What is the best way to draw multiple objects in modern OpenGL?

Question

I'm trying to use modern OpenGL and shaders, and not the mode that I have used so far. I recently learned about VBOs and VAO, and I'm still trying to get around them, but I know that VBO accepts an array of floats that are vertices that are then passed to the GPU, etc.

What is the best way to draw multiple objects (they are all identical), but in different positions using VBOs. Do I have to draw one, and then modify the array passed in advance, and then draw it again and change, draw and change, etc ... for all the blocks on the screen in each frame? Or is there a better way?

I am trying to achieve this: http://imgur.com/cBgJ0sK

Any help is appreciated - I don't want to learn the bad (obsolete, old) regime habits, when I could learn a more modern way!

Answer 1

You should not change the vertices in your program, which should be executed in shaders. To do this, you will create a matrix that represents the transformation, and will use this matrix in the vertex shader.

Main idea:

You create a VAO that stores your VBO data (vertices, normals, texture coordinates, tangent information, etc.)

Then, for each other object, you create a model matrix that contains information about position, orientation and scale (and other homogeneous transformations) and sends them to your shader for conversion.

, VAO , , , ( , ), .

, , : http://ogldev.atspace.co.uk/www/tutorial06/tutorial06.html

, .

, , - instancing. http://ogldev.atspace.co.uk/www/tutorial33/tutorial33.html

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