ref: 50fc39b242e889b7bec9971acb1f8438e29095f5
dir: /include/zbuffer.h/
#ifndef _tgl_zbuffer_h_
#define _tgl_zbuffer_h_
/*
* Z buffer
*/
#include "zfeatures.h"
#include "GL/gl.h"
//#warning stdio is left in!!! remove it!!!
//#include <stdio.h>
#define ZB_Z_BITS 16
#define ZB_POINT_Z_FRAC_BITS 14
//a "1" in bit FRAC_BITS+1 (starting at zero) = 1.
//This is a complicated as hell fixed point math standard.
//go to zfeatures.h to find out how this stuff is decided
#define ZB_POINT_S_MIN ( (1<<ZB_POINT_S_FRAC_BITS) )
#define ZB_POINT_S_MAX ( (1<<(1+TGL_FEATURE_TEXTURE_POW2+ZB_POINT_S_FRAC_BITS))-ZB_POINT_S_MIN )
#define ZB_POINT_T_MIN ( (1<<ZB_POINT_T_FRAC_BITS) )
#define ZB_POINT_T_MAX ( (1<<(1+TGL_FEATURE_TEXTURE_POW2+ZB_POINT_T_FRAC_BITS))-ZB_POINT_T_MIN )
#define ZB_POINT_S_VALUE (ZB_POINT_S_FRAC_BITS + 4)
#define ZB_POINT_T_VALUE (ZB_POINT_T_FRAC_BITS - 4)
#define ZB_S_MASK ((TGL_FEATURE_TEXTURE_DIM-1)<<(ZB_POINT_S_FRAC_BITS+1))
#define ZB_T_MASK ((TGL_FEATURE_TEXTURE_DIM-1)<<(ZB_POINT_T_FRAC_BITS+1))
//PSZSH is 5 at 32 bit, or 4 at 16 bit.
#if ZB_POINT_T_FRAC_BITS == (ZB_POINT_S_FRAC_BITS + TGL_FEATURE_TEXTURE_POW2)
#define ST_TO_TEXTURE_BYTE_OFFSET(s,t) ( ((s & ZB_S_MASK) | (t & ZB_T_MASK)) >> (ZB_POINT_S_VALUE-PSZSH))
#else
#define ST_TO_TEXTURE_BYTE_OFFSET(s,t) ( ((s & ZB_S_MASK)>>(ZB_POINT_S_VALUE-PSZSH)) | ((t & ZB_T_MASK)>>(ZB_POINT_T_VALUE-PSZSH)) )
#endif
//This is how textures are sampled. if you want to do some sort of fancy texture filtering,
//you do it here.
#define TEXTURE_SAMPLE(texture, s, t) \
(*(PIXEL*)( (GLbyte*)texture + \
ST_TO_TEXTURE_BYTE_OFFSET(s,t) \
))
/* display modes */
#define ZB_MODE_5R6G5B 1 /* true color 16 bits */
#define ZB_MODE_INDEX 2 /* color index 8 bits */
#define ZB_MODE_RGBA 3 /* 32 bit ABGR mode */
#define ZB_MODE_RGB24 4 /* 24 bit rgb mode */
#define ZB_NB_COLORS 225 /* number of colors for 8 bit display */
#if TGL_FEATURE_RENDER_BITS == 32
/* 32 bit mode */
//#define RGB_TO_PIXEL(r,g,b) ( ((b&65280)<<8) | ((g&65280)) | ((r&65280)>>8) )
#define RGB_TO_PIXEL(r,g,b) \
((((r) << 8) & 0xff0000) | ((g) & 0xff00) | ((b) >> 8))
#define GET_RED(p) ((p & 0xff0000)>>16)
#define GET_REDDER(p) ((p & 0xff0000)>>8)
#define GET_GREEN(p) ((p & 0xff00)>>8)
#define GET_GREENER(p) ((p & 0xff00))
#define GET_BLUE(p) (p & 0xff)
#define GET_BLUEER(p) ((p & 0xff)<<8)
typedef GLuint PIXEL;
#define PSZB 4
#define PSZSH 5
#elif TGL_FEATURE_RENDER_BITS == 16
/* 16 bit mode */
#define RGB_TO_PIXEL(r,g,b) (((r) & 0xF800) | (((g) >> 5) & 0x07E0) | ((b) >> 11))
#define GET_RED(p) ((p & 0xF800)>>8)
#define GET_REDDER(p) ((p & 0xF800))
#define GET_GREEN(p) ((p & 0x07E0)>>3)
#define GET_GREENER(p) ((p & 0x07E0)<<5)
#define GET_BLUE(p) ((p & 31)<<3)
#define GET_BLUEER(p) ((p & 31)<<11)
typedef GLushort PIXEL;
#define PSZB 2
#define PSZSH 4
#else
#error "wrong TGL_FEATURE_RENDER_BITS buddy"
#endif
#if TGL_FEATURE_LIT_TEXTURES == 1
#define RGB_MIX_FUNC(rr, gg, bb, tpix) \
RGB_TO_PIXEL( \
((rr * GET_RED(tpix))>>8),\
((gg * GET_GREEN(tpix))>>8),\
((bb * GET_BLUE(tpix))>>8)\
)
#else
#define RGB_MIX_FUNC(rr, gg, bb, tpix)(tpix)
#endif
#if TGL_FEATURE_BLEND == 1
#define TGL_BLEND_VARS GLuint zbblendeq = zb->blendeq; GLuint sfactor = zb->sfactor; GLuint dfactor = zb->dfactor;
#define TGL_NO_BLEND_FUNC(source, dest){dest = source;}
#define TGL_NO_BLEND_FUNC_RGB(rr, gg, bb, dest){dest = RGB_TO_PIXEL(rr,gg,bb);}
//SORCERY to achieve 32 bit signed integer clamping
#define TGL_CLAMPI(imp) ( (imp>0) * (65535 * (imp>65535) + imp * (!(imp>65535)) ) )
#define TGL_BLEND_SWITCH_CASE(sr,sg,sb,dr,dg,db,dest) \
switch(zbblendeq){ \
case GL_FUNC_ADD: \
default: \
sr+=dr;sg+=dg;sb+=db; \
sr = TGL_CLAMPI(sr); \
sg = TGL_CLAMPI(sg); \
sb = TGL_CLAMPI(sb); \
dest = RGB_TO_PIXEL(sr,sg,sb); \
break; \
case GL_FUNC_SUBTRACT: \
sr-=dr;sg-=dg;sb-=db; \
sr = TGL_CLAMPI(sr); \
sg = TGL_CLAMPI(sg); \
sb = TGL_CLAMPI(sb); \
dest = RGB_TO_PIXEL(sr,sg,sb); \
break; \
case GL_FUNC_REVERSE_SUBTRACT: \
sr=dr-sr;sg=dg-sg;sb=db-sb; \
sr = TGL_CLAMPI(sr); \
sg = TGL_CLAMPI(sg); \
sb = TGL_CLAMPI(sb); \
dest = RGB_TO_PIXEL(sr,sg,sb); \
break; \
\
}
#define TGL_BLEND_FUNC(source, dest){ \
{ \
GLuint sr, sg, sb, dr, dg, db; \
{ GLuint t = source; \
sr = GET_REDDER(t); sg = GET_GREENER(t); sb = GET_BLUEER(t); \
t = dest; \
dr = GET_REDDER(t); dg = GET_GREENER(t); db = GET_BLUEER(t);} \
/*printf("\nShould never reach this point!");*/ \
switch(sfactor){ \
case GL_ONE: \
default: \
break; \
case GL_ONE_MINUS_SRC_COLOR: \
sr = ~sr & 0xffff; \
sg = ~sg & 0xffff; \
sb = ~sb & 0xffff; \
break; \
case GL_ZERO: \
sr=0;sg=0;sb=0;break; \
break; \
} \
switch(dfactor){ \
case GL_ONE: \
default: \
break; \
case GL_ONE_MINUS_DST_COLOR: \
dr = ~dr & 0xffff; \
dg = ~dg & 0xffff; \
db = ~db & 0xffff; \
break; \
case GL_ZERO: \
dr=0;dg=0;db=0;break; \
break; \
} \
TGL_BLEND_SWITCH_CASE(sr,sg,sb,dr,dg,db,dest) \
} \
} ///////////////////////////////////////////////////////////////////////////////////////
#define TGL_BLEND_FUNC_RGB(rr, gg, bb, dest){ \
{ \
GLint sr = rr & 0xFFFF, sg = gg & 0xFFFF, sb = bb & 0xFFFF, dr, dg, db; \
{GLuint t = dest; \
dr = GET_REDDER(t); dg = GET_GREENER(t); db = GET_BLUEER(t);} \
/*printf("\nShould never reach this point!");*/ \
switch(sfactor){ \
case GL_ONE: \
default: \
break; \
case GL_ONE_MINUS_SRC_COLOR: \
sr = ~sr & 0xffff; \
sg = ~sg & 0xffff; \
sb = ~sb & 0xffff; \
break; \
case GL_ZERO: \
sr=0;sg=0;sb=0;break; \
break; \
} \
switch(dfactor){ \
case GL_ONE: \
default: \
break; \
case GL_ONE_MINUS_DST_COLOR: \
dr = ~dr & 0xffff; \
dg = ~dg & 0xffff; \
db = ~db & 0xffff; \
break; \
case GL_ZERO: \
dr=0;dg=0;db=0;break; \
break; \
} \
TGL_BLEND_SWITCH_CASE(sr,sg,sb,dr,dg,db,dest) \
} \
} ///////////////////////////////////////////////////////////////////////////////////////
#else
#define TGL_BLEND_VARS /* a comment */
#define TGL_BLEND_FUNC(source, dest){dest = source;}
#define TGL_BLEND_FUNC_RGB(rr, gg, bb, dest){dest = RGB_TO_PIXEL(rr,gg,bb);}
#endif
typedef struct {
GLint xsize,ysize;
GLint linesize; /* line size, in bytes */
GLint mode;
GLushort *zbuf;
PIXEL *pbuf;
GLint frame_buffer_allocated;
/* depth */
GLint depth_test;
GLint depth_write;
/* point size*/
GLfloat pointsize;
// GLint nb_colors;
// unsigned char *dctable;
// GLint *ctable;
PIXEL *current_texture;
/* opengl polygon stipple*/
#if TGL_FEATURE_POLYGON_STIPPLE == 1
GLubyte stipplepattern[TGL_POLYGON_STIPPLE_BYTES];
GLuint dostipple;
#endif
GLenum blendeq, sfactor, dfactor;
GLint enable_blend;
} ZBuffer;
typedef struct {
GLint x,y,z; /* integer coordinates in the zbuffer */
GLint s,t; /* coordinates for the mapping */
GLint r,g,b; /* color indexes */
GLfloat sz,tz; /* temporary coordinates for mapping */
} ZBufferPoint;
/* zbuffer.c */
ZBuffer *ZB_open(int xsize,int ysize,int mode,
// GLint nb_colors,
// unsigned char *color_indexes,
// GLint *color_table,
void *frame_buffer);
void ZB_close(ZBuffer *zb);
void ZB_resize(ZBuffer *zb,void *frame_buffer,GLint xsize,GLint ysize);
void ZB_clear(ZBuffer *zb,GLint clear_z,GLint z,
GLint clear_color,GLint r,GLint g,GLint b);
/* linesize is in BYTES */
void ZB_copyFrameBuffer(ZBuffer *zb,void *buf,GLint linesize);
/* zdither.c */
/*
void ZB_initDither(ZBuffer *zb,GLint nb_colors,
unsigned char *color_indexes,GLint *color_table);
void ZB_closeDither(ZBuffer *zb);
void ZB_ditherFrameBuffer(ZBuffer *zb,unsigned char *dest,
GLint linesize);
*/
/* zline.c */
void ZB_plot(ZBuffer *zb,ZBufferPoint *p);
void ZB_line(ZBuffer *zb,ZBufferPoint *p1,ZBufferPoint *p2);
void ZB_line_z(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2);
/* ztriangle.c */
void ZB_setTexture(ZBuffer *zb, PIXEL *texture);
void ZB_fillTriangleFlat(ZBuffer *zb,
ZBufferPoint *p1,ZBufferPoint *p2,ZBufferPoint *p3);
void ZB_fillTriangleFlatNOBLEND(ZBuffer *zb,
ZBufferPoint *p1,ZBufferPoint *p2,ZBufferPoint *p3);
void ZB_fillTriangleSmooth(ZBuffer *zb,
ZBufferPoint *p1,ZBufferPoint *p2,ZBufferPoint *p3);
void ZB_fillTriangleSmoothNOBLEND(ZBuffer *zb,
ZBufferPoint *p1,ZBufferPoint *p2,ZBufferPoint *p3);
/*
This function goes unused and is removed by Gek.
void ZB_fillTriangleMapping(ZBuffer *zb,
ZBufferPoint *p1,ZBufferPoint *p2,ZBufferPoint *p3);
*/
void ZB_fillTriangleMappingPerspective(ZBuffer *zb,
ZBufferPoint *p0,ZBufferPoint *p1,ZBufferPoint *p2);
void ZB_fillTriangleMappingPerspectiveNOBLEND(ZBuffer *zb,
ZBufferPoint *p0,ZBufferPoint *p1,ZBufferPoint *p2);
typedef void (*ZB_fillTriangleFunc)(ZBuffer *,
ZBufferPoint *,ZBufferPoint *,ZBufferPoint *);
/* memory.c */
void gl_free(void *p);
void *gl_malloc(GLint size);
void *gl_zalloc(GLint size);
void gl_memcpy(void* dest, void* src, GLuint size);
#endif /* _tgl_zbuffer_h_ */