/*
** texture.cpp
** The base texture class
**
**---------------------------------------------------------------------------
** Copyright 2004-2007 Randy Heit
** Copyright 2006-2018 Christoph Oelckers
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** 1. Redistributions of source code must retain the above copyright
**    notice, this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright
**    notice, this list of conditions and the following disclaimer in the
**    documentation and/or other materials provided with the distribution.
** 3. The name of the author may not be used to endorse or promote products
**    derived from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**---------------------------------------------------------------------------
**
**
*/

#include "doomtype.h"
#include "files.h"
#include "w_wad.h"
#include "templates.h"
#include "i_system.h"
#include "r_data/r_translate.h"
#include "bitmap.h"
#include "colormatcher.h"
#include "c_dispatch.h"
#include "v_video.h"
#include "m_fixed.h"
#include "hwrenderer/textures/hw_material.h"
#include "hwrenderer/textures/hw_ihwtexture.h"
#include "swrenderer/textures/r_swtexture.h"
#include "imagehelpers.h"
#include "image.h"
#include "formats/multipatchtexture.h"
#include "g_levellocals.h"

FTexture *CreateBrightmapTexture(FImageSource*);

// Make sprite offset adjustment user-configurable per renderer.
int r_spriteadjustSW, r_spriteadjustHW;
CUSTOM_CVAR(Int, r_spriteadjust, 2, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
{
	r_spriteadjustHW = !!(self & 2);
	r_spriteadjustSW = !!(self & 1);
	TexMan.SpriteAdjustChanged();
}

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

uint8_t ImageHelpers::GrayMap[256];

void FTexture::InitGrayMap()
{
	for (int i = 0; i < 256; ++i)
	{
		ImageHelpers::GrayMap[i] = ColorMatcher.Pick(i, i, i);
	}
}


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


// Examines the lump contents to decide what type of texture to create,
// and creates the texture.
FTexture * FTexture::CreateTexture(const char *name, int lumpnum, ETextureType usetype)
{
	if (lumpnum == -1) return nullptr;

	auto image = FImageSource::GetImage(lumpnum, usetype);
	if (image != nullptr)
	{
		FTexture *tex = new FImageTexture(image);
		if (tex != nullptr) 
		{
			tex->UseType = usetype;
			if (usetype == ETextureType::Flat) 
			{
				int w = tex->GetWidth();
				int h = tex->GetHeight();

				// Auto-scale flats with dimensions 128x128 and 256x256.
				// In hindsight, a bad idea, but RandomLag made it sound better than it really is.
				// Now we're stuck with this stupid behaviour.
				if (w==128 && h==128) 
				{
					tex->Scale.X = tex->Scale.Y = 2;
					tex->bWorldPanning = true;
				}
				else if (w==256 && h==256) 
				{
					tex->Scale.X = tex->Scale.Y = 4;
					tex->bWorldPanning = true;
				}
			}
			tex->Name = name;
			tex->Name.ToUpper();
			return tex;
		}
	}
	return nullptr;
}

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

FTexture::FTexture (const char *name, int lumpnum)
	: 
  Scale(1,1), SourceLump(lumpnum),
  UseType(ETextureType::Any), bNoDecals(false), bNoRemap0(false), bWorldPanning(false),
  bMasked(true), bAlphaTexture(false), bHasCanvas(false), bWarped(0), bComplex(false), bMultiPatch(false), bKeepAround(false), bFullNameTexture(false),
	Rotations(0xFFFF), SkyOffset(0), Width(0), Height(0)
{
	bBrightmapChecked = false;
	bGlowing = false;
	bAutoGlowing = false;
	bFullbright = false;
	bDisableFullbright = false;
	bSkybox = false;
	bNoCompress = false;
	bNoExpand = false;
	bTranslucent = -1;


	_LeftOffset[0] = _LeftOffset[1] = _TopOffset[0] = _TopOffset[1] = 0;
	id.SetInvalid();
	if (name != NULL)
	{
		Name = name;
		Name.ToUpper();
	}
	else if (lumpnum < 0)
	{
		Name = FString();
	}
	else
	{
		Wads.GetLumpName (Name, lumpnum);
	}
}

FTexture::~FTexture ()
{
	FTexture *link = Wads.GetLinkedTexture(SourceLump);
	if (link == this) Wads.SetLinkedTexture(SourceLump, nullptr);
	if (areas != nullptr) delete[] areas;
	areas = nullptr;

	for (int i = 0; i < 2; i++)
	{
		if (Material[i] != nullptr) delete Material[i];
		Material[i] = nullptr;
	}
	if (SoftwareTexture != nullptr)
	{
		delete SoftwareTexture;
		SoftwareTexture = nullptr;
	}
}

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

void FTexture::SetFrontSkyLayer ()
{
	bNoRemap0 = true;
}

//===========================================================================
//
// FTexture::GetBgraBitmap
//
// Default returns just an empty bitmap. This needs to be overridden by
// any subclass that actually does return a software pixel buffer.
//
//===========================================================================

FBitmap FTexture::GetBgraBitmap(PalEntry *remap, int *ptrans)
{
	FBitmap bmp;
	bmp.Create(Width, Height);
	return bmp;
}

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

FTexture *FTexture::GetRawTexture()
{
	if (OffsetLess) return OffsetLess;
	// Reject anything that cannot have been a single-patch multipatch texture in vanilla.
	auto image = static_cast<FMultiPatchTexture *>(GetImage());
	if (bMultiPatch != 1 || UseType != ETextureType::Wall || Scale.X != 1 || Scale.Y != 1 || bWorldPanning || image == nullptr || image->NumParts != 1)
	{
		OffsetLess = this;
		return this;
	}
	// Set up a new texture that directly references the underlying patch.
	// From here we cannot retrieve the original texture made for it, so just create a new one.
	FImageSource *source = image->Parts[0].Image;
	OffsetLess = new FImageTexture(source, "");
	TexMan.AddTexture(OffsetLess);
	return OffsetLess;
}

void FTexture::SetScaledSize(int fitwidth, int fitheight)
{
	Scale.X = double(Width) / fitwidth;
	Scale.Y =double(Height) / fitheight;
	// compensate for roundoff errors
	if (int(Scale.X * fitwidth) != Width) Scale.X += (1 / 65536.);
	if (int(Scale.Y * fitheight) != Height) Scale.Y += (1 / 65536.);
}

//===========================================================================
// 
//	Gets the average color of a texture for use as a sky cap color
//
//===========================================================================

PalEntry FTexture::averageColor(const uint32_t *data, int size, int maxout)
{
	int				i;
	unsigned int	r, g, b;

	// First clear them.
	r = g = b = 0;
	if (size == 0)
	{
		return PalEntry(255, 255, 255);
	}
	for (i = 0; i < size; i++)
	{
		b += BPART(data[i]);
		g += GPART(data[i]);
		r += RPART(data[i]);
	}

	r = r / size;
	g = g / size;
	b = b / size;

	int maxv = MAX(MAX(r, g), b);

	if (maxv && maxout)
	{
		r = ::Scale(r, maxout, maxv);
		g = ::Scale(g, maxout, maxv);
		b = ::Scale(b, maxout, maxv);
	}
	return PalEntry(255, r, g, b);
}

PalEntry FTexture::GetSkyCapColor(bool bottom)
{
	if (!bSWSkyColorDone)
	{
		bSWSkyColorDone = true;

		FBitmap bitmap = GetBgraBitmap(nullptr);
		int w = bitmap.GetWidth();
		int h = bitmap.GetHeight();

		const uint32_t *buffer = (const uint32_t *)bitmap.GetPixels();
		if (buffer)
		{
			CeilingSkyColor = averageColor((uint32_t *)buffer, w * MIN(30, h), 0);
			if (h>30)
			{
				FloorSkyColor = averageColor(((uint32_t *)buffer) + (h - 30)*w, w * 30, 0);
			}
			else FloorSkyColor = CeilingSkyColor;
		}
	}
	return bottom ? FloorSkyColor : CeilingSkyColor;
}

//====================================================================
//
// CheckRealHeight
//
// Checks the posts in a texture and returns the lowest row (plus one)
// of the texture that is actually used.
//
//====================================================================

int FTexture::CheckRealHeight()
{
	auto pixels = Get8BitPixels(false);
	
	for(int h = GetHeight()-1; h>= 0; h--)
	{
		for(int w = 0; w < GetWidth(); w++)
		{
			if (pixels[h + w * GetHeight()] != 0)
			{
				// Scale maxy before returning it
				h = int((h * 2) / Scale.Y);
				h = (h >> 1) + (h & 1);
				return h;
			}
		}
	}
	return 0;
}

//==========================================================================
//
// Search auto paths for extra material textures
//
//==========================================================================

void FTexture::AddAutoMaterials()
{
	struct AutoTextureSearchPath
	{
		const char *path;
		FTexture *FTexture::*pointer;
	};

	static AutoTextureSearchPath autosearchpaths[] =
	{
		{ "brightmaps/", &FTexture::Brightmap }, // For backwards compatibility, only for short names
	{ "materials/brightmaps/", &FTexture::Brightmap },
	{ "materials/normalmaps/", &FTexture::Normal },
	{ "materials/specular/", &FTexture::Specular },
	{ "materials/metallic/", &FTexture::Metallic },
	{ "materials/roughness/", &FTexture::Roughness },
	{ "materials/ao/", &FTexture::AmbientOcclusion }
	};


	int startindex = bFullNameTexture ? 1 : 0;
	FString searchname = Name;

	if (bFullNameTexture)
	{
		auto dot = searchname.LastIndexOf('.');
		auto slash = searchname.LastIndexOf('/');
		if (dot > slash) searchname.Truncate(dot);
	}

	for (size_t i = 0; i < countof(autosearchpaths); i++)
	{
		auto &layer = autosearchpaths[i];
		if (this->*(layer.pointer) == nullptr)	// only if no explicit assignment had been done.
		{
			FStringf lookup("%s%s%s", layer.path, bFullNameTexture ? "" : "auto/", searchname.GetChars());
			auto lump = Wads.CheckNumForFullName(lookup, false, ns_global, true);
			if (lump != -1)
			{
				auto bmtex = TexMan.FindTexture(Wads.GetLumpFullName(lump), ETextureType::Any, FTextureManager::TEXMAN_TryAny);
				if (bmtex != nullptr)
				{
					bmtex->bMasked = false;
					this->*(layer.pointer) = bmtex;
				}
			}
		}
	}
}

//===========================================================================
// 
// Checks if the texture has a default brightmap and creates it if so
//
//===========================================================================
void FTexture::CreateDefaultBrightmap()
{
	if (!bBrightmapChecked)
	{
		// Check for brightmaps
		if (GetImage() && GetImage()->UseGamePalette() && TexMan.HasGlobalBrightmap &&
			UseType != ETextureType::Decal && UseType != ETextureType::MiscPatch && UseType != ETextureType::FontChar &&
			Brightmap == NULL && bWarped == 0)
		{
			// May have one - let's check when we use this texture
			auto texbuf = Get8BitPixels(false);
			const int white = ColorMatcher.Pick(255, 255, 255);

			int size = GetWidth() * GetHeight();
			for (int i = 0; i<size; i++)
			{
				if (TexMan.GlobalBrightmap.Remap[texbuf[i]] == white)
				{
					// Create a brightmap
					DPrintf(DMSG_NOTIFY, "brightmap created for texture '%s'\n", Name.GetChars());
					Brightmap = CreateBrightmapTexture(static_cast<FImageTexture*>(this)->GetImage());
					bBrightmapChecked = true;
					TexMan.AddTexture(Brightmap);
					return;
				}
			}
			// No bright pixels found
			DPrintf(DMSG_SPAMMY, "No bright pixels found in texture '%s'\n", Name.GetChars());
			bBrightmapChecked = 1;
		}
		else
		{
			// does not have one so set the flag to 'done'
			bBrightmapChecked = 1;
		}
	}
}


//==========================================================================
//
// Calculates glow color for a texture
//
//==========================================================================

void FTexture::GetGlowColor(float *data)
{
	if (bGlowing && GlowColor == 0)
	{
		auto buffer = GetBgraBitmap(nullptr);
		GlowColor = averageColor((uint32_t*)buffer.GetPixels(), buffer.GetWidth() * buffer.GetHeight(), 153);

		// Black glow equals nothing so switch glowing off
		if (GlowColor == 0) bGlowing = false;
	}
	data[0] = GlowColor.r / 255.0f;
	data[1] = GlowColor.g / 255.0f;
	data[2] = GlowColor.b / 255.0f;
}

//===========================================================================
// 
//	Finds gaps in the texture which can be skipped by the renderer
//  This was mainly added to speed up one area in E4M6 of 007LTSD
//
//===========================================================================

bool FTexture::FindHoles(const unsigned char * buffer, int w, int h)
{
	const unsigned char * li;
	int y, x;
	int startdraw, lendraw;
	int gaps[5][2];
	int gapc = 0;


	// already done!
	if (areacount) return false;
	if (UseType == ETextureType::Flat) return false;	// flats don't have transparent parts
	areacount = -1;	//whatever happens next, it shouldn't be done twice!

							// large textures are excluded for performance reasons
	if (h>512) return false;

	startdraw = -1;
	lendraw = 0;
	for (y = 0; y<h; y++)
	{
		li = buffer + w * y * 4 + 3;

		for (x = 0; x<w; x++, li += 4)
		{
			if (*li != 0) break;
		}

		if (x != w)
		{
			// non - transparent
			if (startdraw == -1)
			{
				startdraw = y;
				// merge transparent gaps of less than 16 pixels into the last drawing block
				if (gapc && y <= gaps[gapc - 1][0] + gaps[gapc - 1][1] + 16)
				{
					gapc--;
					startdraw = gaps[gapc][0];
					lendraw = y - startdraw;
				}
				if (gapc == 4) return false;	// too many splits - this isn't worth it
			}
			lendraw++;
		}
		else if (startdraw != -1)
		{
			if (lendraw == 1) lendraw = 2;
			gaps[gapc][0] = startdraw;
			gaps[gapc][1] = lendraw;
			gapc++;

			startdraw = -1;
			lendraw = 0;
		}
	}
	if (startdraw != -1)
	{
		gaps[gapc][0] = startdraw;
		gaps[gapc][1] = lendraw;
		gapc++;
	}
	if (startdraw == 0 && lendraw == h) return false;	// nothing saved so don't create a split list

	if (gapc > 0)
	{
		FloatRect * rcs = new FloatRect[gapc];

		for (x = 0; x < gapc; x++)
		{
			// gaps are stored as texture (u/v) coordinates
			rcs[x].width = rcs[x].left = -1.0f;
			rcs[x].top = (float)gaps[x][0] / (float)h;
			rcs[x].height = (float)gaps[x][1] / (float)h;
		}
		areas = rcs;
	}
	else areas = nullptr;
	areacount = gapc;

	return true;
}

//----------------------------------------------------------------------------
//
//
//
//----------------------------------------------------------------------------

void FTexture::CheckTrans(unsigned char * buffer, int size, int trans)
{
	if (bTranslucent == -1)
	{
		bTranslucent = trans;
		if (trans == -1)
		{
			uint32_t * dwbuf = (uint32_t*)buffer;
			for (int i = 0; i<size; i++)
			{
				uint32_t alpha = dwbuf[i] >> 24;

				if (alpha != 0xff && alpha != 0)
				{
					bTranslucent = 1;
					return;
				}
			}
			bTranslucent = 0;
		}
	}
}


//===========================================================================
// 
// smooth the edges of transparent fields in the texture
//
//===========================================================================

#ifdef WORDS_BIGENDIAN
#define MSB 0
#define SOME_MASK 0xffffff00
#else
#define MSB 3
#define SOME_MASK 0x00ffffff
#endif

#define CHKPIX(ofs) (l1[(ofs)*4+MSB]==255 ? (( ((uint32_t*)l1)[0] = ((uint32_t*)l1)[ofs]&SOME_MASK), trans=true ) : false)

bool FTexture::SmoothEdges(unsigned char * buffer, int w, int h)
{
	int x, y;
	bool trans = buffer[MSB] == 0; // If I set this to false here the code won't detect textures 
								   // that only contain transparent pixels.
	bool semitrans = false;
	unsigned char * l1;

	if (h <= 1 || w <= 1) return false;  // makes (a) no sense and (b) doesn't work with this code!

	l1 = buffer;


	if (l1[MSB] == 0 && !CHKPIX(1)) CHKPIX(w);
	else if (l1[MSB]<255) semitrans = true;
	l1 += 4;
	for (x = 1; x<w - 1; x++, l1 += 4)
	{
		if (l1[MSB] == 0 && !CHKPIX(-1) && !CHKPIX(1)) CHKPIX(w);
		else if (l1[MSB]<255) semitrans = true;
	}
	if (l1[MSB] == 0 && !CHKPIX(-1)) CHKPIX(w);
	else if (l1[MSB]<255) semitrans = true;
	l1 += 4;

	for (y = 1; y<h - 1; y++)
	{
		if (l1[MSB] == 0 && !CHKPIX(-w) && !CHKPIX(1)) CHKPIX(w);
		else if (l1[MSB]<255) semitrans = true;
		l1 += 4;
		for (x = 1; x<w - 1; x++, l1 += 4)
		{
			if (l1[MSB] == 0 && !CHKPIX(-w) && !CHKPIX(-1) && !CHKPIX(1) && !CHKPIX(-w - 1) && !CHKPIX(-w + 1) && !CHKPIX(w - 1) && !CHKPIX(w + 1)) CHKPIX(w);
			else if (l1[MSB]<255) semitrans = true;
		}
		if (l1[MSB] == 0 && !CHKPIX(-w) && !CHKPIX(-1)) CHKPIX(w);
		else if (l1[MSB]<255) semitrans = true;
		l1 += 4;
	}

	if (l1[MSB] == 0 && !CHKPIX(-w)) CHKPIX(1);
	else if (l1[MSB]<255) semitrans = true;
	l1 += 4;
	for (x = 1; x<w - 1; x++, l1 += 4)
	{
		if (l1[MSB] == 0 && !CHKPIX(-w) && !CHKPIX(-1)) CHKPIX(1);
		else if (l1[MSB]<255) semitrans = true;
	}
	if (l1[MSB] == 0 && !CHKPIX(-w)) CHKPIX(-1);
	else if (l1[MSB]<255) semitrans = true;

	return trans || semitrans;
}

//===========================================================================
// 
// Post-process the texture data after the buffer has been created
//
//===========================================================================

bool FTexture::ProcessData(unsigned char * buffer, int w, int h, bool ispatch)
{
	if (bMasked)
	{
		bMasked = SmoothEdges(buffer, w, h);
		if (bMasked && !ispatch) FindHoles(buffer, w, h);
	}
	return true;
}

//===========================================================================
// 
//	Initializes the buffer for the texture data
//
//===========================================================================

FTextureBuffer FTexture::CreateTexBuffer(int translation, int flags)
{
	FTextureBuffer result;

	unsigned char * buffer = nullptr;
	int W, H;
	int isTransparent = -1;
	bool checkonly = !!(flags & CTF_CheckOnly);

	if (flags & CTF_CheckHires)
	{
		// No image means that this cannot be checked,
		if (GetImage() && LoadHiresTexture(result, checkonly)) return result;
	}
	int exx = !!(flags & CTF_Expand);

	W = GetWidth() + 2 * exx;
	H = GetHeight() + 2 * exx;

	if (!checkonly)
	{
		buffer = new unsigned char[W*(H + 1) * 4];
		memset(buffer, 0, W * (H + 1) * 4);

		auto remap = translation <= 0 ? nullptr : FUniquePalette::GetPalette(translation);
		FBitmap bmp(buffer, W * 4, W, H);

		int trans;
		auto Pixels = GetBgraBitmap(remap, &trans);
		bmp.Blit(exx, exx, Pixels);

		if (remap == nullptr)
		{
			CheckTrans(buffer, W*H, trans);
			isTransparent = bTranslucent;
		}
		else
		{
			isTransparent = 0;
			// A translated image is not conclusive for setting the texture's transparency info.
		}
	}

	if (GetImage())
	{
		FContentIdBuilder builder;
		builder.id = 0;
		builder.imageID = GetImage()->GetId();
		builder.translation = MAX(0, translation);
		builder.expand = exx;
		result.mContentId = builder.id;
	}
	else result.mContentId = 0;	// for non-image backed textures this has no meaning so leave it at 0.

	result.mBuffer = buffer;
	result.mWidth = W;
	result.mHeight = H;

	// Only do postprocessing for image-backed textures. (i.e. not for the burn texture which can also pass through here.)
	if (GetImage() && flags & CTF_ProcessData) 
	{
		CreateUpsampledTextureBuffer(result, !!isTransparent, checkonly);
		if (!checkonly) ProcessData(result.mBuffer, result.mWidth, result.mHeight, false);
	}

	return result;
}

//===========================================================================
// 
// Dummy texture for the 0-entry.
//
//===========================================================================

bool FTexture::GetTranslucency()
{
	if (bTranslucent == -1)
	{
		if (!bHasCanvas)
		{
			// This will calculate all we need, so just discard the result.
			CreateTexBuffer(0);
		}
		else
		{
			bTranslucent = 0;
		}
	}
	return !!bTranslucent;
}

//===========================================================================
// 
// Sprite adjust has changed.
// This needs to alter the material's sprite rect.
//
//===========================================================================

void FTexture::SetSpriteAdjust()
{
	for (auto mat : Material)
	{
		if (mat != nullptr) mat->SetSpriteRect();
	}
}

//===========================================================================
// 
// the default just returns an empty texture.
//
//===========================================================================

TArray<uint8_t> FTexture::Get8BitPixels(bool alphatex)
{
	TArray<uint8_t> Pixels(Width * Height, true);
	memset(Pixels.Data(), 0, Width * Height);
	return Pixels;
}

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

FWrapperTexture::FWrapperTexture(int w, int h, int bits)
{
	Width = w;
	Height = h;
	Format = bits;
	UseType = ETextureType::SWCanvas;
	bNoCompress = true;
	auto hwtex = screen->CreateHardwareTexture();
	// todo: Initialize here.
	SystemTextures.AddHardwareTexture(0, false, hwtex);
}

//===========================================================================
//
// Coordinate helper.
// The only reason this is even needed is that many years ago someone
// was convinced that having per-texel panning on walls was a good idea.
// If it wasn't for this relatively useless feature the entire positioning
// code for wall textures could be a lot simpler.
//
//===========================================================================

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

float FTexCoordInfo::RowOffset(float rowoffset) const
{
	float scale = fabs(mScale.Y);
	if (scale == 1.f || mWorldPanning) return rowoffset;
	else return rowoffset / scale;
}

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

float FTexCoordInfo::TextureOffset(float textureoffset) const
{
	float scale = fabs(mScale.X);
	if (scale == 1.f || mWorldPanning) return textureoffset;
	else return textureoffset / scale;
}

//===========================================================================
//
// Returns the size for which texture offset coordinates are used.
//
//===========================================================================

float FTexCoordInfo::TextureAdjustWidth() const
{
	if (mWorldPanning)
	{
		float tscale = fabs(mTempScale.X);
		if (tscale == 1.f) return (float)mRenderWidth;
		else return mWidth / fabs(tscale);
	}
	else return (float)mWidth;
}


//===========================================================================
//
// Retrieve texture coordinate info for per-wall scaling
//
//===========================================================================

void FTexCoordInfo::GetFromTexture(FTexture *tex, float x, float y)
{
	if (x == 1.f)
	{
		mRenderWidth = tex->GetScaledWidth();
		mScale.X = (float)tex->Scale.X;
		mTempScale.X = 1.f;
	}
	else
	{
		float scale_x = x * (float)tex->Scale.X;
		mRenderWidth = xs_CeilToInt(tex->GetWidth() / scale_x);
		mScale.X = scale_x;
		mTempScale.X = x;
	}

	if (y == 1.f)
	{
		mRenderHeight = tex->GetScaledHeight();
		mScale.Y = (float)tex->Scale.Y;
		mTempScale.Y = 1.f;
	}
	else
	{
		float scale_y = y * (float)tex->Scale.Y;
		mRenderHeight = xs_CeilToInt(tex->GetHeight() / scale_y);
		mScale.Y = scale_y;
		mTempScale.Y = y;
	}
	if (tex->bHasCanvas)
	{
		mScale.Y = -mScale.Y;
		mRenderHeight = -mRenderHeight;
	}
	mWorldPanning = tex->bWorldPanning || (level.flags3 & LEVEL3_FORCEWORLDPANNING);
	mWidth = tex->GetWidth();
}