A shader approach would likely do the horizontal and vertical steps in a single pass. You can probably get away with fewer draws by using multitexturing. Note the extra costs involved here: you're ostensibly adding ten full-screen textured draws plus some framebuffer swapping. Play around with them to affect the fall off towards the outside of your lines. You need to write your own shader to deal with the alpha channel since OpenGL ES 2. Those opacity numbers were derived from the 2d Gaussian kernel on this page. The texture drawn to the image buffer was just a stretched red rectangle, which as you can see is clipped to the stencil contents. apply a linear vertical blur to that by taking the horizontal blur texture and doing essentially the same steps but with y offsets instead of x offsets.As others have mentioned, this won't smooth polygon edges, but it will create antialiased lines. It may also help to set the line width to a non-integral width. Try: glEnable (GLBLEND) glBlendFunc (GLSRCALPHA, GLONEMINUSSRCALPHA) and then drawing lines. This is a common technique on console games and higher-end PC games. Draw one copy at an offset of x = 0 with opacity 1.0, draw two further copies - one at x = +1 and one at x = -1 - with opacity 0.63 and a final two copies - one at x = +2 and one at x = -2 with an opacity of 0.17. 6 Answers Sorted by: 23 You also need to turn on blending for line smoothing to work. A third approach, the one described in this article, is referred to as dynamic resolution rendering. apply a linear horizontal blur to that by taking the source texture you just rendered and drawing it, say, five times to another texture, which I'll call the horizontal blur texture.render all lines to a texture as normal, solid hairline lines.In your case you probably want just to display the Gaussian image rather than mixing it with an original since the glow is all you're interested in. Gamasutra has an (old) article on how glow was achieved in the Tron 2.0 game - you'll want to pay particular attention to the DirectX 7.0 comments since that was, like ES 1.0, a fixed pipeline. In ES 1.0 you can use render-to-texture creatively to achieve the effect that you want, but it's likely to be costly in terms of fill rate.

Opengl es 2.0 draw line