#include "PointMapGenerator.h"
#include "globals.h"

int PointMapGenerator::GeneratePointMap(IDirect3DVertexBuffer9* vertexBuffer, IDirect3DIndexBuffer9* indexBuffer, int vertexCount, int indexCount, int vertexStride, int positionOffset, int normalOffset, float distanceFromVertex, D3DXVECTOR4* outPointMap, int takeEveryNtVertex)
{
	char* vertexData;
	PMG_INDEX_FORMAT* indexData;
	vertexBuffer->Lock(0, 0, (void**)&vertexData, D3DLOCK_READONLY);
	indexBuffer->Lock(0, 0, (void**)&indexData, D3DLOCK_READONLY);

	int pointCount = GeneratePointMap(vertexData, indexData, vertexCount, indexCount, vertexStride, positionOffset, normalOffset, distanceFromVertex, outPointMap, takeEveryNtVertex);

	vertexBuffer->Unlock();
	indexBuffer->Unlock();

	return pointCount;
}


int PointMapGenerator::GeneratePointMap(char* vertexData, PMG_INDEX_FORMAT* indexData, int vertexCount, int indexCount, int vertexStride, int positionOffset, int normalOffset, float distanceFromVertex, D3DXVECTOR4* outPointMap, int takeEveryNtVertex)
{
	int pointCount = 0;

	float maxY = 0;
	float minY = 0;
	for (int i = 0; i < indexCount; ++i)
	{
		// Assertion does not hold, so what?
		if ( indexData[i] >= vertexCount )
			continue;

		assert ( indexData[i] < vertexCount );

		D3DXVECTOR3* v = (D3DXVECTOR3*)&vertexData[indexData[i] * vertexStride + positionOffset];
		if (i == 0 || maxY < v->y)
		{
			maxY = v->y;
		}
		if (i == 0 || minY > v->y)
		{
			minY = v->y;
		}
	}

	for (int i = 0; i < indexCount; i += takeEveryNtVertex)
	{
		// Assertion does not hold, so what?
		if ( indexData[i] >= vertexCount )
			continue;

		assert ( indexData[i] < vertexCount );

		D3DXVECTOR3* v = (D3DXVECTOR3*)&vertexData[indexData[i] * vertexStride + positionOffset];
		D3DXVECTOR3* n = (D3DXVECTOR3*)&vertexData[indexData[i] * vertexStride + normalOffset];
		D3DXVECTOR3 result = (*v) + (*n) * distanceFromVertex * g_Random.genFloat();
		outPointMap[pointCount++] = D3DXVECTOR4(
			result.x,
			result.y,
			result.z,
			((v->y - minY) / (maxY - minY)) * 0.2 + g_Random.genFloat(0.0f, 0.8f));
	}

	return pointCount;
}


void PointMapGenerator::FillPointMap(int pointMapIndex, int objectIndex, int fluidIndex, int takeEveryNtVertex)
{
	int pointCount = GeneratePointMap(
		g_Objects[ objectIndex ].GetVB(),
		g_Objects[ objectIndex ].GetIB(),
		g_Objects[ objectIndex ].GetVertCount(),
		g_Objects[ objectIndex ].GetIndexCount(),
		sizeof(Renderjob::SVertex),
		0,
		3 * sizeof(FLOAT),
		g_PointMapDistance[pointMapIndex],
		g_FluidPointMap[pointMapIndex],
		takeEveryNtVertex);

	assert( pointCount <= 100000 );

	g_FluidParticleSystem[fluidIndex] = g_FluidContext.GenerateFluidParticleSystem(pointCount * 4);
}