dolphin/Source/Plugins/Plugin_VideoDX9/Src/PixelShaderCache.cpp

// Copyright (C) 2003-2008 Dolphin Project.

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/

#include "D3DBase.h"
#include "Statistics.h"
#include "Utils.h"
#include "Profiler.h"
#include "PixelShaderCache.h"
#include "VertexLoader.h"
#include "BPMemory.h"
#include "XFMemory.h"

PShaderCache::PSCache PShaderCache::pshaders;

//I hope we don't get too many hash collisions :p
//all these magic numbers are primes, it should help a bit
tevhash GetCurrentTEV()
{
	u32 hash = bpmem.genMode.numindstages + bpmem.genMode.numtevstages*11 + bpmem.genMode.numtexgens*8*17;
	for (int i = 0; i < (int)bpmem.genMode.numtevstages+1; i++)
	{
		hash = _rotl(hash,3) ^ (bpmem.combiners[i].colorC.hex*13);
		hash = _rotl(hash,7) ^ ((bpmem.combiners[i].alphaC.hex&0xFFFFFFFC)*3);
		hash = _rotl(hash,9) ^ xfregs.texcoords[i].texmtxinfo.projection*451;
	}
	for (int i = 0; i < (int)bpmem.genMode.numtevstages/2+1; i++)
	{
		hash = _rotl(hash,13) ^ (bpmem.tevorders[i].hex*7);
	}
	for (int i = 0; i < 8; i++)
	{
		hash = _rotl(hash,3) ^ bpmem.tevksel[i].swap1;
		hash = _rotl(hash,3) ^ bpmem.tevksel[i].swap2;
	}
	hash ^= bpmem.dstalpha.enable ^ 0xc0debabe;
	hash = _rotl(hash,4) ^ bpmem.alphaFunc.comp0*7;
	hash = _rotl(hash,4) ^ bpmem.alphaFunc.comp1*13;
	hash = _rotl(hash,4) ^ bpmem.alphaFunc.logic*11;
	return hash;
}


void PShaderCache::Init()
{

}


void PShaderCache::Shutdown()
{
	PSCache::iterator iter = pshaders.begin();
	for (;iter!=pshaders.end();iter++)
		iter->second.Destroy();
	pshaders.clear(); 
}


void PShaderCache::SetShader()
{
	if (D3D::GetShaderVersion() < 2)
		return; // we are screwed

	static LPDIRECT3DPIXELSHADER9 lastShader = 0;
    DVSTARTPROFILE();

	tevhash currentHash = GetCurrentTEV();

	PSCache::iterator iter;
	iter = pshaders.find(currentHash);
	
	if (iter != pshaders.end())
	{
		iter->second.frameCount = frameCount;
		PSCacheEntry &entry = iter->second;
		if (!lastShader || entry.shader != lastShader)
		{
			D3D::dev->SetPixelShader(entry.shader);
			lastShader = entry.shader;
		}
		return;
	}

	const char *code = GeneratePixelShader();
	LPDIRECT3DPIXELSHADER9 shader = D3D::CompilePShader(code, int(strlen(code)));
	if (shader)
	{
		//Make an entry in the table
		PSCacheEntry newentry;
		newentry.shader = shader;
		newentry.frameCount = frameCount;
		pshaders[currentHash] = newentry;
	}

	D3D::dev->SetPixelShader(shader);

	INCSTAT(stats.numPixelShadersCreated);
	SETSTAT(stats.numPixelShadersAlive, (int)pshaders.size());
}

void PShaderCache::Cleanup()
{
	PSCache::iterator iter;
	iter = pshaders.begin();

	while (iter != pshaders.end())
	{
		PSCacheEntry &entry = iter->second;
		if (entry.frameCount < frameCount-30)
		{
			entry.Destroy();
			iter = pshaders.erase(iter);
		}
		else
		{
			iter++;
		}
	}
	SETSTAT(stats.numPixelShadersAlive, (int)pshaders.size());
}