What does glVertexAttribPointer do?
The glVertexAttribPointer functions indicate where an attribute index gets its array data from. But it also defines how OpenGL should interpret that data. So these functions conceptually do two things: set the buffer object’s information about the source of the data, and define the format of that data.
Table of Contents
What is a vertex in OpenGL?
A vertex in OpenGL is the coordinate of a point in space AND the associated attributes (color, texture coordinate, etc.) of that point.
What is an OpenGL vao?
A vertex array object (or VAO) is an object that describes how vertex attributes are stored in a vertex buffer object (or VBO). This means that the VAO is not the actual object that stores the vertex data, but the vertex data descriptor.
What is the shader that handles color pixels in a shape called?
vertex shaders
The pixel shader is another programmable feature that allows flexibility in shading an individual pixel. While vertex shaders can be used to completely transform the shape of an object, pixel shaders are used to change the appearance of pixels.
What is the second variable in glvertexattribpointer?
The second glVertexAttribPointer defines the second variable “texCoord” as a pair of texture coordinates, each of which is a float. So if my understanding is correct so far, I assumed that we need to bind the vertex buffer object first, but even after commenting out this line
Why are there two glvertexattribpointer lines in the vertex shader?
So we have two glVertexAttribPointer lines because we have two variables defined in the vertex shader. So we’re basically defining what these two variables point to. So the first glVertexAttribPointer defines that the first “position” variable is a vertex with three coordinates each floating.
What is the purpose of glvertexattribpointer in VBO?
The purpose of glVertexAttribPointer is to define the format of the data in the vertex buffer object. So in vbo store data as follows
How to enable and disable generic vertex attribute array?
To enable and disable a generic vertex attribute array, call glEnableVertexAttribArray and glDisableVertexAttribArray with index . If enabled, the generic vertex attribute array is used when glDrawArrays , glMultiDrawArrays , glDrawElements , glMultiDrawElements , or glDrawRangeElements are called.