CUDA 三维纹理的创建和使用测试

CUDA 复杂问题 + 细节问题 解答 见 CUDA复杂问题 + 细节问题 解答

首先放上代码：

#include "cuda_runtime.h"
#include "device_launch_parameters.h"
#include "cuda.h"
#include <iostream>
using std::cout;
using std::endl;
#define arrayNum 100
#define mwidth 10
#define mheight 10
#define mlength 10
texture<short, 3, cudaReadModeNormalizedFloat> texVolumeData;  // 3D texture
cudaArray *d_volumeArray = 0;
void textureVolumeDataInit(void) {

	short* texturedata = (short*)malloc(mwidth*mlength*mlength*sizeof(short));
	for (int i = 0;i < mwidth*mlength*mlength;i++) {
		texturedata[i] = i;
	}
	// --- Create 3D array
	const cudaExtent volumeSize = make_cudaExtent(mwidth, mheight, mlength);
	cudaChannelFormatDesc channelDesc = cudaCreateChannelDesc<short>();
	cudaMalloc3DArray(&d_volumeArray, &channelDesc, volumeSize);

	// --- Copy data to 3D array (host to device)
	cudaMemcpy3DParms copyParams = { 0 };
	copyParams.srcPtr = make_cudaPitchedPtr((void*)texturedata, volumeSize.width * sizeof(short), volumeSize.width, volumeSize.height);
	copyParams.dstArray = d_volumeArray;
	copyParams.extent = volumeSize;
	copyParams.kind = cudaMemcpyHostToDevice;
	cudaMemcpy3D(&copyParams);

	// --- Set texture parameters
	texVolumeData.normalized = false;                      // access with normalized texture coordinates
	texVolumeData.filterMode = cudaFilterModeLinear;      // linear interpolation
	texVolumeData.addressMode[0] = cudaAddressModeWrap;   // wrap texture coordinates
	texVolumeData.addressMode[1] = cudaAddressModeWrap;
	texVolumeData.addressMode[2] = cudaAddressModeWrap;

	// --- Bind array to 3D texture
	cudaBindTextureToArray(texVolumeData, d_volumeArray, channelDesc);

	free(texturedata);
}

__global__ void cudaTest(float *c)
{
	int x = threadIdx.x + blockIdx.x * blockDim.x;
	int y = threadIdx.y + blockIdx.y * blockDim.y;
	c[x + y * blockDim.x * gridDim.x] = 65535.0/2.0*tex3D(texVolumeData, (float)(x+0.5), (float)(y+0.5),0+0.5);
}
int main()
{
	float *dev_c = 0;
	float *c = 0;
	c = (float*)malloc(arrayNum * sizeof(float));
	cudaMalloc((void**)&dev_c, arrayNum * sizeof(float));
	textureVolumeDataInit();

	dim3    blocks(2, 2);
	dim3    threads(5, 5);
	cudaTest << <blocks, threads >> >(dev_c);

	cudaMemcpy(c, dev_c, arrayNum * sizeof(float), cudaMemcpyDeviceToHost);
	for (int i = 0;i < arrayNum;i++) {
		cout << c[i] << endl;
	}

	system("pause");
    return 0;
}

注意几点：

这里收集到的数据是规范化的，所以需要乘一个比例系数：65535/2.0。如果是unsigned short类型的数据，就是65535了。

65535.0/2.0*tex3D(texVolumeData, (float)(x+0.5), (float)(y+0.5),0+0.5);