegerv(GL_TEXTURE_BINDING_2D, &previous));
-
     // Create an array of pixels
     std::vector<Uint8> pixels(myWidth * myHeight * 4);
 
@@ -293,9 +274,6 @@ Image Texture::CopyToImage() const
         }
     }
 
-    // Restore the previous texture
-    GLCheck(glBindTexture(GL_TEXTURE_2D, previous));
-
     // Create the image
     Image image;
     image.Create(myWidth, myHeight, &pixels[0]);
@@ -322,17 +300,10 @@ void Texture::Update(const Uint8* pixels, unsigned int width, unsigned int heigh
     {
         EnsureGlContext();
 
-        // Save the current texture binding
-        GLint previous;
-        GLCheck(glGetIntegerv(GL_TEXTURE_BINDING_2D, &previous));
-
         // Copy pixels from the given array to the texture
         GLCheck(glBindTexture(GL_TEXTURE_2D, myTexture));
         GLCheck(glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height, GL_RGBA, GL_UNSIGNED_BYTE, pixels));
         myPixelsFlipped = false;
-
-        // Restore the previous texture
-        GLCheck(glBindTexture(GL_TEXTURE_2D, previous));
     }
 }
 
@@ -367,17 +338,10 @@ void Texture::Update(const Window& window, unsigned int x, unsigned int y)
 
     if (myTexture && window.SetActive(true))
     {
-        // Save the current texture binding
-        GLint previous;
-        GLCheck(glGetIntegerv(GL_TEXTURE_BINDING_2D, &previous));
-
         // Copy pixels from the back-buffer to the texture
         GLCheck(glBindTexture(GL_TEXTURE_2D, myTexture));
         GLCheck(glCopyTexSubImage2D(GL_TEXTURE_2D, 0, x, y, 0, 0, window.GetWidth(), window.GetHeight()));
         myPixelsFlipped = true;
-
-        // Restore the previous texture
-        GLCheck(glBindTexture(GL_TEXTURE_2D, previous));
     }
 }
 
@@ -400,14 +364,9 @@ void Texture::SetSmooth(bool smooth)
         {
             EnsureGlContext();
 
-            GLint previous;
-            GLCheck(glGetIntegerv(GL_TEXTURE_BINDING_2D, &previous));
-
             GLCheck(glBindTexture(GL_TEXTURE_2D, myTexture));
             GLCheck(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, myIsSmooth ? GL_LINEAR : GL_NEAREST));
             GLCheck(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, myIsSmooth ? GL_LINEAR : GL_NEAREST));
-
-            GLCheck(glBindTexture(GL_TEXTURE_2D, previous));
         }
     }
 }