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POOpenGL Textures form SDLSurface goes too dark
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copied!<p>I've quite the same problem than this <a href="https://stackoverflow.com/questions/13670259/opengl-texture-goes-too-dark">OpenGl goes too dark</a> but the answer doesn't work for me. I'm trying to display a image thanks to a surface converted to a texture and the result is too damn dark:</p> <p>Original:</p> <p><img src="https://i.stack.imgur.com/YGbNa.png" alt="enter image description here"> </p> <p>after openGL</p> <p><img src="https://i.stack.imgur.com/JyMup.png" alt="enter image description here"></p> <p>On the left is the original, on the right the OpenGl img.</p> <p>Here's my code:</p> <pre><code>void TexturedRect::draw(int scroll){ glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glBindTexture(GL_TEXTURE_2D, _texture); glEnable(GL_TEXTURE_2D); glBegin(GL_QUADS); //Begining the cube's drawing int x = this->getX(); int y = this->getY(); int w = this->getWidth(); int h = this->getHeight(); int z = this->getZ(); /* (0,0) ------ (1,0) | | | | (0,1) ------ (1,1) */ glTexCoord3i(0, 0, 1);glVertex3i(x + scroll, y, z); glTexCoord3i(_tv, 0, 1);glVertex3i(x + w * _tv + scroll, y, z); glTexCoord3i(_tv, _tu, 1);glVertex3i(x + w * _tv + scroll, y + h * _tu, z); glTexCoord3i(0, _tu, 1);glVertex3i(x + scroll, y + h * _tu, z); glEnd(); glDisable(GL_TEXTURE_2D); } void TexturedRect::createTextureFromSurface() { SDL_Surface * surface = IMG_Load(filename.toStdString().c_str()); // get the number of channels in the SDL surface GLint nbOfColors = surface->format->BytesPerPixel; GLenum textureFormat = 0; switch (nbOfColors) { case 1: textureFormat = GL_ALPHA; break; case 3: // no alpha channel if (surface->format->Rmask == 0x000000ff) textureFormat = GL_RGB; else textureFormat = GL_BGR; break; case 4: // contains an alpha channel if (surface->format->Rmask == 0x000000ff) textureFormat = GL_RGBA; else textureFormat = GL_BGRA; break; default: qDebug() << "Warning: the image is not truecolor..."; break; } glEnable( GL_TEXTURE_2D ); // Have OpenGL generate a texture object handle for us glGenTextures( 1, &_texture ); // Bind the texture object glBindTexture( GL_TEXTURE_2D, _texture ); // Edit the texture object's image data using the information SDL_Surface gives us glTexImage2D( GL_TEXTURE_2D, 0, nbOfColors, surface->w, surface->h, 0, textureFormat, GL_UNSIGNED_BYTE, surface->pixels ); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); } </code></pre>

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