src/PSkelStencilTiling.h

//-------------------------------------------------------------------------------
// Copyright (c) 2015, ICEI - PUC Minas
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
// 
// 1. Redistributions of source code must retain the above copyright notice, this
// list of conditions and the following disclaimer.
// 
// 2. Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
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// 3. Neither the name of the copyright holder nor the names of its contributors
// may be used to endorse or promote products derived from this software without
// specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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//-------------------------------------------------------------------------------

#ifndef PSKEL_STENCIL_TILING_H
#define PSKEL_STENCIL_TILING_H

namespace PSkel{

template<class Array, class Mask>
class StencilTiling {
public:
        Mask mask;
        Array input;
        Array output;
        
        size_t iterations;

        //global offsets that define the tiling
        //necessary for the given iterations,
        //i.e., including the halo region (neighbourhood margin)
        size_t widthOffset;
        size_t heightOffset;
        size_t depthOffset;
        size_t width;
        size_t height;
        size_t depth;

        //core offsets represent the inner margin
        //that consist of the halo region (neighbourhood) for 
        //the given iterations
        size_t coreWidthOffset;
        size_t coreHeightOffset;
        size_t coreDepthOffset;
        size_t coreWidth;
        size_t coreHeight;
        size_t coreDepth;

        StencilTiling(Array in, Array out, Mask mask){
                this->input = in;
                this->output = out;
                this->mask = mask;
        }

        void tile(size_t iterations, size_t widthOffset, size_t heightOffset, size_t depthOffset, size_t width, size_t height, size_t depth){
                this->iterations = iterations;
                //check for unaligned tiling
                if((widthOffset+width)>this->input.getWidth())
                        width = this->input.getWidth()-widthOffset;
                if((heightOffset+height)>this->input.getHeight())
                        height = this->input.getHeight()-heightOffset;
                if((depthOffset+depth)>this->input.getDepth())
                        depth = this->input.getDepth()-depthOffset;

                this->coreWidthOffset = widthOffset; //temporary value of core width offset
                this->coreHeightOffset = heightOffset; //temporary value of core height offset
                this->coreDepthOffset = depthOffset; //temporary value of core depth offset
                this->coreWidth = width; //set the width for the logical tile region
                this->coreHeight = height; //set the height for the logical tile region
                this->coreDepth = depth; //set the depth for the logical tile region
                
                size_t maskRange = mask.getRange()*iterations;

                int widthExtra = 0;
                int heightExtra = 0;
                int depthExtra = 0;

                if(widthOffset>=maskRange){
                        widthOffset=widthOffset-maskRange;
                }else{
                        widthOffset = 0;
                        widthExtra = maskRange-widthOffset;
                }
                width = width+(maskRange*2)-widthExtra;
                if((widthOffset+width)>this->input.getWidth())
                        width = this->input.getWidth()-widthOffset;

                if(heightOffset>=maskRange){
                        heightOffset=heightOffset-maskRange;
                }else{
                        heightOffset = 0;
                        heightExtra = maskRange-heightOffset;
                }
                height = height+(maskRange*2)-heightExtra;
                if((heightOffset+height)>this->input.getHeight())
                        height = this->input.getHeight()-heightOffset;

                if(depthOffset>=maskRange){
                        depthOffset=depthOffset-maskRange;
                }else{
                        depthOffset = 0;
                        depthExtra = maskRange-depthOffset;
                }
                depth = depth+(maskRange*2)-depthExtra;
                if((depthOffset+depth)>this->input.getDepth())
                        depth = this->input.getDepth()-depthOffset;
                
                this->coreWidthOffset -= widthOffset; //final value of core width offset
                this->coreHeightOffset -= heightOffset; //final value of core height offset
                this->coreDepthOffset -= depthOffset; //final value of core depth offset
                
                this->widthOffset = widthOffset;
                this->heightOffset = heightOffset;
                this->depthOffset = depthOffset;
                this->width = width;
                this->height = height;
                this->depth = depth;
        }
};

}

#endif