SDL: Performance SPriG vs SDL_gfx

Question

Hi,

I need to draw a polygon with thick lines. Now I have two possibilities:

• Draw them with the library SPriG, which provides line thickness.
• Split up the polygon in all it lines and draw them as polygons with a modified thickness _{(like explained in this tutorial (1 tutorial on the page).)} with the SDL_gfx library.

I'm not sure about the performance of SPriG. SDL_gfx will be the fastest I guess.
Did you ever tried this, or simply "do you know the quality of SPrig"?

Thanks

Answer 1

It looks like SPriG just draws a circle at each pixel along a line to give it thickness. For wide lines you're looking at quite a bit of overdraw.

I'd do it a bit differently. It may or may not be faster depending on how triangle rasterization compares to per-pixel circle overdraw.