/*******************************************************************************
* The MIT License (MIT)
*
* Copyright (c) 2015 Matthew Williams and David Williams
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* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
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* SOFTWARE.
*******************************************************************************/

#include "TestAmbientOcclusionGenerator.h"

#include "PolyVox/AmbientOcclusionCalculator.h"
#include "PolyVox/FilePager.h"
#include "PolyVox/PagedVolume.h"
#include "PolyVox/RawVolume.h"

#include <QtTest>

using namespace PolyVox;

class IsVoxelTransparent
{
public:
	bool operator()(uint8_t voxel) const
	{
		return voxel == 0;
	}
};

bool isVoxelTransparentFunction(uint8_t voxel)
{
	return voxel == 0;
}

void TestAmbientOcclusionGenerator::testExecute()
{
	const int32_t g_uVolumeSideLength = 64;
	Region region(0, 0, 0, g_uVolumeSideLength - 1, g_uVolumeSideLength - 1, g_uVolumeSideLength - 1);

	//Create empty volume
	RawVolume<uint8_t> volData(region);

	// To test with a PagedVolume instead you can comment ou the above line and use these instead.
	// FilePager<uint8_t>* pFilePager = new FilePager<uint8_t>(".");
	// PagedVolume<uint8_t> volData(pFilePager, 256 * 1024 * 1024, 32);

	//Create two solid walls at opposite sides of the volume
	for (int32_t z = 0; z < g_uVolumeSideLength; z++)
	{
		if((z < 20) || (z > g_uVolumeSideLength - 20))
		{
			for (int32_t y = 0; y < g_uVolumeSideLength; y++)
			{
				for (int32_t x = 0; x < g_uVolumeSideLength; x++)
				{
					volData.setVoxel(x, y, z, 1);
				}
			}
		}
	}

	//Create an array to store the result. Array can be smaller than the volume by an integer amount.
	const int32_t g_uArraySideLength = g_uVolumeSideLength / 2;
	Array<3, uint8_t> ambientOcclusionResult(g_uArraySideLength, g_uArraySideLength, g_uArraySideLength);

	// Calculate the ambient occlusion values
	IsVoxelTransparent isVoxelTransparent;
	QBENCHMARK {
		calculateAmbientOcclusion(&volData, &ambientOcclusionResult, region, 32.0f, 255, isVoxelTransparent);
	}
	
	//Check the results by sampling along a line though the centre of the volume. Because
	//of the two walls we added, samples in the middle are darker than those at the edge.
	QCOMPARE(static_cast<int>(ambientOcclusionResult(16,  0, 16)), 178);
	QCOMPARE(static_cast<int>(ambientOcclusionResult(16,  8, 16)), 109);
	QCOMPARE(static_cast<int>(ambientOcclusionResult(16, 16, 16)), 103);
	QCOMPARE(static_cast<int>(ambientOcclusionResult(16, 24, 16)), 123);
	QCOMPARE(static_cast<int>(ambientOcclusionResult(16, 31, 16)), 173);
	
	//Just run a quick test to make sure that it compiles when taking a function pointer
	calculateAmbientOcclusion(&volData, &ambientOcclusionResult, region, 32.0f, 8, &isVoxelTransparentFunction);
	
	//Also test it using a lambda
	//calculateAmbientOcclusion(&volData, &ambientOcclusionResult, volData.getEnclosingRegion(), 32.0f, 8, [](uint8_t voxel){return voxel == 0;});
}

QTEST_MAIN(TestAmbientOcclusionGenerator)