code: func ClearTexSubImage(texture uint32, level int32, xoffset int32, yoffset int32, zoffset int32, width int32, height int32, depth int32, format uint32, xtype uint32, data unsafe.Pointer) {
  	syscall.Syscall12(gpClearTexSubImage, 11, uintptr(texture), uintptr(level), uintptr(xoffset), uintptr(yoffset), uintptr(zoffset), uintptr(width), uintptr(height), uintptr(depth), uintptr(format), uintptr(xtype), uintptr(data), 0)
  }
docs: // fills all or part of a texture image with a constant value