Dynamic VBO in OpenGL

Question

What is the best way to store dynamic data for use in VBO (or vertex arrays). Only the examples I saw were 2D static arrays, and the pointer to this array was used with the following parameters as a step, bytes used for one element, etc. I can use "dynamic" arrays, so I can specify its size on the air, but only once. I want to say that if, for example, you have already drawn 1000 points (speaking of 2D, so I think the point is better than the top) as a strip line, and you add a new point, so you need to create a new array of size 1001 , copy everything from the old to the new field, add a new point and send it to the graphic memory. The best way is to use vectors or deques as temporary storage, but then I need to convert to an array and send it again.

So is there a better way to do this? Can I add a new part to VBO without sending old data? Or the best way to store data / use a vector as a data source without conversion?

Answer 1

I usually use the ole vector trick:

struct GL_Vertex { Eigen::Vector2f tex; Eigen::Vector3f color; Eigen::Vector3f pos; }; ... vector<GL_Vertex> buf(1000); ... glTexCoordPointer( 2, GL_FLOAT, sizeof(GL_Vertex), &buf[0].tex ); glColorPointer( 3, GL_FLOAT, sizeof(GL_Vertex), &buf[0].color ); glVertexPointer( 3, GL_FLOAT, sizeof(GL_Vertex), &buf[0].pos );