//===== Copyright (c) 1996-2005, Valve Corporation, All rights reserved. ======//
//
// r_studio.cpp: routines for setting up to draw 3DStudio models 
//
// $Workfile:     $
// $Date:         $
// $NoKeywords: $
//===========================================================================//


#include "studio.h"
#include "studiorender.h"
#include "studiorendercontext.h"
#include "optimize.h"
#include "materialsystem/imaterial.h"
#include "materialsystem/imaterialvar.h"
#include "tier0/vprof.h"
#include "tier3/tier3.h"
#include "datacache/imdlcache.h"

// memdbgon must be the last include file in a .cpp file!!!
#include "tier0/memdbgon.h"

//-----------------------------------------------------------------------------
// Figures out what kind of lighting we're gonna want
//-----------------------------------------------------------------------------
FORCEINLINE StudioModelLighting_t CStudioRender::R_StudioComputeLighting( IMaterial *pMaterial, int materialFlags, ColorMeshInfo_t *pColorMeshes )
{
	// Here, we only do software lighting when the following conditions are met.
	// 1) The material is vertex lit and we don't have hardware lighting
	// 2) We're drawing an eyeball
	// 3) We're drawing mouth-lit stuff

	// FIXME: When we move software lighting into the material system, only need to
	// test if it's vertex lit

	Assert( pMaterial );
	bool doMouthLighting = materialFlags && (m_pStudioHdr->nummouths >= 1);

	if ( IsGameConsole() )
	{
		// Console does not do software lighting
		return doMouthLighting ? LIGHTING_MOUTH : LIGHTING_HARDWARE;
	}

	bool doSoftwareLighting = doMouthLighting ||
		(pMaterial && pMaterial->IsVertexLit() && pMaterial->NeedsSoftwareLighting() );

	StudioModelLighting_t lighting = LIGHTING_HARDWARE;
	if ( doMouthLighting )
		lighting = LIGHTING_MOUTH;
	else if ( doSoftwareLighting )
		lighting = LIGHTING_SOFTWARE;

	return lighting;
}


IMaterial* CStudioRender::R_StudioSetupSkinAndLighting( IMatRenderContext *pRenderContext, int index, IMaterial **ppMaterials, int materialFlags,  
	void /*IClientRenderable*/ *pClientRenderable, ColorMeshInfo_t *pColorMeshes, StudioModelLighting_t &lighting )
{
	VPROF( "R_StudioSetupSkin" );
	IMaterial *pMaterial = NULL;
	bool bCheckForConVarDrawTranslucentSubModels = false;
	bool translucent;
	if( m_pRC->m_Config.bWireframe && !m_pRC->m_pForcedMaterial[ 0 ] )
	{
		// Initially, assume no displacement mapping 
		pMaterial = m_pMaterialWireframe[m_pRC->m_Config.bDrawZBufferedWireframe?1:0][0];
		translucent = false;

		// Look to see if the original material is displacement mapped
		IMaterial *pOriginalMaterial = ppMaterials[index];
		static unsigned int originalDisplacementMap = 0;
		IMaterialVar* pOriginalMaterialVar = pOriginalMaterial->FindVarFast( "$displacementmap", &originalDisplacementMap );

		// If we are displacement mapped
		if ( pOriginalMaterialVar && pOriginalMaterialVar->IsTexture() )
		{
			// Switch to displacement mapped wireframe material
			pMaterial = m_pMaterialWireframe[m_pRC->m_Config.bDrawZBufferedWireframe?1:0][1];

			static unsigned int newDisplacementMap = 0;
			IMaterialVar* pNewMaterialVar = pMaterial->FindVarFast( "$displacementmap", &newDisplacementMap );

			if ( pNewMaterialVar )
			{
				pNewMaterialVar->SetTextureValue( pOriginalMaterialVar->GetTextureValue() );
			}
		}
	}
	else if( m_pRC->m_Config.bShowEnvCubemapOnly )
	{
		pMaterial = m_pMaterialModelEnvCubemap;
		translucent = false;
	}
	else
	{
		if ( ( !m_pRC->m_pForcedMaterial[ 0 ] && ( m_pRC->m_nForcedMaterialType != OVERRIDE_DEPTH_WRITE && m_pRC->m_nForcedMaterialType != OVERRIDE_SSAO_DEPTH_WRITE ) ) 
			 || m_pRC->m_nForcedMaterialType == OVERRIDE_SELECTIVE )
		{
			int nOverrideIndex = GetForcedMaterialOverrideIndex( index );
			if ( m_pRC->m_nForcedMaterialType == OVERRIDE_SELECTIVE && nOverrideIndex != -1 )
			{
				pMaterial = m_pRC->m_pForcedMaterial[ nOverrideIndex ];
			}
			else
			{
				pMaterial = ppMaterials[index];
			}
			if ( !pMaterial )
			{
				Assert( 0 );
				return 0;
			}

			translucent = pMaterial->IsTranslucentUnderModulation( m_pRC->m_AlphaMod );
		}
		else
		{
			materialFlags = 0;
			pMaterial = m_pRC->m_pForcedMaterial[ 0 ];
			if (m_pRC->m_nForcedMaterialType == OVERRIDE_BUILD_SHADOWS)
			{
				// Connect the original material up to the shadow building material
				// Also bind the original material so its proxies are in the correct state
				static unsigned int translucentCache = 0;
				IMaterialVar* pOriginalMaterialVar = pMaterial->FindVarFast( "$translucent_material", &translucentCache );
				Assert( pOriginalMaterialVar );
				IMaterial *pOriginalMaterial = ppMaterials[index];
				if ( pOriginalMaterial )
				{
					pRenderContext->Bind( pOriginalMaterial, pClientRenderable );
					if ( pOriginalMaterial->IsTranslucentUnderModulation() || pOriginalMaterial->IsAlphaTested() )
					{
						pOriginalMaterialVar->SetMaterialValue( pOriginalMaterial );
					}
					else
					{
						pOriginalMaterialVar->SetMaterialValue( NULL );
					}
				}
				else
				{
					pOriginalMaterialVar->SetMaterialValue( NULL );
				}
				translucent = pMaterial->IsTranslucentUnderModulation( m_pRC->m_AlphaMod );
			}
			else if ( m_pRC->m_nForcedMaterialType == OVERRIDE_DEPTH_WRITE || m_pRC->m_nForcedMaterialType == OVERRIDE_SSAO_DEPTH_WRITE )
			{
				// Bail if the material is still considered translucent after setting the AlphaModulate to 1.0
				if ( ppMaterials[index]->IsTranslucentUnderModulation() )
					return NULL;

				bool bIsAlphaTested = false;
				bool bUsesTreeSway = false;
				GetDepthWriteMaterial( &pMaterial, &bIsAlphaTested, &bUsesTreeSway, ppMaterials[ index ], false, ( m_pRC->m_nForcedMaterialType == OVERRIDE_SSAO_DEPTH_WRITE) );
				if ( bIsAlphaTested )
				{
					SetupAlphaTestedDepthWrite( pMaterial, ppMaterials[index] );
				}
				if ( bUsesTreeSway )
				{
					SetupTreeSwayDepthWrite( pMaterial, ppMaterials[index] );
				}

				translucent = false;
			}
			else
			{
				translucent = pMaterial->IsTranslucentUnderModulation( m_pRC->m_AlphaMod );
			}
		}

		// Set this bool to check after the bind below
		bCheckForConVarDrawTranslucentSubModels = true;
	}

	lighting = R_StudioComputeLighting( pMaterial, materialFlags, pColorMeshes );
	if ( lighting == LIGHTING_MOUTH )
	{
		if ( !m_pRC->m_Config.bTeeth || !R_TeethAreVisible() )
			return NULL;
		// skin it and light it, but only if we need to.
		if ( m_pRC->m_Config.m_bSupportsVertexAndPixelShaders )
		{
			R_MouthSetupVertexShader( pMaterial );
		}
	}

	pRenderContext->Bind( pMaterial, pClientRenderable );

	if ( bCheckForConVarDrawTranslucentSubModels )
	{
		if (( m_bDrawTranslucentSubModels && !translucent ) ||
			( !m_bDrawTranslucentSubModels && translucent ))
		{
			m_bSkippedMeshes = true;
			return NULL;
		}
	}

	return pMaterial;
}



//=============================================================================


/*
=================
R_StudioSetupModel
	based on the body part, figure out which mesh it should be using.
inputs:
outputs:
	pstudiomesh
	pmdl
=================
*/
int R_StudioSetupModel( int bodypart, int entity_body, mstudiomodel_t **ppSubModel, 
	const studiohdr_t *pStudioHdr )
{
	int index;
	mstudiobodyparts_t   *pbodypart;

	if (bodypart > pStudioHdr->numbodyparts)
	{
		ConDMsg ("R_StudioSetupModel: no such bodypart %d\n", bodypart);
		bodypart = 0;
	}

	pbodypart = pStudioHdr->pBodypart( bodypart );

	index = entity_body / pbodypart->base;
	index = index % pbodypart->nummodels;

	Assert( ppSubModel );
	*ppSubModel = pbodypart->pModel( index );
	return index;
}



//-----------------------------------------------------------------------------
// Generates the PoseToBone Matrix nessecary to align the given bone with the 
// world.
//-----------------------------------------------------------------------------
static void ScreenAlignBone( matrix3x4_t *pPoseToWorld, mstudiobone_t *pCurBone, 
	const Vector& vecViewOrigin, const matrix3x4_t &boneToWorld )
{
	// Grab the world translation:
	Vector vT( boneToWorld[0][3], boneToWorld[1][3], boneToWorld[2][3] );

	// Construct the coordinate frame:
	// Initialized to get rid of compiler 
	Vector vX, vY, vZ;

	if( pCurBone->flags & BONE_SCREEN_ALIGN_SPHERE )
	{
		vX = vecViewOrigin - vT;		    
		VectorNormalize(vX);
		vZ = Vector(0,0,1);
		vY = vZ.Cross(vX);				
		VectorNormalize(vY);
		vZ = vX.Cross(vY);				
		VectorNormalize(vZ);
	} 
	else
	{
		Assert( pCurBone->flags & BONE_SCREEN_ALIGN_CYLINDER );
		vX.Init( boneToWorld[0][0], boneToWorld[1][0], boneToWorld[2][0] );
		vZ = vecViewOrigin - vT;			
		VectorNormalize(vZ);
		vY = vZ.Cross(vX);				
		VectorNormalize(vY);
		vZ = vX.Cross(vY);				
		VectorNormalize(vZ);
	}

	matrix3x4_t matBoneBillboard( 
		vX.x, vY.x, vZ.x, vT.x, 
		vX.y, vY.y, vZ.y, vT.y, 
		vX.z, vY.z, vZ.z, vT.z );
	ConcatTransforms( matBoneBillboard, pCurBone->poseToBone, *pPoseToWorld );
}


//-----------------------------------------------------------------------------
// Computes PoseToWorld from BoneToWorld
//-----------------------------------------------------------------------------
void ComputePoseToWorld( matrix3x4_t *pPoseToWorld, studiohdr_t *pStudioHdr, int boneMask, const Vector& vecViewOrigin, const matrix3x4_t *pBoneToWorld )
{ 
	if ( pStudioHdr->flags & STUDIOHDR_FLAGS_STATIC_PROP )
	{
		// by definition, these always have an identity poseToBone transform
		MatrixCopy( pBoneToWorld[ 0 ], pPoseToWorld[ 0 ] );
		return;
	}

	if ( !pStudioHdr->pLinearBones() )
	{
		// convert bone to world transformations into pose to world transformations
		for (int i = 0; i < pStudioHdr->numbones; i++)
		{
			const mstudiobone_t *pCurBone = pStudioHdr->pBone( i );
			if ( !(pCurBone->flags & boneMask) )
				continue;

			ConcatTransforms( pBoneToWorld[ i ], pCurBone->poseToBone, pPoseToWorld[ i ] );
		}
	}
	else
	{
		mstudiolinearbone_t *pLinearBones = pStudioHdr->pLinearBones();

		// convert bone to world transformations into pose to world transformations
		for (int i = 0; i < pStudioHdr->numbones; i++)
		{
			if ( !(pLinearBones->flags(i) & boneMask) )
				continue;

			ConcatTransforms( pBoneToWorld[ i ], pLinearBones->poseToBone(i), pPoseToWorld[ i ] );
		}
	}

#if 0
			// These don't seem to be used in any existing QC file, re-enable in a future project?
			// Pretransform
			if( !( pCurBone->flags & ( BONE_SCREEN_ALIGN_SPHERE | BONE_SCREEN_ALIGN_CYLINDER )))
			{
				ConcatTransforms( pBoneToWorld[ i ], pCurBone->poseToBone, pPoseToWorld[ i ] );
			}
			else 
			{
				// If this bone is screen aligned, then generate a PoseToWorld matrix that billboards the bone
				ScreenAlignBone( &pPoseToWorld[i], pCurBone, vecViewOrigin, pBoneToWorld[i] );
			} 	
#endif
}

//-----------------------------------------------------------------------------
// Helper to determine which material type to use depending on what strip
// header flags are set.
//-----------------------------------------------------------------------------
MaterialPrimitiveType_t GetPrimitiveTypeForStripHeaderFlags( unsigned char Flags )
{
	if ( Flags & OptimizedModel::STRIP_IS_QUADLIST_EXTRA )
		return MATERIAL_SUBD_QUADS_EXTRA;
	else if( Flags & OptimizedModel::STRIP_IS_QUADLIST_REG )
		return MATERIAL_SUBD_QUADS_REG;
	return MATERIAL_TRIANGLES;
}