shithub: tinygl

ref: c99b80721b808a9475068a8eafde9b7c3cac679e
dir: /src/zline.c/

#include <stdlib.h>
#include "../include/zbuffer.h"

#define ZCMP(z,zpix) ((z) >= (zpix))

void ZB_plot(ZBuffer * zb, ZBufferPoint * p)
{
    GLushort *pz;
    PIXEL *pp;
    GLint zz;
	#if TGL_FEATURE_NO_DRAW_COLOR == 1
	PIXEL col;
	#endif
    pz = zb->zbuf + (p->y * zb->xsize + p->x);
    pp = (PIXEL *) ((GLbyte *) zb->pbuf + zb->linesize * p->y + p->x * PSZB);
    zz = p->z >> ZB_POINT_Z_FRAC_BITS;
    if (ZCMP(zz, *pz)) {
//#if TGL_FEATURE_RENDER_BITS == 24 
        //pp[0]=p->r>>8;
        //pp[1]=p->g>>8;
        //pp[2]=p->b>>8;
//#else
#if TGL_FEATURE_NO_DRAW_COLOR == 1
#define NODRAWTEST(color) ( (color & TGL_COLOR_MASK) != TGL_NO_DRAW_COLOR)
		col = RGB_TO_PIXEL(p->r, p->g, p->b);
		if(NODRAWTEST(col))
			*pp = RGB_TO_PIXEL(p->r, p->g, p->b);
#else
		*pp = RGB_TO_PIXEL(p->r, p->g, p->b);
#endif
//#endif
	*pz = zz;
    }
}

#define INTERP_Z
static void ZB_line_flat_z(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2, 
                           GLint color)
{
#include "zline.h"
}

/* line with color GLinterpolation */
#define INTERP_Z
#define INTERP_RGB
static void ZB_line_interp_z(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2)
{
#include "zline.h"
}

/* no Z GLinterpolation */

static void ZB_line_flat(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2, 
                             GLint color)
{
#include "zline.h"
}

#define INTERP_RGB
static void ZB_line_interp(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2)
{
#include "zline.h"
}

void ZB_line_z(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2)
{
    GLint color1, color2;

    color1 = RGB_TO_PIXEL(p1->r, p1->g, p1->b);
    color2 = RGB_TO_PIXEL(p2->r, p2->g, p2->b);

    /* choose if the line should have its color GLinterpolated or not */
    if (color1 == color2) {
        ZB_line_flat_z(zb, p1, p2, color1);
    } else {
        ZB_line_interp_z(zb, p1, p2);
    }
}

void ZB_line(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2)
{
    GLint color1, color2;

    color1 = RGB_TO_PIXEL(p1->r, p1->g, p1->b);
    color2 = RGB_TO_PIXEL(p2->r, p2->g, p2->b);

    /* choose if the line should have its color GLinterpolated or not */
    if (color1 == color2) {
        ZB_line_flat(zb, p1, p2, color1);
    } else {
        ZB_line_interp(zb, p1, p2);
    }
}