/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code 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; either version 2 of the License,
or (at your option) any later version.

Quake III Arena source code 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 for more details.

You should have received a copy of the GNU General Public License
along with Quake III Arena source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/

/* This file is only compiled for PowerPC builds with Altivec support.
   Altivec intrinsics need to be in a separate file, so GCC's -maltivec
   command line can enable them, but give us the option to _not_ use that
   on other files, where the compiler might then generate Altivec
   instructions for normal floating point, crashing on G3 (etc) processors. */

#include "tr_local.h" 

#if idppc_altivec

#if !defined(__APPLE__)
#include <altivec.h>
#endif

void ProjectDlightTexture_altivec( void ) {
	int		i, l;
	vec_t	origin0, origin1, origin2;
	float   texCoords0, texCoords1;
	vector float floatColorVec0, floatColorVec1;
	vector float modulateVec, colorVec, zero;
	vector short colorShort;
	vector signed int colorInt;
	vector unsigned char floatColorVecPerm, modulatePerm, colorChar;
	vector unsigned char vSel = VECCONST_UINT8(0x00, 0x00, 0x00, 0xff,
                                               0x00, 0x00, 0x00, 0xff,
                                               0x00, 0x00, 0x00, 0xff,
                                               0x00, 0x00, 0x00, 0xff);
	float	*texCoords;
	byte	*colors;
	byte	clipBits[SHADER_MAX_VERTEXES];
	float	texCoordsArray[SHADER_MAX_VERTEXES][2];
	byte	colorArray[SHADER_MAX_VERTEXES][4];
	glIndex_t	hitIndexes[SHADER_MAX_INDEXES];
	int		numIndexes;
	float	scale;
	float	radius;
	vec3_t	floatColor;
	float	modulate = 0.0f;

	if ( !backEnd.refdef.num_dlights ) {
		return;
	}

	// There has to be a better way to do this so that floatColor
	// and/or modulate are already 16-byte aligned.
	floatColorVecPerm = vec_lvsl(0,(float *)floatColor);
	modulatePerm = vec_lvsl(0,(float *)&modulate);
	modulatePerm = (vector unsigned char)vec_splat((vector unsigned int)modulatePerm,0);
	zero = (vector float)vec_splat_s8(0);

	for ( l = 0 ; l < backEnd.refdef.num_dlights ; l++ ) {
		dlight_t	*dl;

		if ( !( tess.dlightBits & ( 1 << l ) ) ) {
			continue;	// this surface definitely doesn't have any of this light
		}
		texCoords = texCoordsArray[0];
		colors = colorArray[0];

		dl = &backEnd.refdef.dlights[l];
		origin0 = dl->transformed[0];
		origin1 = dl->transformed[1];
		origin2 = dl->transformed[2];
		radius = dl->radius;
		scale = 1.0f / radius;

		if(r_greyscale->integer)
		{
			float luminance;
			
			luminance = LUMA(dl->color[0], dl->color[1], dl->color[2]) * 255.0f;
			floatColor[0] = floatColor[1] = floatColor[2] = luminance;
		}
		else if(r_greyscale->value)
		{
			float luminance;
			
			luminance = LUMA(dl->color[0], dl->color[1], dl->color[2]) * 255.0f;
			floatColor[0] = LERP(dl->color[0] * 255.0f, luminance, r_greyscale->value);
			floatColor[1] = LERP(dl->color[1] * 255.0f, luminance, r_greyscale->value);
			floatColor[2] = LERP(dl->color[2] * 255.0f, luminance, r_greyscale->value);
		}
		else
		{
			floatColor[0] = dl->color[0] * 255.0f;
			floatColor[1] = dl->color[1] * 255.0f;
			floatColor[2] = dl->color[2] * 255.0f;
		}
		floatColorVec0 = vec_ld(0, floatColor);
		floatColorVec1 = vec_ld(11, floatColor);
		floatColorVec0 = vec_perm(floatColorVec0,floatColorVec0,floatColorVecPerm);
		for ( i = 0 ; i < tess.numVertexes ; i++, texCoords += 2, colors += 4 ) {
			int		clip = 0;
			vec_t dist0, dist1, dist2;
			
			dist0 = origin0 - tess.xyz[i][0];
			dist1 = origin1 - tess.xyz[i][1];
			dist2 = origin2 - tess.xyz[i][2];

			backEnd.pc.c_dlightVertexes++;

			texCoords0 = 0.5f + dist0 * scale;
			texCoords1 = 0.5f + dist1 * scale;

			if( !r_dlightBacks->integer &&
					// dist . tess.normal[i]
					( dist0 * tess.normal[i][0] +
					dist1 * tess.normal[i][1] +
					dist2 * tess.normal[i][2] ) < 0.0f ) {
				clip = 63;
			} else {
				if ( texCoords0 < 0.0f ) {
					clip |= 1;
				} else if ( texCoords0 > 1.0f ) {
					clip |= 2;
				}
				if ( texCoords1 < 0.0f ) {
					clip |= 4;
				} else if ( texCoords1 > 1.0f ) {
					clip |= 8;
				}
				texCoords[0] = texCoords0;
				texCoords[1] = texCoords1;

				// modulate the strength based on the height and color
				if ( dist2 > radius ) {
					clip |= 16;
					modulate = 0.0f;
				} else if ( dist2 < -radius ) {
					clip |= 32;
					modulate = 0.0f;
				} else {
					dist2 = Q_fabs(dist2);
					if ( dist2 < radius * 0.5f ) {
						modulate = 1.0f;
					} else {
						modulate = 2.0f * (radius - dist2) * scale;
					}
				}
			}
			clipBits[i] = clip;

			modulateVec = vec_ld(0,(float *)&modulate);
			modulateVec = vec_perm(modulateVec,modulateVec,modulatePerm);
			colorVec = vec_madd(floatColorVec0,modulateVec,zero);
			colorInt = vec_cts(colorVec,0);	// RGBx
			colorShort = vec_pack(colorInt,colorInt);		// RGBxRGBx
			colorChar = vec_packsu(colorShort,colorShort);	// RGBxRGBxRGBxRGBx
			colorChar = vec_sel(colorChar,vSel,vSel);		// RGBARGBARGBARGBA replace alpha with 255
			vec_ste((vector unsigned int)colorChar,0,(unsigned int *)colors);	// store color
		}

		// build a list of triangles that need light
		numIndexes = 0;
		for ( i = 0 ; i < tess.numIndexes ; i += 3 ) {
			int		a, b, c;

			a = tess.indexes[i];
			b = tess.indexes[i+1];
			c = tess.indexes[i+2];
			if ( clipBits[a] & clipBits[b] & clipBits[c] ) {
				continue;	// not lighted
			}
			hitIndexes[numIndexes] = a;
			hitIndexes[numIndexes+1] = b;
			hitIndexes[numIndexes+2] = c;
			numIndexes += 3;
		}

		if ( !numIndexes ) {
			continue;
		}

		qglEnableClientState( GL_TEXTURE_COORD_ARRAY );
		qglTexCoordPointer( 2, GL_FLOAT, 0, texCoordsArray[0] );

		qglEnableClientState( GL_COLOR_ARRAY );
		qglColorPointer( 4, GL_UNSIGNED_BYTE, 0, colorArray );

		GL_Bind( tr.dlightImage );
		// include GLS_DEPTHFUNC_EQUAL so alpha tested surfaces don't add light
		// where they aren't rendered
		if ( dl->additive ) {
			GL_State( GLS_SRCBLEND_ONE | GLS_DSTBLEND_ONE | GLS_DEPTHFUNC_EQUAL );
		}
		else {
			GL_State( GLS_SRCBLEND_DST_COLOR | GLS_DSTBLEND_ONE | GLS_DEPTHFUNC_EQUAL );
		}
		R_DrawElements( numIndexes, hitIndexes );
		backEnd.pc.c_totalIndexes += numIndexes;
		backEnd.pc.c_dlightIndexes += numIndexes;
	}
}

void RB_CalcDiffuseColor_altivec( unsigned char *colors )
{
	int				i;
	float			*v, *normal;
	trRefEntity_t	*ent;
	int				ambientLightInt;
	vec3_t			lightDir;
	int				numVertexes;
	vector unsigned char vSel = VECCONST_UINT8(0x00, 0x00, 0x00, 0xff,
                                               0x00, 0x00, 0x00, 0xff,
                                               0x00, 0x00, 0x00, 0xff,
                                               0x00, 0x00, 0x00, 0xff);
	vector float ambientLightVec;
	vector float directedLightVec;
	vector float lightDirVec;
	vector float normalVec0, normalVec1;
	vector float incomingVec0, incomingVec1, incomingVec2;
	vector float zero, jVec;
	vector signed int jVecInt;
	vector signed short jVecShort;
	vector unsigned char jVecChar, normalPerm;
	ent = backEnd.currentEntity;
	ambientLightInt = ent->ambientLightInt;
	// A lot of this could be simplified if we made sure
	// entities light info was 16-byte aligned.
	jVecChar = vec_lvsl(0, ent->ambientLight);
	ambientLightVec = vec_ld(0, (vector float *)ent->ambientLight);
	jVec = vec_ld(11, (vector float *)ent->ambientLight);
	ambientLightVec = vec_perm(ambientLightVec,jVec,jVecChar);

	jVecChar = vec_lvsl(0, ent->directedLight);
	directedLightVec = vec_ld(0,(vector float *)ent->directedLight);
	jVec = vec_ld(11,(vector float *)ent->directedLight);
	directedLightVec = vec_perm(directedLightVec,jVec,jVecChar);	 

	jVecChar = vec_lvsl(0, ent->lightDir);
	lightDirVec = vec_ld(0,(vector float *)ent->lightDir);
	jVec = vec_ld(11,(vector float *)ent->lightDir);
	lightDirVec = vec_perm(lightDirVec,jVec,jVecChar);	 

	zero = (vector float)vec_splat_s8(0);
	VectorCopy( ent->lightDir, lightDir );

	v = tess.xyz[0];
	normal = tess.normal[0];

	normalPerm = vec_lvsl(0,normal);
	numVertexes = tess.numVertexes;
	for (i = 0 ; i < numVertexes ; i++, v += 4, normal += 4) {
		normalVec0 = vec_ld(0,(vector float *)normal);
		normalVec1 = vec_ld(11,(vector float *)normal);
		normalVec0 = vec_perm(normalVec0,normalVec1,normalPerm);
		incomingVec0 = vec_madd(normalVec0, lightDirVec, zero);
		incomingVec1 = vec_sld(incomingVec0,incomingVec0,4);
		incomingVec2 = vec_add(incomingVec0,incomingVec1);
		incomingVec1 = vec_sld(incomingVec1,incomingVec1,4);
		incomingVec2 = vec_add(incomingVec2,incomingVec1);
		incomingVec0 = vec_splat(incomingVec2,0);
		incomingVec0 = vec_max(incomingVec0,zero);
		normalPerm = vec_lvsl(12,normal);
		jVec = vec_madd(incomingVec0, directedLightVec, ambientLightVec);
		jVecInt = vec_cts(jVec,0);	// RGBx
		jVecShort = vec_pack(jVecInt,jVecInt);		// RGBxRGBx
		jVecChar = vec_packsu(jVecShort,jVecShort);	// RGBxRGBxRGBxRGBx
		jVecChar = vec_sel(jVecChar,vSel,vSel);		// RGBARGBARGBARGBA replace alpha with 255
		vec_ste((vector unsigned int)jVecChar,0,(unsigned int *)&colors[i*4]);	// store color
	}
}

void LerpMeshVertexes_altivec(md3Surface_t *surf, float backlerp)
{
	short	*oldXyz, *newXyz, *oldNormals, *newNormals;
	float	*outXyz, *outNormal;
	float	oldXyzScale QALIGN(16);
	float   newXyzScale QALIGN(16);
	float	oldNormalScale QALIGN(16);
	float newNormalScale QALIGN(16);
	int		vertNum;
	unsigned lat, lng;
	int		numVerts;

	outXyz = tess.xyz[tess.numVertexes];
	outNormal = tess.normal[tess.numVertexes];

	newXyz = (short *)((byte *)surf + surf->ofsXyzNormals)
		+ (backEnd.currentEntity->e.frame * surf->numVerts * 4);
	newNormals = newXyz + 3;

	newXyzScale = MD3_XYZ_SCALE * (1.0 - backlerp);
	newNormalScale = 1.0 - backlerp;

	numVerts = surf->numVerts;

	if ( backlerp == 0 ) {
		vector signed short newNormalsVec0;
		vector signed short newNormalsVec1;
		vector signed int newNormalsIntVec;
		vector float newNormalsFloatVec;
		vector float newXyzScaleVec;
		vector unsigned char newNormalsLoadPermute;
		vector unsigned char newNormalsStorePermute;
		vector float zero;
		
		newNormalsStorePermute = vec_lvsl(0,(float *)&newXyzScaleVec);
		newXyzScaleVec = *(vector float *)&newXyzScale;
		newXyzScaleVec = vec_perm(newXyzScaleVec,newXyzScaleVec,newNormalsStorePermute);
		newXyzScaleVec = vec_splat(newXyzScaleVec,0);		
		newNormalsLoadPermute = vec_lvsl(0,newXyz);
		newNormalsStorePermute = vec_lvsr(0,outXyz);
		zero = (vector float)vec_splat_s8(0);
		//
		// just copy the vertexes
		//
		for (vertNum=0 ; vertNum < numVerts ; vertNum++,
			newXyz += 4, newNormals += 4,
			outXyz += 4, outNormal += 4) 
		{
			newNormalsLoadPermute = vec_lvsl(0,newXyz);
			newNormalsStorePermute = vec_lvsr(0,outXyz);
			newNormalsVec0 = vec_ld(0,newXyz);
			newNormalsVec1 = vec_ld(16,newXyz);
			newNormalsVec0 = vec_perm(newNormalsVec0,newNormalsVec1,newNormalsLoadPermute);
			newNormalsIntVec = vec_unpackh(newNormalsVec0);
			newNormalsFloatVec = vec_ctf(newNormalsIntVec,0);
			newNormalsFloatVec = vec_madd(newNormalsFloatVec,newXyzScaleVec,zero);
			newNormalsFloatVec = vec_perm(newNormalsFloatVec,newNormalsFloatVec,newNormalsStorePermute);
			//outXyz[0] = newXyz[0] * newXyzScale;
			//outXyz[1] = newXyz[1] * newXyzScale;
			//outXyz[2] = newXyz[2] * newXyzScale;

			lat = ( newNormals[0] >> 8 ) & 0xff;
			lng = ( newNormals[0] & 0xff );
			lat *= (FUNCTABLE_SIZE/256);
			lng *= (FUNCTABLE_SIZE/256);

			// decode X as cos( lat ) * sin( long )
			// decode Y as sin( lat ) * sin( long )
			// decode Z as cos( long )

			outNormal[0] = tr.sinTable[(lat+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK] * tr.sinTable[lng];
			outNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
			outNormal[2] = tr.sinTable[(lng+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK];

			vec_ste(newNormalsFloatVec,0,outXyz);
			vec_ste(newNormalsFloatVec,4,outXyz);
			vec_ste(newNormalsFloatVec,8,outXyz);
		}
	} else {
		//
		// interpolate and copy the vertex and normal
		//
		oldXyz = (short *)((byte *)surf + surf->ofsXyzNormals)
			+ (backEnd.currentEntity->e.oldframe * surf->numVerts * 4);
		oldNormals = oldXyz + 3;

		oldXyzScale = MD3_XYZ_SCALE * backlerp;
		oldNormalScale = backlerp;

		for (vertNum=0 ; vertNum < numVerts ; vertNum++,
			oldXyz += 4, newXyz += 4, oldNormals += 4, newNormals += 4,
			outXyz += 4, outNormal += 4) 
		{
			vec3_t uncompressedOldNormal, uncompressedNewNormal;

			// interpolate the xyz
			outXyz[0] = oldXyz[0] * oldXyzScale + newXyz[0] * newXyzScale;
			outXyz[1] = oldXyz[1] * oldXyzScale + newXyz[1] * newXyzScale;
			outXyz[2] = oldXyz[2] * oldXyzScale + newXyz[2] * newXyzScale;

			// FIXME: interpolate lat/long instead?
			lat = ( newNormals[0] >> 8 ) & 0xff;
			lng = ( newNormals[0] & 0xff );
			lat *= 4;
			lng *= 4;
			uncompressedNewNormal[0] = tr.sinTable[(lat+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK] * tr.sinTable[lng];
			uncompressedNewNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
			uncompressedNewNormal[2] = tr.sinTable[(lng+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK];

			lat = ( oldNormals[0] >> 8 ) & 0xff;
			lng = ( oldNormals[0] & 0xff );
			lat *= 4;
			lng *= 4;

			uncompressedOldNormal[0] = tr.sinTable[(lat+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK] * tr.sinTable[lng];
			uncompressedOldNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
			uncompressedOldNormal[2] = tr.sinTable[(lng+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK];

			outNormal[0] = uncompressedOldNormal[0] * oldNormalScale + uncompressedNewNormal[0] * newNormalScale;
			outNormal[1] = uncompressedOldNormal[1] * oldNormalScale + uncompressedNewNormal[1] * newNormalScale;
			outNormal[2] = uncompressedOldNormal[2] * oldNormalScale + uncompressedNewNormal[2] * newNormalScale;

//			VectorNormalize (outNormal);
		}
    	VectorArrayNormalize((vec4_t *)tess.normal[tess.numVertexes], numVerts);
   	}
}

#endif