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POTexture coordinates for a skybox
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copied!<p>I'm attempting to map a sky box texture that looks like <a href="http://www.keithlantz.net/wp-content/uploads/2011/10/skybox_texture.jpg" rel="nofollow">this</a></p> <p>I am creating a 3d cube that is drawn using GL_TRIANGLES and have 8 vertices and 8 colors for the vertices. I can post the code if need be. </p> <pre><code>bool Skybox::onInitialize() { myRadius = 100; setPosition(Vector3(0.0f, 2.0f, 0.0f)); //Initialize color matrix myColors.push_back(Color(1.0f, 0.0f, 0.0f, 1.0f)); myColors.push_back(Color(1.0f, 1.0f, 0.0f, 1.0f)); myColors.push_back(Color(1.0f, 0.5f, 0.0f, 1.0f)); myColors.push_back(Color(0.5f, 0.5f, 0.5f, 1.0f)); myColors.push_back(Color(1.0f, 0.0f, 0.0f, 1.0f)); myColors.push_back(Color(1.0f, 1.0f, 0.0f, 1.0f)); myColors.push_back(Color(1.0f, 0.5f, 0.0f, 1.0f)); myColors.push_back(Color(0.5f, 0.5f, 0.5f, 1.0f)); //Position the key points of the cube myVertices.push_back(Vertex(-myRadius, -myRadius, myRadius));//0 myVertices.push_back(Vertex(-myRadius, -myRadius, -myRadius));//1 myVertices.push_back(Vertex(myRadius, -myRadius, -myRadius));//2 myVertices.push_back(Vertex(myRadius, -myRadius, myRadius));//3 myVertices.push_back(Vertex(-myRadius, myRadius, myRadius));//4 myVertices.push_back(Vertex(-myRadius, myRadius, -myRadius));//5 myVertices.push_back(Vertex( myRadius, myRadius, -myRadius));//6 myVertices.push_back(Vertex( myRadius, myRadius, myRadius));//7 //Push back the indices that make up the triangles for each face. //Bottom myIndices.push_back(3); myIndices.push_back(2); myIndices.push_back(0); myIndices.push_back(2); myIndices.push_back(1); myIndices.push_back(0); //Top myIndices.push_back(4); myIndices.push_back(6); myIndices.push_back(7); myIndices.push_back(4); myIndices.push_back(5); myIndices.push_back(6); //Front myIndices.push_back(1); myIndices.push_back(4); myIndices.push_back(0); myIndices.push_back(1); myIndices.push_back(5); myIndices.push_back(4); //Back myIndices.push_back(3); myIndices.push_back(6); myIndices.push_back(2); myIndices.push_back(3); myIndices.push_back(7); myIndices.push_back(6); //Side myIndices.push_back(5); myIndices.push_back(1); myIndices.push_back(6); myIndices.push_back(1); myIndices.push_back(2); myIndices.push_back(6); //Side myIndices.push_back(4); myIndices.push_back(7); myIndices.push_back(0); myIndices.push_back(7); myIndices.push_back(3); myIndices.push_back(0); ////Generate Texture Coordinates //Bottom myTexCoords.push_back(TexCoord(0.25, 0)); myTexCoords.push_back(TexCoord(0.25, 0.375)); myTexCoords.push_back(TexCoord(0.5, 0.375)); myTexCoords.push_back(TexCoord(0.5, 0)); //Top myTexCoords.push_back(TexCoord(0.25, 1)); myTexCoords.push_back(TexCoord(0.25, 0.625)); myTexCoords.push_back(TexCoord(0.5, 0.625)); myTexCoords.push_back(TexCoord(0.5, 1)); ////Left //myTexCoords.push_back(TexCoord(0, 0.625)); //myTexCoords.push_back(TexCoord(0.25, 0.625)); //myTexCoords.push_back(TexCoord(0.25, 0.375)); //myTexCoords.push_back(TexCoord(0, 0.375)); ////Right //myTexCoords.push_back(TexCoord(0.5, 0.625)); //myTexCoords.push_back(TexCoord(0.75, 0.625)); //myTexCoords.push_back(TexCoord(0.75, 0.375)); //myTexCoords.push_back(TexCoord(0.5, 0.375)); ////Back //myTexCoords.push_back(TexCoord(0.75, 0.625)); //myTexCoords.push_back(TexCoord(1.0, 0.625)); //myTexCoords.push_back(TexCoord(1.0, 0.375)); //myTexCoords.push_back(TexCoord(0.75, 0.375)); const string vertexShader = (GLSLProgram::glsl130Supported()) ? VERTEX_SHADER_130 : VERTEX_SHADER_120; const string fragmentShader = (GLSLProgram::glsl130Supported()) ? FRAGMENT_SHADER_130 : FRAGMENT_SHADER_120; if (!myTexture.load(SKY_TEXTURE)) { std::cerr << "Could not load the particle texture" << std::endl; return false; } glGenTextures(1, &myTexID); glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, myTexID); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, myTexture.getWidth(), myTexture.getHeight(), 0, GL_RGBA, GL_UNSIGNED_BYTE, myTexture.getImageData()); m_shaderProgram = std::auto_ptr<GLSLProgram>(new GLSLProgram(vertexShader, fragmentShader)); if (!m_shaderProgram->initialize()) { std::cerr << "Could not load the skybox shaders" << std::endl; return false; } m_shaderProgram->bindAttrib(0, "a_Vertex"); m_shaderProgram->bindAttrib(1, "a_Color"); m_shaderProgram->bindAttrib(2, "a_TexCoord0"); m_shaderProgram->linkProgram(); //m_shaderProgram->sendUniform("texture0", 0); glGenBuffers(1, &myVertexBuffer); //Generate a buffer for the vertices glBindBuffer(GL_ARRAY_BUFFER, myVertexBuffer); //Bind the vertex buffer glBufferData(GL_ARRAY_BUFFER, sizeof(Vector3) * myVertices.size(), &myVertices[0], GL_STATIC_DRAW); //Send the data to OpenGL glGenBuffers(1, &myColorBuffer); glBindBuffer(GL_ARRAY_BUFFER, myColorBuffer); glBufferData(GL_ARRAY_BUFFER, sizeof(Color) * myColors.size(), &myColors[0], GL_STATIC_DRAW); //Send the data to OpenGL glGenBuffers(1, &myTexCoordBuffer); glBindBuffer(GL_ARRAY_BUFFER, myTexCoordBuffer); glBufferData(GL_ARRAY_BUFFER, sizeof(TexCoord) * myTexCoords.size(), &myTexCoords[0], GL_STATIC_DRAW); //Send the data to OpenGL glGenBuffers(1, &myIndexBuffer); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, myIndexBuffer); //Bind the vertex buffer glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(GLuint) * myIndices.size(), &myIndices[0], GL_STATIC_DRAW); //Send the data to OpenGL return true; </code></pre> <p>}</p>

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