/*
Copyright (C) 1999-2006 Id Software, Inc. and contributors.
For a list of contributors, see the accompanying CONTRIBUTORS file.

This file is part of GtkRadiant.

GtkRadiant 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.

GtkRadiant 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 GtkRadiant; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

#include "brush_primit.h"

#include "debugging/debugging.h"

#include "itexdef.h"
#include "itextures.h"

#include <algorithm>

#include "stringio.h"
#include "texturelib.h"
#include "math/matrix.h"
#include "math/plane.h"
#include "math/aabb.h"

#include "winding.h"
#include "preferences.h"


/*!
\brief Construct a transform from XYZ space to ST space (3d to 2d).
This will be one of three axis-aligned spaces, depending on the surface normal.
NOTE: could also be done by swapping values.
*/
void Normal_GetTransform(const Vector3& normal, Matrix4& transform)
{
  switch (projectionaxis_for_normal(normal))
  {
  case eProjectionAxisZ:
    transform[0]  =  1;
    transform[1]  =  0;
    transform[2]  =  0;
    
    transform[4]  =  0;
    transform[5]  =  1;
    transform[6]  =  0;
    
    transform[8]  =  0;
    transform[9]  =  0;
    transform[10] =  1;
    break;
  case eProjectionAxisY:
    transform[0]  =  1;
    transform[1]  =  0;
    transform[2]  =  0;
    
    transform[4]  =  0;
    transform[5]  =  0;
    transform[6]  = -1;
    
    transform[8]  =  0;
    transform[9]  =  1;
    transform[10] =  0;
    break;
  case eProjectionAxisX:
    transform[0]  =  0;
    transform[1]  =  0;
    transform[2]  =  1;
    
    transform[4]  =  1;
    transform[5]  =  0;
    transform[6]  =  0;
    
    transform[8]  =  0;
    transform[9]  =  1;
    transform[10] =  0;
    break;
  }
  transform[3] = transform[7] = transform[11] = transform[12] = transform[13] = transform[14] = 0;
  transform[15] = 1;
}

/*!
\brief Construct a transform in ST space from the texdef.
Transforms constructed from quake's texdef format are (-shift)*(1/scale)*(-rotate) with x translation sign flipped.
This would really make more sense if it was inverseof(shift*rotate*scale).. oh well.
*/
inline void Texdef_toTransform(const texdef_t& texdef, float width, float height, Matrix4& transform)
{
  double inverse_scale[2];
  
  // transform to texdef shift/scale/rotate
  inverse_scale[0] = 1 / (texdef.scale[0] * width);
  inverse_scale[1] = 1 / (texdef.scale[1] * -height);
  transform[12] = texdef.shift[0] / width;
  transform[13] = -texdef.shift[1] / -height;
  double c = cos(degrees_to_radians(-texdef.rotate));
  double s = sin(degrees_to_radians(-texdef.rotate));
  transform[0] = static_cast<float>(c * inverse_scale[0]);
  transform[1] = static_cast<float>(s * inverse_scale[1]);
  transform[4] = static_cast<float>(-s * inverse_scale[0]);
  transform[5] = static_cast<float>(c * inverse_scale[1]);
  transform[2] = transform[3] = transform[6] = transform[7] = transform[8] = transform[9] = transform[11] = transform[14] = 0;
  transform[10] = transform[15] = 1;
}

inline void BPTexdef_toTransform(const brushprimit_texdef_t& bp_texdef, Matrix4& transform)
{
  transform = g_matrix4_identity;
  transform.xx() = bp_texdef.coords[0][0];
  transform.yx() = bp_texdef.coords[0][1];
  transform.tx() = bp_texdef.coords[0][2];
  transform.xy() = bp_texdef.coords[1][0];
  transform.yy() = bp_texdef.coords[1][1];
  transform.ty() = bp_texdef.coords[1][2];
}

inline void Texdef_toTransform(const TextureProjection& projection, float width, float height, Matrix4& transform)
{
  if(g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
  {
    BPTexdef_toTransform(projection.m_brushprimit_texdef, transform);
  }
  else
  {
    Texdef_toTransform(projection.m_texdef, width, height, transform);
  }
}

// handles degenerate cases, just in case library atan2 doesn't
inline double arctangent_yx(double y, double x)
{
  if(fabs(x) > 1.0E-6)
  {
    return atan2(y, x);
  }
  else if(y > 0)
  {
		return c_half_pi;
  }
  else
  {
		return -c_half_pi;
  }
}

inline void Texdef_fromTransform(texdef_t& texdef, float width, float height, const Matrix4& transform)
{
  texdef.scale[0] = static_cast<float>((1.0 / vector2_length(Vector2(transform[0], transform[4]))) / width);
  texdef.scale[1] = static_cast<float>((1.0 / vector2_length(Vector2(transform[1], transform[5]))) / height);

  texdef.rotate = static_cast<float>(-radians_to_degrees(arctangent_yx(-transform[4], transform[0])));

  if(texdef.rotate == -180.0f)
  {
    texdef.rotate = 180.0f;
  }

  texdef.shift[0] = transform[12] * width;
  texdef.shift[1] = transform[13] * height;

  // If the 2d cross-product of the x and y axes is positive, one of the axes has a negative scale.
  if(vector2_cross(Vector2(transform[0], transform[4]), Vector2(transform[1], transform[5])) > 0)
  {
    if(texdef.rotate >= 180.0f)
    {
      texdef.rotate -= 180.0f;
      texdef.scale[0] = -texdef.scale[0];
    }
    else
    {
      texdef.scale[1] = -texdef.scale[1];
    }
  }
  //globalOutputStream() << "fromTransform: " << texdef.shift[0] << " " << texdef.shift[1] << " " << texdef.scale[0] << " " << texdef.scale[1] << " " << texdef.rotate << "\n";
}

inline void BPTexdef_fromTransform(brushprimit_texdef_t& bp_texdef, const Matrix4& transform)
{
  bp_texdef.coords[0][0] = transform.xx();
  bp_texdef.coords[0][1] = transform.yx();
  bp_texdef.coords[0][2] = transform.tx();
  bp_texdef.coords[1][0] = transform.xy();
  bp_texdef.coords[1][1] = transform.yy();
  bp_texdef.coords[1][2] = transform.ty();
}

inline void Texdef_fromTransform(TextureProjection& projection, float width, float height, const Matrix4& transform)
{
  ASSERT_MESSAGE((transform[0] != 0 || transform[4] != 0)
    && (transform[1] != 0 || transform[5] != 0), "invalid texture matrix");

  if(g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
  {
    BPTexdef_fromTransform(projection.m_brushprimit_texdef, transform);
  }
  else
  {
    Texdef_fromTransform(projection.m_texdef, width, height, transform);
  }
}

inline void Texdef_normalise(texdef_t& texdef, float width, float height)
{
  // it may be useful to also normalise the rotation here, if this function is used elsewhere.
  texdef.shift[0] = float_mod(texdef.shift[0], width);
  texdef.shift[1] = float_mod(texdef.shift[1], height);
  //globalOutputStream() << "normalise: " << texdef.shift[0] << " " << texdef.shift[1] << " " << texdef.scale[0] << " " << texdef.scale[1] << " " << texdef.rotate << "\n";
}

inline void BPTexdef_normalise(brushprimit_texdef_t& bp_texdef, float width, float height)
{
  bp_texdef.coords[0][2] = float_mod(bp_texdef.coords[0][2], width);
  bp_texdef.coords[1][2] = float_mod(bp_texdef.coords[1][2], height);
}

/// \brief Normalise \p projection for a given texture \p width and \p height.
///
/// All texture-projection translation (shift) values are congruent modulo the dimensions of the texture.
/// This function normalises shift values to the smallest positive congruent values.
void Texdef_normalise(TextureProjection& projection, float width, float height)
{
  if(g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
  {
    BPTexdef_normalise(projection.m_brushprimit_texdef, width, height);
  }
  else
  {
    Texdef_normalise(projection.m_texdef, width, height);
  }
}

void ComputeAxisBase(const Vector3& normal, Vector3& texS, Vector3& texT);

inline void DebugAxisBase(const Vector3& normal)
{
  Vector3 x, y;
  ComputeAxisBase(normal, x, y);
  globalOutputStream() << "BP debug: " << x << y << normal << "\n";
}

void Texdef_basisForNormal(const TextureProjection& projection, const Vector3& normal, Matrix4& basis)
{
  if(g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
  {
    basis = g_matrix4_identity;
    ComputeAxisBase(normal, vector4_to_vector3(basis.x()), vector4_to_vector3(basis.y()));
    vector4_to_vector3(basis.z()) = normal;
    matrix4_transpose(basis);
    //DebugAxisBase(normal);
  }
  else if(g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_HALFLIFE)
  {
    basis = g_matrix4_identity;
    vector4_to_vector3(basis.x()) = projection.m_basis_s;
    vector4_to_vector3(basis.y()) = vector3_negated(projection.m_basis_t);
    vector4_to_vector3(basis.z()) = vector3_normalised(vector3_cross(vector4_to_vector3(basis.x()), vector4_to_vector3(basis.y())));
    matrix4_multiply_by_matrix4(basis, matrix4_rotation_for_z_degrees(-projection.m_texdef.rotate));
    //globalOutputStream() << "debug: " << projection.m_basis_s << projection.m_basis_t << normal << "\n";
    matrix4_transpose(basis);
  }
  else
  {
    Normal_GetTransform(normal, basis);
  }
}

void Texdef_EmitTextureCoordinates(const TextureProjection& projection, std::size_t width, std::size_t height, Winding& w, const Vector3& normal, const Matrix4& localToWorld)
{
  if(w.numpoints < 3)
  {
    return;
  }
  //globalOutputStream() << "normal: " << normal << "\n";

  Matrix4 local2tex;
  Texdef_toTransform(projection, (float)width, (float)height, local2tex);
  //globalOutputStream() << "texdef: " << static_cast<const Vector3&>(local2tex.x()) << static_cast<const Vector3&>(local2tex.y()) << "\n";

#if 0
  {
    TextureProjection tmp;
    Texdef_fromTransform(tmp, (float)width, (float)height, local2tex);
    Matrix4 tmpTransform;
    Texdef_toTransform(tmp, (float)width, (float)height, tmpTransform);
    ASSERT_MESSAGE(matrix4_equal_epsilon(local2tex, tmpTransform, 0.0001f), "bleh");
  }
#endif
  
  {
    Matrix4 xyz2st; 
    // we don't care if it's not normalised...
    Texdef_basisForNormal(projection, matrix4_transformed_direction(localToWorld, normal), xyz2st);
    //globalOutputStream() << "basis: " << static_cast<const Vector3&>(xyz2st.x()) << static_cast<const Vector3&>(xyz2st.y()) << static_cast<const Vector3&>(xyz2st.z()) << "\n";
    matrix4_multiply_by_matrix4(local2tex, xyz2st);
  }

  Vector3 tangent(vector3_normalised(vector4_to_vector3(matrix4_transposed(local2tex).x())));
  Vector3 bitangent(vector3_normalised(vector4_to_vector3(matrix4_transposed(local2tex).y())));
  
  matrix4_multiply_by_matrix4(local2tex, localToWorld);

  for(Winding::iterator i = w.begin(); i != w.end(); ++i)
  {
    Vector3 texcoord = matrix4_transformed_point(local2tex, (*i).vertex);
    (*i).texcoord[0] = texcoord[0];
    (*i).texcoord[1] = texcoord[1];

    (*i).tangent = tangent;
    (*i).bitangent = bitangent;
  }
}

/*!
\brief Provides the axis-base of the texture ST space for this normal,
as they had been transformed to world XYZ space.
*/
void TextureAxisFromNormal(const Vector3& normal, Vector3& s, Vector3& t)
{
  switch (projectionaxis_for_normal(normal))
  {
  case eProjectionAxisZ:
    s[0]  =  1;
    s[1]  =  0;
    s[2]  =  0;
    
    t[0]  =  0;
    t[1]  = -1;
    t[2]  =  0;

    break;
  case eProjectionAxisY:
    s[0]  =  1;
    s[1]  =  0;
    s[2]  =  0;
    
    t[0]  =  0;
    t[1]  =  0;
    t[2]  = -1;

    break;
  case eProjectionAxisX:
    s[0]  =  0;
    s[1]  =  1;
    s[2]  =  0;
    
    t[0]  =  0;
    t[1]  =  0;
    t[2]  = -1;

    break;
  }
}

void Texdef_Assign(texdef_t& td, const texdef_t& other)
{
  td = other;
}

void Texdef_Shift(texdef_t& td, float s, float t)
{
	td.shift[0] += s;
	td.shift[1] += t;
}

void Texdef_Scale(texdef_t& td, float s, float t)
{
	td.scale[0] += s;
	td.scale[1] += t;
}

void Texdef_Rotate(texdef_t& td, float angle)
{
	td.rotate += angle;
	td.rotate = static_cast<float>(float_to_integer(td.rotate) % 360);
}

// NOTE: added these from Ritual's Q3Radiant
void ClearBounds(Vector3& mins, Vector3& maxs)
{
	mins[0] = mins[1] = mins[2] = 99999;
	maxs[0] = maxs[1] = maxs[2] = -99999;
}

void AddPointToBounds(const Vector3& v, Vector3& mins, Vector3& maxs)
{
	int		i;
	float	val;
	
	for (i=0 ; i<3 ; i++)
	{
		val = v[i];
		if (val < mins[i])
			mins[i] = val;
		if (val > maxs[i])
			maxs[i] = val;
	}
}

template<typename Element>
inline BasicVector3<Element> vector3_inverse(const BasicVector3<Element>& self)
{
  return BasicVector3<Element>(
    Element(1.0 / self.x()),
    Element(1.0 / self.y()),
    Element(1.0 / self.z())
  );
}

// low level functions .. put in mathlib?
#define BPMatCopy(a,b) {b[0][0] = a[0][0]; b[0][1] = a[0][1]; b[0][2] = a[0][2]; b[1][0] = a[1][0]; b[1][1] = a[1][1]; b[1][2] = a[1][2];}
// apply a scale transformation to the BP matrix
#define BPMatScale(m,sS,sT) {m[0][0]*=sS; m[1][0]*=sS; m[0][1]*=sT; m[1][1]*=sT;}
// apply a translation transformation to a BP matrix
#define BPMatTranslate(m,s,t) {m[0][2] += m[0][0]*s + m[0][1]*t; m[1][2] += m[1][0]*s+m[1][1]*t;}
// 2D homogeneous matrix product C = A*B
void BPMatMul(float A[2][3], float B[2][3], float C[2][3]);
// apply a rotation (degrees)
void BPMatRotate(float A[2][3], float theta);
#ifdef _DEBUG
void BPMatDump(float A[2][3]);
#endif

#ifdef _DEBUG
//#define DBG_BP
#endif


bp_globals_t g_bp_globals;
float g_texdef_default_scale;

// compute a determinant using Sarrus rule
//++timo "inline" this with a macro
// NOTE : the three vectors are understood as columns of the matrix
inline float SarrusDet(const Vector3& a, const Vector3& b, const Vector3& c)
{
	return a[0]*b[1]*c[2]+b[0]*c[1]*a[2]+c[0]*a[1]*b[2]
		-c[0]*b[1]*a[2]-a[1]*b[0]*c[2]-a[0]*b[2]*c[1];
}

// in many case we know three points A,B,C in two axis base B1 and B2
// and we want the matrix M so that A(B1) = T * A(B2)
// NOTE: 2D homogeneous space stuff
// NOTE: we don't do any check to see if there's a solution or we have a particular case .. need to make sure before calling
// NOTE: the third coord of the A,B,C point is ignored
// NOTE: see the commented out section to fill M and D
//++timo TODO: update the other members to use this when possible
void MatrixForPoints( Vector3 M[3], Vector3 D[2], brushprimit_texdef_t *T )
{
//	Vector3 M[3]; // columns of the matrix .. easier that way (the indexing is not standard! it's column-line .. later computations are easier that way)
	float det;
//	Vector3 D[2];
	M[2][0]=1.0f; M[2][1]=1.0f; M[2][2]=1.0f;
#if 0
	// fill the data vectors
	M[0][0]=A2[0]; M[0][1]=B2[0]; M[0][2]=C2[0];
	M[1][0]=A2[1]; M[1][1]=B2[1]; M[1][2]=C2[1];
	M[2][0]=1.0f; M[2][1]=1.0f; M[2][2]=1.0f;
	D[0][0]=A1[0];
	D[0][1]=B1[0];
	D[0][2]=C1[0];
	D[1][0]=A1[1];
	D[1][1]=B1[1];
	D[1][2]=C1[1];
#endif
	// solve
	det = SarrusDet( M[0], M[1], M[2] );
	T->coords[0][0] = SarrusDet( D[0], M[1], M[2] ) / det;
	T->coords[0][1] = SarrusDet( M[0], D[0], M[2] ) / det;
	T->coords[0][2] = SarrusDet( M[0], M[1], D[0] ) / det;
	T->coords[1][0] = SarrusDet( D[1], M[1], M[2] ) / det;
	T->coords[1][1] = SarrusDet( M[0], D[1], M[2] ) / det;
	T->coords[1][2] = SarrusDet( M[0], M[1], D[1] ) / det;
}

//++timo replace everywhere texX by texS etc. ( ----> and in q3map !) 
// NOTE : ComputeAxisBase here and in q3map code must always BE THE SAME !
// WARNING : special case behaviour of atan2(y,x) <-> atan(y/x) might not be the same everywhere when x == 0
// rotation by (0,RotY,RotZ) assigns X to normal
void ComputeAxisBase(const Vector3& normal, Vector3& texS, Vector3& texT)
{
#if 1
  const Vector3 up(0, 0, 1);
  const Vector3 down(0, 0, -1);

  if(vector3_equal_epsilon(normal, up, float(1e-6)))
  {
    texS = Vector3(0, 1, 0);
    texT = Vector3(1, 0, 0);
  }
  else if(vector3_equal_epsilon(normal, down, float(1e-6)))
  {
    texS = Vector3(0, 1, 0);
    texT = Vector3(-1, 0, 0);
  }
  else
  {
    texS = vector3_normalised(vector3_cross(normal, up));
    texT = vector3_normalised(vector3_cross(normal, texS));
    vector3_negate(texS);
  }

#else
	float RotY,RotZ;
	// do some cleaning
  /*
	if (fabs(normal[0])<1e-6)
		normal[0]=0.0f;
	if (fabs(normal[1])<1e-6)
		normal[1]=0.0f;
	if (fabs(normal[2])<1e-6)
		normal[2]=0.0f;
    */
	RotY=-atan2(normal[2],sqrt(normal[1]*normal[1]+normal[0]*normal[0]));
	RotZ=atan2(normal[1],normal[0]);
	// rotate (0,1,0) and (0,0,1) to compute texS and texT
	texS[0]=-sin(RotZ);
	texS[1]=cos(RotZ);
	texS[2]=0;
	// the texT vector is along -Z ( T texture coorinates axis )
	texT[0]=-sin(RotY)*cos(RotZ);
	texT[1]=-sin(RotY)*sin(RotZ);
	texT[2]=-cos(RotY);
#endif
}

#if 0 // texdef conversion
void FaceToBrushPrimitFace(face_t *f)
{
	Vector3 texX,texY;
	Vector3 proj;
	// ST of (0,0) (1,0) (0,1)
	float ST[3][5]; // [ point index ] [ xyz ST ]
	//++timo not used as long as brushprimit_texdef and texdef are static
/*	f->brushprimit_texdef.contents=f->texdef.contents;
	f->brushprimit_texdef.flags=f->texdef.flags;
	f->brushprimit_texdef.value=f->texdef.value;
	strcpy(f->brushprimit_texdef.name,f->texdef.name); */
#ifdef DBG_BP
	if ( f->plane.normal[0]==0.0f && f->plane.normal[1]==0.0f && f->plane.normal[2]==0.0f )
	{
		globalOutputStream() << "Warning : f->plane.normal is (0,0,0) in FaceToBrushPrimitFace\n";
	}
	// check d_texture
	if (!f->d_texture)
	{
		globalOutputStream() << "Warning : f.d_texture is 0 in FaceToBrushPrimitFace\n";
		return;
	}
#endif
	// compute axis base
	ComputeAxisBase(f->plane.normal,texX,texY);
	// compute projection vector
	VectorCopy(f->plane.normal,proj);
	VectorScale(proj,f->plane.dist,proj);
	// (0,0) in plane axis base is (0,0,0) in world coordinates + projection on the affine plane
	// (1,0) in plane axis base is texX in world coordinates + projection on the affine plane
	// (0,1) in plane axis base is texY in world coordinates + projection on the affine plane
	// use old texture code to compute the ST coords of these points
	VectorCopy(proj,ST[0]);
	EmitTextureCoordinates(ST[0], f->pShader->getTexture(), f);
	VectorCopy(texX,ST[1]);
	VectorAdd(ST[1],proj,ST[1]);
	EmitTextureCoordinates(ST[1], f->pShader->getTexture(), f);
	VectorCopy(texY,ST[2]);
	VectorAdd(ST[2],proj,ST[2]);
	EmitTextureCoordinates(ST[2], f->pShader->getTexture(), f);
	// compute texture matrix
	f->brushprimit_texdef.coords[0][2]=ST[0][3];
	f->brushprimit_texdef.coords[1][2]=ST[0][4];
	f->brushprimit_texdef.coords[0][0]=ST[1][3]-f->brushprimit_texdef.coords[0][2];
	f->brushprimit_texdef.coords[1][0]=ST[1][4]-f->brushprimit_texdef.coords[1][2];
	f->brushprimit_texdef.coords[0][1]=ST[2][3]-f->brushprimit_texdef.coords[0][2];
	f->brushprimit_texdef.coords[1][1]=ST[2][4]-f->brushprimit_texdef.coords[1][2];
}

// compute texture coordinates for the winding points
void EmitBrushPrimitTextureCoordinates(face_t * f, Winding * w)
{
	Vector3 texX,texY;
	float x,y;
	// compute axis base
	ComputeAxisBase(f->plane.normal,texX,texY);
	// in case the texcoords matrix is empty, build a default one
	// same behaviour as if scale[0]==0 && scale[1]==0 in old code
	if (f->brushprimit_texdef.coords[0][0]==0 && f->brushprimit_texdef.coords[1][0]==0 && f->brushprimit_texdef.coords[0][1]==0 && f->brushprimit_texdef.coords[1][1]==0)
	{
		f->brushprimit_texdef.coords[0][0] = 1.0f;
		f->brushprimit_texdef.coords[1][1] = 1.0f;
		ConvertTexMatWithQTexture( &f->brushprimit_texdef, 0, &f->brushprimit_texdef, f->pShader->getTexture() );
	}
	int i;
    for (i=0 ; i<w.numpoints ; i++)
	{
		x=vector3_dot(w.point_at(i),texX);
		y=vector3_dot(w.point_at(i),texY);
#if 0
#ifdef DBG_BP
		if (g_bp_globals.bNeedConvert)
		{
			// check we compute the same ST as the traditional texture computation used before
			float S=f->brushprimit_texdef.coords[0][0]*x+f->brushprimit_texdef.coords[0][1]*y+f->brushprimit_texdef.coords[0][2];
			float T=f->brushprimit_texdef.coords[1][0]*x+f->brushprimit_texdef.coords[1][1]*y+f->brushprimit_texdef.coords[1][2];
			if ( fabs(S-w.point_at(i)[3])>1e-2 || fabs(T-w.point_at(i)[4])>1e-2 )
			{
				if ( fabs(S-w.point_at(i)[3])>1e-4 || fabs(T-w.point_at(i)[4])>1e-4 )
					globalOutputStream() << "Warning : precision loss in brush -> brush primitive texture computation\n";
				else
					globalOutputStream() << "Warning : brush -> brush primitive texture computation bug detected\n";
			}
		}
#endif
#endif
		w.point_at(i)[3]=f->brushprimit_texdef.coords[0][0]*x+f->brushprimit_texdef.coords[0][1]*y+f->brushprimit_texdef.coords[0][2];
		w.point_at(i)[4]=f->brushprimit_texdef.coords[1][0]*x+f->brushprimit_texdef.coords[1][1]*y+f->brushprimit_texdef.coords[1][2];
	}
}
#endif

typedef float texmat_t[2][3];

void TexMat_Scale(texmat_t texmat, float s, float t)
{
	texmat[0][0] *= s;
	texmat[0][1] *= s;
	texmat[0][2] *= s;
	texmat[1][0] *= t;
	texmat[1][1] *= t;
	texmat[1][2] *= t;
}

void TexMat_Assign(texmat_t texmat, const texmat_t other)
{
	texmat[0][0] = other[0][0];
	texmat[0][1] = other[0][1];
	texmat[0][2] = other[0][2];
	texmat[1][0] = other[1][0];
	texmat[1][1] = other[1][1];
	texmat[1][2] = other[1][2];
}

void ConvertTexMatWithDimensions(const texmat_t texmat1, std::size_t w1, std::size_t h1,
                                 texmat_t texmat2, std::size_t w2, std::size_t h2)
{
  TexMat_Assign(texmat2, texmat1);
  TexMat_Scale(texmat2, static_cast<float>(w1) / static_cast<float>(w2), static_cast<float>(h1) / static_cast<float>(h2));
}

#if 0
// convert a texture matrix between two qtexture_t
// if 0 for qtexture_t, basic 2x2 texture is assumed ( straight mapping between s/t coordinates and geometric coordinates )
void ConvertTexMatWithQTexture( const float texMat1[2][3], const qtexture_t *qtex1, float texMat2[2][3], const qtexture_t *qtex2 )
{
  ConvertTexMatWithDimensions(texMat1, (qtex1) ? qtex1->width : 2, (qtex1) ? qtex1->height : 2,
                              texMat2, (qtex2) ? qtex2->width : 2, (qtex2) ? qtex2->height : 2);
}

void ConvertTexMatWithQTexture( const brushprimit_texdef_t *texMat1, const qtexture_t *qtex1, brushprimit_texdef_t *texMat2, const qtexture_t *qtex2 )
{
  ConvertTexMatWithQTexture(texMat1->coords, qtex1, texMat2->coords, qtex2);
}
#endif

// compute a fake shift scale rot representation from the texture matrix
// these shift scale rot values are to be understood in the local axis base
// Note: this code looks similar to Texdef_fromTransform, but the algorithm is slightly different.

void TexMatToFakeTexCoords(const brushprimit_texdef_t& bp_texdef, texdef_t& texdef)
{
  texdef.scale[0] = static_cast<float>(1.0 / vector2_length(Vector2(bp_texdef.coords[0][0], bp_texdef.coords[1][0])));
  texdef.scale[1] = static_cast<float>(1.0 / vector2_length(Vector2(bp_texdef.coords[0][1], bp_texdef.coords[1][1])));

  texdef.rotate = -static_cast<float>(radians_to_degrees(arctangent_yx(bp_texdef.coords[1][0], bp_texdef.coords[0][0])));

  texdef.shift[0] = -bp_texdef.coords[0][2];
  texdef.shift[1] = bp_texdef.coords[1][2];

  // determine whether or not an axis is flipped using a 2d cross-product
  double cross = vector2_cross(Vector2(bp_texdef.coords[0][0], bp_texdef.coords[0][1]), Vector2(bp_texdef.coords[1][0], bp_texdef.coords[1][1]));
  if(cross < 0)
  {
    // This is a bit of a compromise when using BPs--since we don't know *which* axis was flipped,
    // we pick one (rather arbitrarily) using the following convention: If the X-axis is between
    // 0 and 180, we assume it's the Y-axis that flipped, otherwise we assume it's the X-axis and
    // subtract out 180 degrees to compensate.
    if(texdef.rotate >= 180.0f)
    {
      texdef.rotate -= 180.0f;
      texdef.scale[0] = -texdef.scale[0];
    }
    else
    {
      texdef.scale[1] = -texdef.scale[1];
    }
  }
}

// compute back the texture matrix from fake shift scale rot
void FakeTexCoordsToTexMat(const texdef_t& texdef, brushprimit_texdef_t& bp_texdef)
{
  double r = degrees_to_radians(-texdef.rotate);
  double c = cos(r);
  double s = sin(r);
  double x = 1.0f / texdef.scale[0];
  double y = 1.0f / texdef.scale[1];
  bp_texdef.coords[0][0] = static_cast<float>(x * c);
  bp_texdef.coords[1][0] = static_cast<float>(x * s);
  bp_texdef.coords[0][1] = static_cast<float>(y * -s);
  bp_texdef.coords[1][1] = static_cast<float>(y * c);
  bp_texdef.coords[0][2] = -texdef.shift[0];
  bp_texdef.coords[1][2] = texdef.shift[1];
}

#if 0 // texture locking (brush primit)
// used for texture locking
// will move the texture according to a geometric vector
void ShiftTextureGeometric_BrushPrimit(face_t *f, Vector3& delta)
{
	Vector3 texS,texT;
	float tx,ty;
	Vector3 M[3]; // columns of the matrix .. easier that way
	float det;
	Vector3 D[2];
	// compute plane axis base ( doesn't change with translation )
	ComputeAxisBase( f->plane.normal, texS, texT );
	// compute translation vector in plane axis base
	tx = vector3_dot( delta, texS );
	ty = vector3_dot( delta, texT );
	// fill the data vectors
	M[0][0]=tx; M[0][1]=1.0f+tx; M[0][2]=tx;
	M[1][0]=ty; M[1][1]=ty; M[1][2]=1.0f+ty;
	M[2][0]=1.0f; M[2][1]=1.0f; M[2][2]=1.0f;
	D[0][0]=f->brushprimit_texdef.coords[0][2];
	D[0][1]=f->brushprimit_texdef.coords[0][0]+f->brushprimit_texdef.coords[0][2];
	D[0][2]=f->brushprimit_texdef.coords[0][1]+f->brushprimit_texdef.coords[0][2];
	D[1][0]=f->brushprimit_texdef.coords[1][2];
	D[1][1]=f->brushprimit_texdef.coords[1][0]+f->brushprimit_texdef.coords[1][2];
	D[1][2]=f->brushprimit_texdef.coords[1][1]+f->brushprimit_texdef.coords[1][2];
	// solve
	det = SarrusDet( M[0], M[1], M[2] );
	f->brushprimit_texdef.coords[0][0] = SarrusDet( D[0], M[1], M[2] ) / det;
	f->brushprimit_texdef.coords[0][1] = SarrusDet( M[0], D[0], M[2] ) / det;
	f->brushprimit_texdef.coords[0][2] = SarrusDet( M[0], M[1], D[0] ) / det;
	f->brushprimit_texdef.coords[1][0] = SarrusDet( D[1], M[1], M[2] ) / det;
	f->brushprimit_texdef.coords[1][1] = SarrusDet( M[0], D[1], M[2] ) / det;
	f->brushprimit_texdef.coords[1][2] = SarrusDet( M[0], M[1], D[1] ) / det;
}

// shift a texture (texture adjustments) along it's current texture axes
// x and y are geometric values, which we must compute as ST increments
// this depends on the texture size and the pixel/texel ratio
void ShiftTextureRelative_BrushPrimit( face_t *f, float x, float y)
{
  float s,t;
  // as a ratio against texture size
  // the scale of the texture is not relevant here (we work directly on a transformation from the base vectors)
  s = (x * 2.0) / (float)f->pShader->getTexture().width;
  t = (y * 2.0) / (float)f->pShader->getTexture().height;
  f->brushprimit_texdef.coords[0][2] -= s;
  f->brushprimit_texdef.coords[1][2] -= t;
}
#endif

// TTimo: FIXME: I don't like that, it feels broken
//   (and it's likely that it's not used anymore)
// best fitted 2D vector is x.X+y.Y
void ComputeBest2DVector( Vector3& v, Vector3& X, Vector3& Y, int &x, int &y )
{
	double sx,sy;
	sx = vector3_dot( v, X );
	sy = vector3_dot( v, Y );
	if ( fabs(sy) > fabs(sx) )
  {
		x = 0;
		if ( sy > 0.0 )
			y =  1;
		else
			y = -1;
	}
	else
	{
		y = 0;
		if ( sx > 0.0 )
			x =  1;
		else
			x = -1;
	}
}


#if 0 // texdef conversion
void BrushPrimitFaceToFace(face_t *face)
{
  // we have parsed brush primitives and need conversion back to standard format
  // NOTE: converting back is a quick hack, there's some information lost and we can't do anything about it
  // FIXME: if we normalize the texture matrix to a standard 2x2 size, we end up with wrong scaling
  // I tried various tweaks, no luck .. seems shifting is lost
  brushprimit_texdef_t aux;
  ConvertTexMatWithQTexture( &face->brushprimit_texdef, face->pShader->getTexture(), &aux, 0 );
  TexMatToFakeTexCoords( aux.coords, face->texdef.shift, &face->texdef.rotate, face->texdef.scale );
  face->texdef.scale[0]/=2.0;
  face->texdef.scale[1]/=2.0;
}
#endif


#if 0 // texture locking (brush primit)
// TEXTURE LOCKING -----------------------------------------------------------------------------------------------------
// (Relevant to the editor only?)

// internally used for texture locking on rotation and flipping
// the general algorithm is the same for both lockings, it's only the geometric transformation part that changes
// so I wanted to keep it in a single function
// if there are more linear transformations that need the locking, going to a C++ or code pointer solution would be best
// (but right now I want to keep brush_primit.cpp striclty C)

bool txlock_bRotation;

// rotation locking params
int txl_nAxis;
float txl_fDeg;
Vector3 txl_vOrigin;

// flip locking params
Vector3 txl_matrix[3];
Vector3 txl_origin;

void TextureLockTransformation_BrushPrimit(face_t *f)
{
  Vector3 Orig,texS,texT;        // axis base of initial plane
  // used by transformation algo
  Vector3 temp; int j;
	Vector3 vRotate;				        // rotation vector

  Vector3 rOrig,rvecS,rvecT;     // geometric transformation of (0,0) (1,0) (0,1) { initial plane axis base }
  Vector3 rNormal,rtexS,rtexT;   // axis base for the transformed plane
	Vector3 lOrig,lvecS,lvecT;	// [2] are not used ( but usefull for debugging )
	Vector3 M[3];
	float det;
	Vector3 D[2];

	// compute plane axis base
	ComputeAxisBase( f->plane.normal, texS, texT );
  VectorSet(Orig, 0.0f, 0.0f, 0.0f);

	// compute coordinates of (0,0) (1,0) (0,1) ( expressed in initial plane axis base ) after transformation
	// (0,0) (1,0) (0,1) ( expressed in initial plane axis base ) <-> (0,0,0) texS texT ( expressed world axis base )
  // input: Orig, texS, texT (and the global locking params)
  // ouput: rOrig, rvecS, rvecT, rNormal
  if (txlock_bRotation) {
    // rotation vector
  	VectorSet( vRotate, 0.0f, 0.0f, 0.0f );
  	vRotate[txl_nAxis]=txl_fDeg;
  	VectorRotateOrigin ( Orig, vRotate, txl_vOrigin, rOrig );
  	VectorRotateOrigin ( texS, vRotate, txl_vOrigin, rvecS );
  	VectorRotateOrigin ( texT, vRotate, txl_vOrigin, rvecT );
  	// compute normal of plane after rotation
  	VectorRotate ( f->plane.normal, vRotate, rNormal );
  }
  else
  {
    for (j=0 ; j<3 ; j++)
      rOrig[j] = vector3_dot(vector3_subtracted(Orig, txl_origin), txl_matrix[j]) + txl_origin[j];
    for (j=0 ; j<3 ; j++)
      rvecS[j] = vector3_dot(vector3_subtracted(texS, txl_origin), txl_matrix[j]) + txl_origin[j];
    for (j=0 ; j<3 ; j++)
      rvecT[j] = vector3_dot(vector3_subtracted(texT, txl_origin), txl_matrix[j]) + txl_origin[j];
    // we also need the axis base of the target plane, apply the transformation matrix to the normal too..
    for (j=0 ; j<3 ; j++)
      rNormal[j] = vector3_dot(f->plane.normal, txl_matrix[j]);
  }

	// compute rotated plane axis base
	ComputeAxisBase( rNormal, rtexS, rtexT );
	// compute S/T coordinates of the three points in rotated axis base ( in M matrix )
	lOrig[0] = vector3_dot( rOrig, rtexS );
	lOrig[1] = vector3_dot( rOrig, rtexT );
	lvecS[0] = vector3_dot( rvecS, rtexS );
	lvecS[1] = vector3_dot( rvecS, rtexT );
	lvecT[0] = vector3_dot( rvecT, rtexS );
	lvecT[1] = vector3_dot( rvecT, rtexT );
	M[0][0] = lOrig[0]; M[1][0] = lOrig[1]; M[2][0] = 1.0f;
	M[0][1] = lvecS[0]; M[1][1] = lvecS[1]; M[2][1] = 1.0f;
	M[0][2] = lvecT[0]; M[1][2] = lvecT[1]; M[2][2] = 1.0f;
	// fill data vector
	D[0][0]=f->brushprimit_texdef.coords[0][2];
	D[0][1]=f->brushprimit_texdef.coords[0][0]+f->brushprimit_texdef.coords[0][2];
	D[0][2]=f->brushprimit_texdef.coords[0][1]+f->brushprimit_texdef.coords[0][2];
	D[1][0]=f->brushprimit_texdef.coords[1][2];
	D[1][1]=f->brushprimit_texdef.coords[1][0]+f->brushprimit_texdef.coords[1][2];
	D[1][2]=f->brushprimit_texdef.coords[1][1]+f->brushprimit_texdef.coords[1][2];
	// solve
	det = SarrusDet( M[0], M[1], M[2] );
	f->brushprimit_texdef.coords[0][0] = SarrusDet( D[0], M[1], M[2] ) / det;
	f->brushprimit_texdef.coords[0][1] = SarrusDet( M[0], D[0], M[2] ) / det;
	f->brushprimit_texdef.coords[0][2] = SarrusDet( M[0], M[1], D[0] ) / det;
	f->brushprimit_texdef.coords[1][0] = SarrusDet( D[1], M[1], M[2] ) / det;
	f->brushprimit_texdef.coords[1][1] = SarrusDet( M[0], D[1], M[2] ) / det;
	f->brushprimit_texdef.coords[1][2] = SarrusDet( M[0], M[1], D[1] ) / det;
}

// texture locking
// called before the points on the face are actually rotated
void RotateFaceTexture_BrushPrimit(face_t *f, int nAxis, float fDeg, Vector3& vOrigin )
{
  // this is a placeholder to call the general texture locking algorithm
  txlock_bRotation = true;
  txl_nAxis = nAxis;
  txl_fDeg = fDeg;
  VectorCopy(vOrigin, txl_vOrigin);
  TextureLockTransformation_BrushPrimit(f);
}

// compute the new brush primit texture matrix for a transformation matrix and a flip order flag (change plane orientation)
// this matches the select_matrix algo used in select.cpp
// this needs to be called on the face BEFORE any geometric transformation
// it will compute the texture matrix that will represent the same texture on the face after the geometric transformation is done
void ApplyMatrix_BrushPrimit(face_t *f, Vector3 matrix[3], Vector3& origin)
{
  // this is a placeholder to call the general texture locking algorithm
  txlock_bRotation = false;
  VectorCopy(matrix[0], txl_matrix[0]);
  VectorCopy(matrix[1], txl_matrix[1]);
  VectorCopy(matrix[2], txl_matrix[2]);
  VectorCopy(origin, txl_origin);
  TextureLockTransformation_BrushPrimit(f);
}
#endif

// don't do C==A!
void BPMatMul(float A[2][3], float B[2][3], float C[2][3])
{
  C[0][0] = A[0][0]*B[0][0]+A[0][1]*B[1][0];
  C[1][0] = A[1][0]*B[0][0]+A[1][1]*B[1][0];
  C[0][1] = A[0][0]*B[0][1]+A[0][1]*B[1][1];
  C[1][1] = A[1][0]*B[0][1]+A[1][1]*B[1][1];
  C[0][2] = A[0][0]*B[0][2]+A[0][1]*B[1][2]+A[0][2];
  C[1][2] = A[1][0]*B[0][2]+A[1][1]*B[1][2]+A[1][2];
}

void BPMatDump(float A[2][3])
{
  globalOutputStream() << "" << A[0][0]
    << " " << A[0][1]
    << " " << A[0][2]
    << "\n" << A[1][0]
    << " " << A[1][2]
    << " " << A[1][2]
    << "\n0 0 1\n";
}

void BPMatRotate(float A[2][3], float theta)
{
  float m[2][3];
  float aux[2][3];
  memset(&m, 0, sizeof(float)*6);
  m[0][0] = static_cast<float>(cos(degrees_to_radians(theta)));
  m[0][1] = static_cast<float>(-sin(degrees_to_radians(theta)));
  m[1][0] = -m[0][1];
  m[1][1] = m[0][0];
  BPMatMul(A, m, aux);
  BPMatCopy(aux,A);
}

#if 0 // camera-relative texture shift
// get the relative axes of the current texturing
void BrushPrimit_GetRelativeAxes(face_t *f, Vector3& vecS, Vector3& vecT)
{
  float vS[2],vT[2];
  // first we compute them as expressed in plane axis base
  // BP matrix has coordinates of plane axis base expressed in geometric axis base
  // so we use the line vectors
  vS[0] = f->brushprimit_texdef.coords[0][0];
  vS[1] = f->brushprimit_texdef.coords[0][1];
  vT[0] = f->brushprimit_texdef.coords[1][0];
  vT[1] = f->brushprimit_texdef.coords[1][1];
  // now compute those vectors in geometric space
  Vector3 texS, texT; // axis base of the plane (geometric)
  ComputeAxisBase(f->plane.normal, texS, texT);
  // vecS[] = vS[0].texS[] + vS[1].texT[]
  // vecT[] = vT[0].texS[] + vT[1].texT[]
  vecS[0] = vS[0]*texS[0] + vS[1]*texT[0];
  vecS[1] = vS[0]*texS[1] + vS[1]*texT[1];
  vecS[2] = vS[0]*texS[2] + vS[1]*texT[2];
  vecT[0] = vT[0]*texS[0] + vT[1]*texT[0];
  vecT[1] = vT[0]*texS[1] + vT[1]*texT[1];
  vecT[2] = vT[0]*texS[2] + vT[1]*texT[2];
}

// brush primitive texture adjustments, use the camera view to map adjustments
// ShiftTextureRelative_BrushPrimit ( s , t ) will shift relative to the texture
void ShiftTextureRelative_Camera(face_t *f, int x, int y)
{
  Vector3 vecS, vecT;
  float XY[2]; // the values we are going to send for translation
  float sgn[2]; // +1 or -1
  int axis[2];
  CamWnd* pCam;

  // get the two relative texture axes for the current texturing
  BrushPrimit_GetRelativeAxes(f, vecS, vecT);

  // center point of the face, project it on the camera space
  Vector3 C;
  VectorClear(C);
  int i;
  for (i=0; i<f->face_winding->numpoints; i++)
  {
    VectorAdd(C,f->face_winding->point_at(i),C);
  }
  VectorScale(C,1.0/f->face_winding->numpoints,C);

  pCam = g_pParentWnd->GetCamWnd();
  pCam->MatchViewAxes(C, vecS, axis[0], sgn[0]);
  pCam->MatchViewAxes(C, vecT, axis[1], sgn[1]);
  
  // this happens when the two directions can't be mapped on two different directions on the screen
  // then the move will occur against a single axis
  // (i.e. the user is not positioned well enough to send understandable shift commands)
  // NOTE: in most cases this warning is not very relevant because the user would use one of the two axes
  // for which the solution is easy (the other one being unknown)
  // so this warning could be removed
  if (axis[0] == axis[1])
    globalOutputStream() << "Warning: degenerate in ShiftTextureRelative_Camera\n";

  // compute the X Y geometric increments
  // those geometric increments will be applied along the texture axes (the ones we computed above)
  XY[0] = 0;
  XY[1] = 0;
  if (x!=0)
  {
    // moving right/left
    XY[axis[0]] += sgn[0]*x;
  }
  if (y!=0)
  {
    XY[axis[1]] += sgn[1]*y;
  }
  // we worked out a move along vecS vecT, and we now it's geometric amplitude
  // apply it
  ShiftTextureRelative_BrushPrimit(f, XY[0], XY[1]);
}
#endif


void BPTexdef_Assign(brushprimit_texdef_t& bp_td, const brushprimit_texdef_t& bp_other)
{
 	bp_td = bp_other;
}

void BPTexdef_Shift(brushprimit_texdef_t& bp_td, float s, float t)
{
  // shift a texture (texture adjustments) along it's current texture axes
  // x and y are geometric values, which we must compute as ST increments
  // this depends on the texture size and the pixel/texel ratio
  // as a ratio against texture size
  // the scale of the texture is not relevant here (we work directly on a transformation from the base vectors)
  bp_td.coords[0][2] -= s;
  bp_td.coords[1][2] += t;
}

void BPTexdef_Scale(brushprimit_texdef_t& bp_td, float s, float t)
{
	// apply same scale as the spinner button of the surface inspector
	texdef_t texdef;
	// compute fake shift scale rot
	TexMatToFakeTexCoords( bp_td, texdef );
	// update
	texdef.scale[0] += s;
	texdef.scale[1] += t;
	// compute new normalized texture matrix
	FakeTexCoordsToTexMat( texdef, bp_td );
}

void BPTexdef_Rotate(brushprimit_texdef_t& bp_td, float angle)
{
	// apply same scale as the spinner button of the surface inspector
	texdef_t texdef;
	// compute fake shift scale rot
	TexMatToFakeTexCoords( bp_td, texdef );
	// update
	texdef.rotate += angle;
	// compute new normalized texture matrix
	FakeTexCoordsToTexMat( texdef, bp_td );
}

void BPTexdef_Construct(brushprimit_texdef_t& bp_td, std::size_t width, std::size_t height)
{
	bp_td.coords[0][0] = 1.0f;
	bp_td.coords[1][1] = 1.0f;
	ConvertTexMatWithDimensions(bp_td.coords, 2, 2, bp_td.coords, width, height);
}

void Texdef_Assign(TextureProjection& projection, const TextureProjection& other)
{
  if (g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
  {
    BPTexdef_Assign(projection.m_brushprimit_texdef, other.m_brushprimit_texdef);
  }
  else
  {
    Texdef_Assign(projection.m_texdef, other.m_texdef);
    if(g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_HALFLIFE)
    {
      projection.m_basis_s = other.m_basis_s;
      projection.m_basis_t = other.m_basis_t;
    }
  }
}

void Texdef_Shift(TextureProjection& projection, float s, float t)
{
  if (g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
  {
    BPTexdef_Shift(projection.m_brushprimit_texdef, s, t);
  }
  else
  {
		Texdef_Shift(projection.m_texdef, s, t);
  }
}

void Texdef_Scale(TextureProjection& projection, float s, float t)
{
	if (g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
	{
    BPTexdef_Scale(projection.m_brushprimit_texdef, s, t);
	}
	else
	{
		Texdef_Scale(projection.m_texdef, s, t);
	}
}

void Texdef_Rotate(TextureProjection& projection, float angle)
{
	if (g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
	{
    BPTexdef_Rotate(projection.m_brushprimit_texdef, angle);
	}
	else
	{
		Texdef_Rotate(projection.m_texdef, angle);
	}
}

void Texdef_FitTexture(TextureProjection& projection, std::size_t width, std::size_t height, const Vector3& normal, const Winding& w, float s_repeat, float t_repeat)
{
  if(w.numpoints < 3)
  {
    return;
  }

  Matrix4 st2tex;
  Texdef_toTransform(projection, (float)width, (float)height, st2tex);

  // the current texture transform
  Matrix4 local2tex = st2tex;
  {
    Matrix4 xyz2st; 
    Texdef_basisForNormal(projection, normal, xyz2st);
    matrix4_multiply_by_matrix4(local2tex, xyz2st);
  }

  // the bounds of the current texture transform
  AABB bounds;
  for(Winding::const_iterator i = w.begin(); i != w.end(); ++i)
  {
    Vector3 texcoord = matrix4_transformed_point(local2tex, (*i).vertex);
    aabb_extend_by_point_safe(bounds, texcoord);
  }
  bounds.origin.z() = 0;
  bounds.extents.z() = 1;

  // the bounds of a perfectly fitted texture transform
  AABB perfect(Vector3(s_repeat * 0.5, t_repeat * 0.5, 0), Vector3(s_repeat * 0.5, t_repeat * 0.5, 1));

  // the difference between the current texture transform and the perfectly fitted transform
  Matrix4 matrix(matrix4_translation_for_vec3(bounds.origin - perfect.origin));
  matrix4_pivoted_scale_by_vec3(matrix, bounds.extents / perfect.extents, perfect.origin);
  matrix4_affine_invert(matrix);

  // apply the difference to the current texture transform
  matrix4_premultiply_by_matrix4(st2tex, matrix);

  Texdef_fromTransform(projection, (float)width, (float)height, st2tex);
  Texdef_normalise(projection, (float)width, (float)height);
}

float Texdef_getDefaultTextureScale()
{
  return g_texdef_default_scale;
}

void TexDef_Construct_Default(TextureProjection& projection)
{
  projection.m_texdef.scale[0] = Texdef_getDefaultTextureScale();
  projection.m_texdef.scale[1] = Texdef_getDefaultTextureScale();

  if(g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
  {
    FakeTexCoordsToTexMat(projection.m_texdef, projection.m_brushprimit_texdef);
  }
}



void ShiftScaleRotate_fromFace(texdef_t& shiftScaleRotate, const TextureProjection& projection)
{
  if(g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
  {
    TexMatToFakeTexCoords(projection.m_brushprimit_texdef, shiftScaleRotate);
  }
  else
  {
    shiftScaleRotate = projection.m_texdef;
  }
}

void ShiftScaleRotate_toFace(const texdef_t& shiftScaleRotate, TextureProjection& projection)
{
  if (g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_BRUSHPRIMITIVES)
  {
    // compute texture matrix
    // the matrix returned must be understood as a qtexture_t with width=2 height=2
    FakeTexCoordsToTexMat( shiftScaleRotate, projection.m_brushprimit_texdef );
  }
  else
  {
    projection.m_texdef = shiftScaleRotate;
  }
}


inline void print_vector3(const Vector3& v)
{
  globalOutputStream() << "( " << v.x() << " " << v.y() << " " << v.z() << " )\n";
}

inline void print_3x3(const Matrix4& m)
{
  globalOutputStream() << "( " << m.xx() << " " << m.xy() << " " << m.xz() << " ) "
    << "( " << m.yx() << " " << m.yy() << " " << m.yz() << " ) "
    << "( " << m.zx() << " " << m.zy() << " " << m.zz() << " )\n";
}


inline Matrix4 matrix4_rotation_for_vector3(const Vector3& x, const Vector3& y, const Vector3& z)
{
  return Matrix4(
    x.x(), x.y(), x.z(), 0,
    y.x(), y.y(), y.z(), 0,
    z.x(), z.y(), z.z(), 0,
    0, 0, 0, 1
  );
}

inline Matrix4 matrix4_swap_axes(const Vector3& from, const Vector3& to)
{
  if(from.x() != 0 && to.y() != 0)
  {
    return matrix4_rotation_for_vector3(to, from, g_vector3_axis_z);
  }

  if(from.x() != 0 && to.z() != 0)
  {
    return matrix4_rotation_for_vector3(to, g_vector3_axis_y, from);
  }

  if(from.y() != 0 && to.z() != 0)
  {
    return matrix4_rotation_for_vector3(g_vector3_axis_x, to, from);
  }

  if(from.y() != 0 && to.x() != 0)
  {
    return matrix4_rotation_for_vector3(from, to, g_vector3_axis_z);
  }

  if(from.z() != 0 && to.x() != 0)
  {
    return matrix4_rotation_for_vector3(from, g_vector3_axis_y, to);
  }

  if(from.z() != 0 && to.y() != 0)
  {
    return matrix4_rotation_for_vector3(g_vector3_axis_x, from, to);
  }

  ERROR_MESSAGE("unhandled axis swap case");

  return g_matrix4_identity;
}

inline Matrix4 matrix4_reflection_for_plane(const Plane3& plane)
{
  return Matrix4(
    static_cast<float>(1 - (2 * plane.a * plane.a)),
    static_cast<float>(-2 * plane.a * plane.b),
    static_cast<float>(-2 * plane.a * plane.c),
    0,
    static_cast<float>(-2 * plane.b * plane.a),
    static_cast<float>(1 - (2 * plane.b * plane.b)),
    static_cast<float>(-2 * plane.b * plane.c),
    0,
    static_cast<float>(-2 * plane.c * plane.a),
    static_cast<float>(-2 * plane.c * plane.b),
    static_cast<float>(1 - (2 * plane.c * plane.c)),
    0,
    static_cast<float>(-2 * plane.d * plane.a),
    static_cast<float>(-2 * plane.d * plane.b),
    static_cast<float>(-2 * plane.d * plane.c),
    1
  );
}

inline Matrix4 matrix4_reflection_for_plane45(const Plane3& plane, const Vector3& from, const Vector3& to)
{
  Vector3 first = from;
  Vector3 second = to;

  if(vector3_dot(from, plane.normal()) > 0 == vector3_dot(to, plane.normal()) > 0)
  {
    first = vector3_negated(first);
    second = vector3_negated(second);
  }

#if 0
  globalOutputStream() << "normal: ";
  print_vector3(plane.normal());

  globalOutputStream() << "from: ";
  print_vector3(first);

  globalOutputStream() << "to: ";
  print_vector3(second);
#endif

  Matrix4 swap = matrix4_swap_axes(first, second);

  Matrix4 tmp = matrix4_reflection_for_plane(plane);

  swap.tx() = -static_cast<float>(-2 * plane.a * plane.d);
  swap.ty() = -static_cast<float>(-2 * plane.b * plane.d);
  swap.tz() = -static_cast<float>(-2 * plane.c * plane.d);

  return swap;
}

void Texdef_transformLocked(TextureProjection& projection, std::size_t width, std::size_t height, const Plane3& plane, const Matrix4& identity2transformed)
{
  //globalOutputStream() << "identity2transformed: " << identity2transformed << "\n";

  //globalOutputStream() << "plane.normal(): " << plane.normal() << "\n";

  Vector3 normalTransformed(matrix4_transformed_direction(identity2transformed, plane.normal()));

  //globalOutputStream() << "normalTransformed: " << normalTransformed << "\n";

  // identity: identity space
  // transformed: transformation
  // stIdentity: base st projection space before transformation
  // stTransformed: base st projection space after transformation
  // stOriginal: original texdef space

  // stTransformed2stOriginal = stTransformed -> transformed -> identity -> stIdentity -> stOriginal

  Matrix4 identity2stIdentity;
  Texdef_basisForNormal(projection, plane.normal(), identity2stIdentity);
  //globalOutputStream() << "identity2stIdentity: " << identity2stIdentity << "\n";

  if(g_bp_globals.m_texdefTypeId == TEXDEFTYPEID_HALFLIFE)
  {
    matrix4_transform_direction(identity2transformed, projection.m_basis_s);
    matrix4_transform_direction(identity2transformed, projection.m_basis_t);
  }

  Matrix4 transformed2stTransformed;
  Texdef_basisForNormal(projection, normalTransformed, transformed2stTransformed);

  Matrix4 stTransformed2identity(matrix4_affine_inverse(matrix4_multiplied_by_matrix4(transformed2stTransformed, identity2transformed)));

  Vector3 originalProjectionAxis(vector4_to_vector3(matrix4_affine_inverse(identity2stIdentity).z()));

  Vector3 transformedProjectionAxis(vector4_to_vector3(stTransformed2identity.z()));

  Matrix4 stIdentity2stOriginal;
  Texdef_toTransform(projection, (float)width, (float)height, stIdentity2stOriginal);
  Matrix4 identity2stOriginal(matrix4_multiplied_by_matrix4(stIdentity2stOriginal, identity2stIdentity));

  //globalOutputStream() << "originalProj: " << originalProjectionAxis << "\n";
  //globalOutputStream() << "transformedProj: " << transformedProjectionAxis << "\n";
  double dot = vector3_dot(originalProjectionAxis, transformedProjectionAxis);
  //globalOutputStream() << "dot: " << dot << "\n";
  if(dot == 0)
  {
    // The projection axis chosen for the transformed normal is at 90 degrees
    // to the transformed projection axis chosen for the original normal.
    // This happens when the projection axis is ambiguous - e.g. for the plane
    // 'X == Y' the projection axis could be either X or Y.
    //globalOutputStream() << "flipped\n";
#if 0
    globalOutputStream() << "projection off by 90\n";
    globalOutputStream() << "normal: ";
    print_vector3(plane.normal());
    globalOutputStream() << "original projection: ";
    print_vector3(originalProjectionAxis);
    globalOutputStream() << "transformed projection: ";
    print_vector3(transformedProjectionAxis);
#endif

    Matrix4 identityCorrected = matrix4_reflection_for_plane45(plane, originalProjectionAxis, transformedProjectionAxis);

    identity2stOriginal = matrix4_multiplied_by_matrix4(identity2stOriginal, identityCorrected);
  }

  Matrix4 stTransformed2stOriginal = matrix4_multiplied_by_matrix4(identity2stOriginal, stTransformed2identity);

  Texdef_fromTransform(projection, (float)width, (float)height, stTransformed2stOriginal);
  Texdef_normalise(projection, (float)width, (float)height);
}

#if 1
void Q3_to_matrix(const texdef_t& texdef, float width, float height, const Vector3& normal, Matrix4& matrix)
{
  Normal_GetTransform(normal, matrix);

  Matrix4 transform;
  
  Texdef_toTransform(texdef, width, height, transform);

  matrix4_multiply_by_matrix4(matrix, transform);
}

void BP_from_matrix(brushprimit_texdef_t& bp_texdef, const Vector3& normal, const Matrix4& transform)
{
  Matrix4 basis;
  basis = g_matrix4_identity;
  ComputeAxisBase(normal, vector4_to_vector3(basis.x()), vector4_to_vector3(basis.y()));
  vector4_to_vector3(basis.z()) = normal;
  matrix4_transpose(basis);
  matrix4_affine_invert(basis);

  Matrix4 basis2texture = matrix4_multiplied_by_matrix4(basis, transform);

  BPTexdef_fromTransform(bp_texdef, basis2texture);
}

void Q3_to_BP(const texdef_t& texdef, float width, float height, const Vector3& normal, brushprimit_texdef_t& bp_texdef)
{
  Matrix4 matrix;
  Q3_to_matrix(texdef, width, height, normal, matrix);
  BP_from_matrix(bp_texdef, normal, matrix);
}
#endif