raze-gles/source/common/textures/imagehelpers.h
2019-10-14 23:11:01 +02:00

145 lines
4.2 KiB
C++

#pragma once
/*
** imagehelpers.h
** Utilities for image conversion - mostly 8 bit paletted baggage
**
**---------------------------------------------------------------------------
** 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 <stdint.h>
#include "tarray.h"
#include "palentry.h"
#include "textures/bitmap.h"
namespace ImageHelpers
{
union ColorTable256k
{
uint8_t RGB[64][64][64];
uint8_t All[64 * 64 * 64];
};
extern uint8_t GrayMap[256];
extern PalEntry BaseColors[256];
extern PalEntry BasePalette[256]; // same as above, but with a being a proper alpha channel.
extern int WhiteIndex, BlackIndex;
extern ColorTable256k RGB256k;
extern int alphaThreshold;
// Todo: This should not pick fullbright colors.
int BestColor(int r, int g, int b, int first = 0, int num = 255);
void SetPalette(const PalEntry* colors);
// Helpers for creating paletted images.
inline uint8_t *GetGraymap()
{
return GrayMap;
}
inline uint8_t RGBToPalettePrecise(bool wantluminance, int r, int g, int b, int a = 255)
{
return BestColor(r, g, b);
}
inline uint8_t RGBToPalette(bool wantluminance, int r, int g, int b, int a = 255)
{
return a < alphaThreshold? 255 : RGB256k.RGB[r >> 2][g >> 2][b >> 2];
}
inline uint8_t RGBToPalette(bool wantluminance, PalEntry pe, bool hasalpha = true)
{
return RGBToPalette(wantluminance, pe.r, pe.g, pe.b, hasalpha? pe.a : 255);
}
//==========================================================================
//
// Converts a texture between row-major and column-major format
// by flipping it about the X=Y axis.
//
//==========================================================================
template<class T>
void FlipSquareBlock (T *block, int x)
{
for (int i = 0; i < x; ++i)
{
T *corner = block + x*i + i;
int count = x - i;
for (int j = 0; j < count; j++)
{
std::swap(corner[j], corner[j*x]);
}
}
}
inline void FlipSquareBlockRemap (uint8_t *block, int x, const uint8_t *remap)
{
for (int i = 0; i < x; ++i)
{
uint8_t *corner = block + x*i + i;
int count = x - i;
for (int j = 0; j < count; j++)
{
auto t = remap[corner[j]];
corner[j] = remap[corner[j*x]];
corner[j*x] = t;
}
}
}
template<class T>
void FlipNonSquareBlock (T *dst, const T *src, int x, int y, int srcpitch)
{
for (int i = 0; i < x; ++i)
{
for (int j = 0; j < y; ++j)
{
dst[i*y+j] = src[i+j*srcpitch];
}
}
}
inline void FlipNonSquareBlockRemap (uint8_t *dst, const uint8_t *src, int x, int y, int srcpitch, const uint8_t *remap)
{
for (int i = 0; i < x; ++i)
{
for (int j = 0; j < y; ++j)
{
dst[i*y+j] = remap[src[i+j*srcpitch]];
}
}
}
}