Line by line rendering


Sorry, my english not very good.

I’m writing 3D editor, and I need to render image in portions, first line, then second line and so on. I dont know how can i read objects only one time, and then do only rasterization.

It seems to me that you don’t understand how opengl works.
Basically, it stores all the picture in a big array (called the frame buffer), then updates this picture one triangle at a time, regardless of the position of the triangle.
It doesn’t do things line by line, that is more appropriate to ray-tracing.

If you really need to do things line by line, then you can use OpenGL to render your model, then read the picture back from the frame buffer one line at a time.
Why you would want to do this, I don’t know…

Scan line algorithm make things line to line, but this require that your model be projected to a 2d plane… I hope this help you…