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POIf not GL_QUADS, then how?
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copied!<p>I'm developing a simple 2D game in Java using the LWJGL wrapper for OpenGL. <BR>For the rendering method, I use VBOs. It seems very good and faster the the other rendering methods.<br>I was reading some articles and was seeking for some questions here on StackOverflow and I discovered that using 2 triangles is better than using one quad, since modern GPUs show only triangles (And it'll be a waste to let the GPU translate that quad into triangles).</p> <p>The only way I know is creating 2 buffers for storing the vertex data and the texture coordinates data. and that's for a quad, this is how I do it:</p> <pre><code>int vertexID; //Holding the GL buffer ID for the Vertex int texCoordsID; //Holding the GL buffer ID for the texture coords void init(){ //BufferUtils is a Utility class provided by the SlickUtil library, I use it for creating buffers. //Create float buffer for storing vertex data FloatBuffer vertexBuffer = BufferUtils.createFloatBuffer(4 * 2); //Put vertex data inside the buffer vertexBuffer.put(new float[]{ 0, 0, 100, 0, 100, 100, 0, 100 }); //Rewind the buffer vertexBuffer.rewind(); FloatBuffer texCoordsBuffer = BufferUtils.createFloatBuffer(4 * 2); texCoordsBuffer.put(new float[]{ 0, 0, 1, 0, 1, 1, 0, 1 }); texCoordsBuffer.rewind(); vertexID = glGenBuffers(); glBindBuffer(GL_ARRAY_BUFFER, vertexID); glBufferData(GL_ARRAY_BUFFER, vertexBuffer, GL_STATIC_DRAW); glBindBuffer(GL_ARRAY_BUFFER, 0); texCoordsID = glGenBuffers(); glBindBuffer(GL_ARRAY_BUFFER, texCoordsID); glBufferData(GL_ARRAY_BUFFER, texCoordsBuffer, GL_STATIC_DRAW); glBindBuffer(GL_ARRAY_BUFFER, 0); } void render(){ glBindTexture(GL_TEXTURE_2D, texture.id); //Not so important. glBindBuffer(GL_ARRAY_BUFFER, vertexID); glVertexPointer(2, GL_FLOAT, 0, 0); glBindBuffer(GL_ARRAY_BUFFER, texCoordsID); glTexCoordPointer(2, GL_FLOAT, 0, 0); glEnableClientState(GL_VERTEX_ARRAY); glEnableClientState(GL_TEXTURE_COORD_ARRAY); glDrawArrays(GL_QUADS, 0, 4); glDisableClientState(GL_VERTEX_ARRAY); glDisableClientState(GL_TEXTURE_COORD_ARRAY); } </code></pre> <p>Now my main question is, how can you split it into 2 triangles instead of 1 quad?<br> And a side question: does it really matter for a 2D game? does it make a slight change?</p>

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