请尊重原作者的工作，转载时请务必注明转载自：www.xionggf.com 原文地址 Partial difference derivative functions (ddx and ddy in HLSL[a], dFdx and dFdy in GLSL[b]) (in the rest of this article I will use both terms according to the code examples I will provide) are fragment shader instructions wich can be used to compute the rate of variation of any value with respect to the screen-space coordinates. 偏导数函数（在HLSL中为ddx和ddy，GLSL中为dFdx和dFdy）。在本文的其余部分中，我将根据我将提供的代码示例使用这两个术语）都是可以使用的片元着色器指令，可用于计算任何数值相对于 屏幕空间坐标 的变化率。 Derivatives computation During triangles rasterization, GPUs run many instances of a fragment shader at a time organizing them in blocks of 2×2 pixels.

请尊重原作者的工作，转载时请务必注明转载自：www.xionggf.com 原文地址： http://www.learnopengl.com/#!In-Practice/Debugging 1 Debugging Graphics programming can be a lot of fun, but it can also be a large source of frustration whenever something isn’t rendering right or perhaps not even rendering at all! Seeing as most of what we do involves manipulating pixels it can be difficult to figure out the cause of error whenever something doesn’t work the way it’s supposed to. Debugging these kind of errors is different than what you’re used to when debugging errors on the CPU.