在金属中手动设置1D纹理 [英] Manually set a 1D Texture in Metal
问题描述
我正在尝试用值手动填充 1D纹理，并将该纹理传递给计算着色器(这些是我想通过代码设置的2个像素，它们不代表任何图像).
I'm trying to fill a 1D texture with values manually and pass that texture to a compute shader (these are 2 pixels that I want to set via code, they don't represent any image).
由于当前有少量的Metal示例，我可以找到的所有示例都涉及到 2D纹理，这些2D纹理通过将已加载的UIImage转换为原始字节数据来加载纹理，但创建了虚拟UIImage对我来说就像是黑客.
Due to the current small amount of Metal examples, all examples I could find deal with 2D textures that load the texture by converting a loaded UIImage to raw bytes data, but creating a dummy UIImage felt like a hack for me.
这是我开始的天真"方式-
This is the "naive" way I started with -
...
var manualTextureData: [Float] = [ 1.0, 0.0, 0.0, 1.0,
0.0, 0.0, 1.0, 1.0 ];
let region: MTLRegion = MTLRegionMake1D(0, textureDescriptor.width);
myTexture.replaceRegion(region, mipmapLevel: 0, withBytes: &manualTextureData, bytesPerRow: 0);
但是Metal无法在着色器中识别这些值(除了第一个值，它会得到一个空的纹理).
but Metal doesn't recognize those values in the shader (it gets an empty texture, except for the first value).
我很快意识到Float数组可能必须转换为字节数组(例如UInt8)，但也找不到从[Float]转换为[UInt8]的方法.
I quickly realized that the Float array probably has to be converted into a bytes array (e.g UInt8), but couldn't find a way to convert from [Float] to [UInt8] either.
我考虑的另一个可能的选择是使用CVPixelBuffer对象，但这也感觉像是解决该问题的方法.
Another possible option I consider is using a CVPixelBuffer object, but that also felt like a workaround to the problem.
那么解决这个问题的正确方法是什么?
So whats the right way to tackle that?
谢谢.
- 请注意，我对 Objective-C 不熟悉，因此我不确定使用
CVPixelBuffer/UIImage是否会被夸大了. li>
- Please note I'm not familiar with Objective-C, hence I'm not sure whether using
CVPixelBuffer/UIImageis exaggerated for something which should be straight-forward.
推荐答案
请原谅简短的答复，但您可能会发现查看我对Swift和Metal的实验很有用.我已经在Swift中创建了一个粒子系统，该系统作为粒子结构的一维数组传递到Metal计算着色器.通过使用posix_memalign，我可以消除在Metal和Swift之间传递数组引起的瓶颈.
Please forgive the terse reply, but you may find it useful to take a look at my experiments with Swift and Metal. I've created a particle system in Swift which is passed to a Metal compute shader as a one dimensional array of Particle structs. By using posix_memalign, I'm able to eliminate the bottleneck caused by passing the array between Metal and Swift.
我对此进行了广泛的博客发布: http://flexmonkey.blogspot.co. uk/search/label/Metal
I've blogged extensively about this: http://flexmonkey.blogspot.co.uk/search/label/Metal
我希望这会有所帮助.
I hope this helps.
西蒙(Simon)
这篇关于在金属中手动设置1D纹理的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
