How to use compute shader in Brook+

Discussion created by rexiaoyu on Aug 14, 2009
Latest reply on Aug 16, 2009 by rexiaoyu

To use the compute shader, I know I should use Attribute to specify thread group size and then do data sharing ..... But I still get confused when I get into the actual code, for example, I wanna use compute shader to do simple array addition, and each thread process multiple elements. I wrote the following code, but it seems I got index out of range problem. Anyone can fix it ?



Attribute[GroupSize(64, 1, 1)]

kernel void

blockAdd(float a[], float b[], out float c[])


int tid = instance().x;

//every thread process len elements, len =  1, 2, 4,.....

int len= 2;


int start = tid * len;

int i;

for (i = 0; i < len; i++)


c[start + i] = a[start + i] + b[start + i];