r_patch.h

// Emacs style mode select   -*- C++ -*- 
//-----------------------------------------------------------------------------
//
// Copyright(C) 2010 James Haley
//
// This program 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.
// 
// This program 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 this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//
//--------------------------------------------------------------------------
//
// DESCRIPTION:
//
// Patches.
// A patch holds one or more columns. Patches are used for sprites and all 
// masked pictures, and we compose textures from the TEXTURE1/2 lists of 
// patches.
//
// haleyjd 11/21/10: Separated from r_defs.h to help resolve circular
// #include dependency problems.
//
//-----------------------------------------------------------------------------

#ifndef R_PATCH_H__
#define R_PATCH_H__

// Required for: byte, stdint types
#include "doomtype.h"

#if defined(_MSC_VER) || defined(__GNUC__)
#pragma pack(push, 1)
#endif

// posts are runs of non masked source pixels
struct post_t
{
   byte topdelta; // -1 is the last post in a column
   byte length;   // length data bytes follows
};

// column_t is a list of 0 or more post_t, (byte)-1 terminated
typedef post_t column_t;

struct patch_t
{ 
   int16_t width, height;  // bounding box size 
   int16_t leftoffset;     // pixels to the left of origin 
   int16_t topoffset;      // pixels below the origin 
   int32_t columnofs[8];   // only [width] used
};

#if defined(_MSC_VER) || defined(__GNUC__)
#pragma pack(pop)
#endif

#endif

// EOF