Alessandro Pasotti b89808f573 [opencl] Small optimization in hillshade
... and more tolerant epsilon for float comparison in tests
2018-08-08 09:26:30 +02:00

57 lines
2.1 KiB
Common Lisp

#include "calcfirstder.cl"
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
__kernel void processNineCellWindow( __global float *scanLine1,
__global float *scanLine2,
__global float *scanLine3,
__global float *resultLine,
__global float *rasterParams // mInputNodataValue, mOutputNodataValue, mZFactor, mCellSizeX, mCellSizeY, zenith_rad, azimuth_rad
)
{
// Get the index of the current element
const int i = get_global_id(0);
if ( scanLine2[i+1] == rasterParams[0] )
{
resultLine[i] = rasterParams[1];
}
else
{
float derX = calcFirstDer( scanLine1[i], scanLine1[i+1], scanLine1[i+2],
scanLine2[i], scanLine2[i+1], scanLine2[i+2],
scanLine3[i], scanLine3[i+1], scanLine3[i+2],
rasterParams[0], rasterParams[1], rasterParams[2], rasterParams[3] );
float derY = calcFirstDer( scanLine3[i], scanLine2[i], scanLine1[i],
scanLine3[i+1], scanLine2[i+1], scanLine1[i+1],
scanLine3[i+2], scanLine2[i+2], scanLine1[i+2],
rasterParams[0], rasterParams[1], rasterParams[2], rasterParams[4]);
if ( derX == rasterParams[1] || derY == rasterParams[1] )
{
resultLine[i] = rasterParams[1];
}
else
{
float slope_rad = sqrt( derX * derX + derY * derY );
slope_rad = atan( slope_rad );
float aspect_rad;
if ( derX == 0.0f && derY == 0.0f)
aspect_rad = rasterParams[7] / 2.0f;
else
aspect_rad = M_PI + atan2( derX, derY );
resultLine[i] = max(0.0f, 255.0f * ( ( rasterParams[5] * cos( slope_rad ) ) +
( rasterParams[6] * sin( slope_rad ) *
cos( rasterParams[7] - aspect_rad ) ) ) );
}
}
}