在 iOS 上使用 OpenGL ES 模拟多边形点画
我想用简单的重复图案填充凹多边形。我已经可以正确绘制多边形，不幸的是我在填充它时遇到问题。在 OpenGL 中，我可以使用 POLYGON_STIPPLE 轻松完成此操作。然而，此功能在 OpenGL ES 中不可用。
我想我可能需要使用纹理而不是点画。然而，我无法弄清楚如何计算正确的纹理坐标，因为所有三角形的大小完全不同，但我仍然希望图案能够很好地彼此相邻。
是否有任何好的起点来解释如何使用重复纹理填充多边形，其中多边形比三角形或矩形稍微复杂一点？
I want to fill a concave polygon with a simple repeating pattern. I can already draw the polygon properly, unfortunately I am having problems with filling it. In OpenGL I could do this easily with POLYGON_STIPPLE. However this functionality is not available in OpenGL ES.
I figured that I probably need to use textures instead of stippling. However I cannot figure out how to calculate the correct texture coordinates as all the triangles are of completely different sizes, but I still want the pattern to fit well right next to each other.
Are there any good starting points that explain how to fill polygons with a repeating texture, where the polygon is a little more complex than one triangle or rectangle?
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计算纹理坐标并不像我想象的那么难。用图案填充多边形可以这样完成：
设置纹理参数，以便纹理重复自身。这将产生这样的效果：对于每个大于 1 的坐标，纹理将再次重复。
计算纹理坐标。每个顶点坐标c对应一个纹理坐标，计算如下： (cx/texture.width, cy/texture.height)
Calculating the texture coordinates is not as hard as I thought. Filling the polygon with a pattern can be done like this:
Set texture parameter so that texture repeats itself. This will have the effect, that for every coordinate bigger than 1 the texture will just repeat all over again.
Calculate texture coordinates. Each vertix coordinate c corresponds to a texture coordinate calculated like this: (c.x/texture.width, c.y/texture.height)