vertex-buffer

I have OpenGL code using one VAO for all model data and two VBOs. The first for standard vertex attributes like position and normal and the second for the model matrices. I am using instanced draw, so I load the model matrices as instanced arrays (which are basically vertex attributes). First I load the standard vertex attributes to a VBO and setup everything once with glVertexAttribPointer . Then I load the model matrices to another VBO. Now I have to call glVertexAttribPointer in the draw loop. Can I somehow prevent this? The code looks like this: // vertex data of all models in one array

I have trouble rendering some geometry by using a vertex buffer object. I intend to draw a plane of points, so basically one vertex at every discrete position in my space. However, I cannot render that plane, as every time I call glDrawElements(...), application crashes returning an access violation exception. There must be some mistake while initialization, I guess. This is what I have so far: #define SPACE_X 512 #define SPACE_Z 512 typedef struct{ GLfloat x, y, z; // position GLfloat nx, ny, nz; // normals GLfloat r, g, b, a; // colors } Vertex; typedef struct{ GLuint i; // index } Index; //

I'm currently using the GLTools classes that come along with the Superbible 5th edition. I'm looking in the GLTriangleBatch class and it has the following code: // Create the master vertex array object glGenVertexArrays(1, &vertexArrayBufferObject); glBindVertexArray(vertexArrayBufferObject); // Create the buffer objects glGenBuffers(4, bufferObjects); #define VERTEX_DATA 0 #define NORMAL_DATA 1 #define TEXTURE_DATA 2 #define INDEX_DATA 3 // Copy data to video memory // Vertex data glBindBuffer(GL_ARRAY_BUFFER, bufferObjects[VERTEX_DATA]); glEnableVertexAttribArray(GLT_ATTRIBUTE_VERTEX);

I'm working through the excellent tutorials at arcsynthesis while building a graphics engine and have discovered I don't understand VAOs as much as I thought I had. From the tutorial Chapter 5. Objects In Depth Buffer Binding and Attribute Association You may notice that glBindBuffer(GL_ARRAY_BUFFER) is not on that list, even though it is part of the attribute setup for rendering. The binding to GL_ARRAY_BUFFER is not part of a VAO because the association between a buffer object and a vertex attribute does not happen when you call glBindBuffer(GL_ARRAY_BUFFER). This association happens when

When I update my vertex array on iOS in OpenGL 2.0, the original vertex data is staying on the screen -- ie the 1st flush is persistent (the initial set of points I sent down to the GPU gets rendered every frame), but the 2nd, 3rd, 4th, .. nth flushes all seem to overwrite the same memory. So I'm doing: vector<VertexType> rawDynamicData ; glGenVertexArraysOES( 1, &va ) ; CHECK_GL ; glBindVertexArrayOES( va ) ; CHECK_GL ; glGenBuffers( 1, &vb ) ; CHECK_GL ; glBindBuffer( GL_ARRAY_BUFFER, vb ) ; CHECK_GL ; glBufferData( glBufferData( GL_ARRAY_BUFFER, //Specifies the target buffer object.

So here is a previous question: How to implement a ShaderToy shader in three.js Tried to implement the steps from the link above into this code unsucessfully: three.js/blob/master/examples/webgl_shader.html So I replaced the original vertex shader and the origianl fragment shader so I got this code: <script id="vertexShader" type="x-shader/x-vertex"> varying vec2 vUv; void main() { vUv = uv; vec4 mvPosition = modelViewMatrix * vec4(position, 1.0 ); gl_Position = projectionMatrix * mvPosition; } </script> <script id="fragmentShader" type="x-shader/x-fragment"> uniform float iGlobalTime; uniform

I want to send a buffer list (to the GPU/vertex shader) which contains information about vertex position, world position, color, scale, and rotation. If each of my 3D objects have transformation related information in a matrix, how can i pass this array of matrices (in addition to the other vertex data) to the GPU via the VBO(s) ? Updated Please excuse any typos: // bind & set vertices. gl.bindBuffer(gl.ARRAY_BUFFER, vertexBuffer); gl.vertexAtribPointer(a_Position, 3, gl.FLOAT, false, stride, 0); // bind & set vertex normals. gl.bindBuffer(gl.ARRAY_BUFFER,, vertexNormalsBuffer); gl