domain_gather.br

来自「用于GPU通用计算的编程语言BrookGPU 0.4」· BR 代码 · 共 60 行

// domain_gather.br

// test that gathering from a domain works

#include <stdio.h>

kernel void gatherFetch( float2 index<>, float2 g[][], out float2 result<> )
{
	result = g[ index ];
}

int main()
{
	int i, j;
	float x, y;
	float2 indexStream< 100 >;
	float2 gatherStream< 20, 20 >;
	float2 resultStream< 100 >;
	
	float2 index_data[ 100 ];
	float2 gather_data[ 20 ][ 20 ];
	float2 result_data[ 100 ];

	// initialize index data
	for( i = 0; i < 100; i++ )
	{
		index_data[ i ].x = (float)( i % 10 );
		index_data[ i ].y = (float)( i / 10 );
	}
	
	// initialize gather data
	for( i = 0; i < 20; i++ )
	for( j = 0; j < 20; j++ )
	{
		gather_data[ i ][ j ].x = (float)i;
		gather_data[ i ][ j ].y = (float)j;
	}
	
	streamRead( indexStream, index_data );
	streamRead( gatherStream, gather_data );
	
	gatherFetch( indexStream, gatherStream.domain( int2( 0, 7 ), int2( 10, 17 ) ), resultStream );
	
	streamWrite( resultStream, result_data );
	
	for( i = 0; i < 10; i++ )
	{
		for( j = 0; j < 10; j++ )
		{
			x = result_data[ j*10 + i ].x;
			y = result_data[ j*10 + i ].y;
			
			printf( "<%f %f> ", x, y );
		}
		printf( "\n" );
	}
	
	return 0;
}