genfunc.c

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}

/* Draw a horizontal line from x1 to and including x2 in the
 * foreground color, applying clipping if necessary.
 */
static void drawrow(PSD psd, int x1, int x2, int y)
{
	int temp;
	/* reverse endpoints if necessary*/
	if (x1 > x2) {
		temp = x1;
		x1 = x2;
		x2 = temp;
	}

	/* clip to physical device*/
	if ( psd->doclip) {
		if ( (x2 < psd->clipminx) || ( x1 >= psd->clipmaxx) )
			return;
		if ( (y < psd->clipminy) || (y >= psd->clipmaxy) )
			  return;
		if (x2 < psd->clipminx)
			  return ;
		if (x1 >= psd->clipmaxx)
			  return;

		if (x1 < psd->clipminx)
			  x1 = psd->clipminx;
		if (x2 >= psd->clipmaxx)
			  x2 = psd->clipmaxx - 1;
	} else {
		if ( (x2 < 0) || ( x1 >= psd->xres) )
			return;
		if ( (y < 0) || (y >= psd->yres) )
			  return;
		if (x1 < 0)
			  x1 = 0;
		if (x2 >= psd->xres)
			  x2 = psd->xres - 1;
	}
	psd->DrawHLine(psd, x1, y, x2-x1+1, psd->gr_foreground);
}

/* 
 * Draw a vertical line from y1 to and including y2 in the
 * foreground color, applying clipping if necessary.
 */
static void drawcol(PSD psd, int x,int y1,int y2)
{
	int temp;

	/* reverse endpoints if necessary*/
	if (y1 > y2) {
		temp = y1;
		y1 = y2;
		y2 = temp;
	}

	/* clip to physical device*/
	if ( psd->doclip) {
		if ( (x < psd->clipminx) || ( x >= psd->clipmaxx) )
			return;
		if ( (y2 < psd->clipminy) || (y1 >= psd->clipmaxy) )
			  return;

		if (y1 < psd->clipminy)
			  y1 = psd->clipminy;
		if (y2 >= psd->clipmaxy)
			  y2 = psd->clipmaxy - 1;
	} else {
		if ( (x < 0) || ( x >= psd->xres) )
			return;
		if ( (y2 < 0) || (y1 >= psd->yres) )
			return;
		if (y1 < 0)
			  y1 = 0;
		if (y2 >= psd->yres)
			  y2 = psd->yres - 1;
	}

	psd->DrawVLine(psd, x, y1, y2-y1+1, psd->gr_foreground);
}

#if 0
void generate_palette(GAL_Color *pal, int num)
{
	GAL_Color black  = { 0, 0, 0, 0 };
	GAL_Color white  = { 255, 255, 255, 0 };
	GAL_Color blue   = { 0, 0, 255, 0 };
	GAL_Color yellow = { 255, 255, 0, 0 };

	int i, depth, N;

	int rnum,  gnum,  bnum;
	int rmask, gmask, bmask;
	
	/* handle small palettes */

	if (num == 0) return;

	pal[0] = black;   if (num == 1) return;
	pal[1] = white;   if (num == 2) return;
	pal[2] = blue;    if (num == 3) return;
	pal[3] = yellow;  if (num == 4) return;

	/* handle large palettes. */

	depth = 0;  /* work out depth so that (1 << depth) >= num */

	for (N = num-1; N > 0; N /= 2) {
		depth++;
	}

	gnum = (depth + 2) / 3;  /* green has highest priority */
	rnum = (depth + 1) / 3;  /* red has second highest priority */
	bnum = (depth + 0) / 3;  /* blue has lowest priority */

	gmask = (1 << gnum) - 1;
	rmask = (1 << rnum) - 1;
	bmask = (1 << bnum) - 1;

	for (i=0; i < num; i++) {

		/* When num < (1 << depth), we interpolate the values so
		 * that we still get a good range.  There's probably a
		 * better way...
		 */
		
		int j = i * ((1 << depth) - 1) / (num - 1);
		int r, g, b;
		
		b = j & bmask;  j >>= bnum;
		r = j & rmask;  j >>= rnum;
		g = j & gmask;

		pal[i].r = r * 0xffff / rmask;
		pal[i].g = g * 0xffff / gmask;
		pal[i].b = b * 0xffff / bmask;
		pal[i].a = 0;
	}
}
#endif
//==================draw a circle =====================================

static inline void setpixel(PSD psd, int x, int y, int c)
{
	if( psd->ClipPoint (psd, x, y))
		psd->DrawPixel(psd, x, y, c);
}

		
			
static void setcirclepixels(PSD psd, int x, int y, int sx, int sy, int c)
{
	if ( psd->doclip ) {
		int z = MAX (x, y);
		if (sx - z < psd->clipminx || sx + z >= psd->clipmaxx || sy - z < psd->clipminy || sy + z >= psd->clipmaxy) {
		    	/* use setpixel clipping */
			setpixel(psd, sx + x, sy + y, c);
			setpixel(psd, sx - x, sy + y, c);
			setpixel(psd, sx + x, sy - y, c);
			setpixel(psd, sx - x, sy - y, c);
			setpixel(psd, sx + y, sy + x, c);
		 	setpixel(psd, sx - y, sy + x, c);
			setpixel(psd, sx + y, sy - x, c);
			setpixel(psd, sx - y, sy - x, c);
			return;
		}
	}
	psd->DrawPixel(psd, sx + x, sy + y, c);
	psd->DrawPixel(psd, sx - x, sy + y, c);
	psd->DrawPixel(psd, sx + x, sy - y, c);
	psd->DrawPixel(psd, sx - x, sy - y, c);
	psd->DrawPixel(psd, sx + y, sy + x, c);
	psd->DrawPixel(psd, sx - y, sy + x, c);
	psd->DrawPixel(psd, sx + y, sy - x, c);
	psd->DrawPixel(psd, sx - y, sy - x, c);
}

void native_gen_circle(PSD psd, int sx, int sy, int r, int c)
{
	int x, y, d;

	if (r < 1) {
		setpixel(psd, sx, sy, c);
		return;
	}

	if (psd->doclip){
		if (sx + r < psd->clipminx) return;
		if (sx - r >= psd->clipmaxx) return; 
		if (sy + r < psd->clipminy) return;
		if (sy - r >= psd->clipmaxy) return; 
	}

	x = 0;
	y = r;
	d = 1 - r;

	setcirclepixels(psd, x, y, sx, sy, c);
	while (x < y) {
		if (d < 0)
		    d += x * 2 + 3;
		else {
		    d += x * 2 - y * 2 + 5;
		    y--;
		}
		x++;
		setcirclepixels(psd, x, y, sx, sy, c);
	}
}

//=================================scale box =================================================
/*      scalebox comes from SVGALib, Copyright 1993 Harm Hanemaayer         */
typedef unsigned char uchar;

/* We use the 32-bit to 64-bit multiply and 64-bit to 32-bit divide of the */
/* 386 (which gcc doesn't know well enough) to efficiently perform integer */
/* scaling without having to worry about overflows. */
#ifdef USE_ASM
static inline int muldiv64(int m1, int m2, int d)
{
/* int32 * int32 -> int64 / int32 -> int32 */
    int result;
    __asm__(
           "imull %%edx\n\t"
           "idivl %3\n\t"
  :           "=a"(result)    /* out */
  :           "a"(m1), "d"(m2), "g"(d)        /* in */
  :           "ax", "dx"    /* mod */
    );
    return result;
}
#else
static inline int muldiv64 (int m1, int m2, int d)
{
    long long int mul = (long long int) m1 * m2;

    return (int) (mul / d);
}

#endif

/* This is a DDA-based algorithm. */
/* Iteration over target bitmap. */
int native_gen_scalebox (PSD psd, int w1, int h1, void *_dp1, int w2, int h2, void *_dp2)
{
    uchar *dp1 = _dp1;
    uchar *dp2 = _dp2;
    int xfactor;
    int yfactor;

    if (w2 == 0 || h2 == 0)
        return 0;

    xfactor = muldiv64(w1, 65536, w2);        /* scaled by 65536 */
    yfactor = muldiv64(h1, 65536, h2);        /* scaled by 65536 */

    switch ((psd->bpp + 7) / 8) {
    case 1:
        {
            int y, sy;
            sy = 0;
            for (y = 0; y < h2;) {
                int sx = 0;
                uchar *dp2old = dp2;
                int x;
                x = 0;
                while (x < w2 - 8) {
#ifdef USE_ASM

                    /* This saves just a couple of cycles per */
                    /* pixel on a 486, but I couldn't resist. */
                    __asm__ __volatile__("movl %4, %%eax\n\t"
                                         "shrl $16, %%eax\n\t"
                                         "addl %5, %4\n\t"
                                         "movb (%3, %%eax), %%al\n\t"
                                         "movb %%al, (%1, %2)\n\t"
                                         "movl %4, %%eax\n\t"
                                         "shrl $16, %%eax\n\t"
                                         "addl %5, %4\n\t"
                                         "movb (%3, %%eax), %%al\n\t"
                                         "movb %%al, 1 (%1, %2)\n\t"
                                         "movl %4, %%eax\n\t"
                                         "shrl $16, %%eax\n\t"
                                         "addl %5, %4\n\t"
                                         "movb (%3, %%eax), %%al\n\t"
                                         "movb %%al, 2 (%1, %2)\n\t"
                                         "movl %4, %%eax\n\t"
                                         "shrl $16, %%eax\n\t"
                                         "addl %5, %4\n\t"
                                         "movb (%3, %%eax), %%al\n\t"
                                         "movb %%al, 3 (%1, %2)\n\t"
                                         "movl %4, %%eax\n\t"
                                         "shrl $16, %%eax\n\t"
                                         "addl %5, %4\n\t"
                                         "movb (%3, %%eax), %%al\n\t"
                                         "movb %%al, 4 (%1, %2)\n\t"
                                         "movl %4, %%eax\n\t"
                                         "shrl $16, %%eax\n\t"
                                         "addl %5, %4\n\t"
                                         "movb (%3, %%eax), %%al\n\t"
                                         "movb %%al, 5 (%1, %2)\n\t"
                                         "movl %4, %%eax\n\t"
                                         "shrl $16, %%eax\n\t"
                                         "addl %5, %4\n\t"
                                         "movb (%3, %%eax), %%al\n\t"
                                         "movb %%al, 6 (%1, %2)\n\t"
                                         "movl %4, %%eax\n\t"
                                         "shrl $16, %%eax\n\t"
                                         "addl %5, %4\n\t"
                                         "movb (%3, %%eax), %%al\n\t"
                                         "movb %%al, 7 (%1, %2)\n\t"
                                         :        /* output */
                                         :        /* input */
                                     "ax"(0), "r"(dp2), "r"(x), "r"(dp1),
                                         "r"(sx), "r"(xfactor)
                                         :"ax", "4"
                    );
#else
                    *(dp2 + x) = *(dp1 + (sx >> 16));
                    sx += xfactor;
                    *(dp2 + x + 1) = *(dp1 + (sx >> 16));
                    sx += xfactor;
                    *(dp2 + x + 2) = *(dp1 + (sx >> 16));
                    sx += xfactor;
                    *(dp2 + x + 3) = *(dp1 + (sx >> 16));
                    sx += xfactor;
                    *(dp2 + x + 4) = *(dp1 + (sx >> 16));
                    sx += xfactor;
                    *(dp2 + x + 5) = *(dp1 + (sx >> 16));
                    sx += xfactor;
                    *(dp2 + x + 6) = *(dp1 + (sx >> 16));
                    sx += xfactor;
                    *(dp2 + x + 7) = *(dp1 + (sx >> 16));
                    sx += xfactor;
#endif
                    x += 8;
                }
                while (x < w2) {
                    *(dp2 + x) = *(dp1 + (sx >> 16));
                    sx += xfactor;
                    x++;
                }
                dp2 += w2;
                y++;
                while (y < h2) {
                    int l;
                    int syint = sy >> 16;
                    sy += yfactor;
                    if ((sy >> 16) != syint)
                        break;
                    /* Copy identical lines. */
                    l = dp2 - dp2old;
                    memcpy(dp2, dp2old, l);
                    dp2old = dp2;
                    dp2 += l;
                    y++;
                }
                dp1 = _dp1 + (sy >> 16) * w1;
            }
        }
    break;
    case 2:
        {
            int y, sy;
            sy = 0;
            for (y = 0; y < h2;) {
                int sx = 0;
                uchar *dp2old = dp2;
                int x;
                x = 0;
                /* This can be greatly optimized with loop */
                /* unrolling; omitted to save space. */
                while (x < w2) {
                    *(unsigned short *) (dp2 + x * 2) =
                        *(unsigned short *) (dp1 + (sx >> 16) * 2);
                    sx += xfactor;
                    x++;
                }
                dp2 += w2 * 2;
                y++;
                while (y < h2) {
                    int l;
                    int syint = sy >> 16;
                    sy += yfactor;
                    if ((sy >> 16) != syint)
                        break;
                    /* Copy identical lines. */
                    l = dp2 - dp2old;
                    memcpy(dp2, dp2old, l);
                    dp2old = dp2;
                    dp2 += l;
                    y++;
                }
                dp1 = _dp1 + (sy >> 16) * w1 * 2;
            }
        }
    break;
    case 3:
        {
            int y, sy;
            sy = 0;
            for (y = 0; y < h2;) {
                int sx = 0;
                uchar *dp2old = dp2;
                int x;
                x = 0;
                /* This can be greatly optimized with loop */
                /* unrolling; omitted to save space. */
                while (x < w2) {
                    *(unsigned short *) (dp2 + x * 3) =
                        *(unsigned short *) (dp1 + (sx >> 16) * 3);
                    *(unsigned char *) (dp2 + x * 3 + 2) =
                        *(unsigned char *) (dp1 + (sx >> 16) * 3 + 2);
                    sx += xfactor;
                    x++;
                }
                dp2 += w2 * 3;
                y++;
                while (y < h2) {
                    int l;
                    int syint = sy >> 16;
                    sy += yfactor;
                    if ((sy >> 16) != syint)
                        break;
                    /* Copy identical lines. */
                    l = dp2 - dp2old;
                    memcpy(dp2, dp2old, l);
                    dp2old = dp2;
                    dp2 += l;
                    y++;
                }
                dp1 = _dp1 + (sy >> 16) * w1 * 3;
            }
        }
    break;
    case 4:
        {
            int y, sy;
            sy = 0;
            for (y = 0; y < h2;) {
                int sx = 0;
                uchar *dp2old = dp2;
                int x;
                x = 0;
                /* This can be greatly optimized with loop */
                /* unrolling; omitted to save space. */
                while (x < w2) {
                    *(unsigned *) (dp2 + x * 4) =
                        *(unsigned *) (dp1 + (sx >> 16) * 4);
                    sx += xfactor;
                    x++;
                }
                dp2 += w2 * 4;
                y++;
                while (y < h2) {
                    int l;
                    int syint = sy >> 16;
                    sy += yfactor;
                    if ((sy >> 16) != syint)
                        break;
                    /* Copy identical lines. */
                    l = dp2 - dp2old;
                    memcpy(dp2, dp2old, l);
                    dp2old = dp2;
                    dp2 += l;
                    y++;
                }
                dp1 = _dp1 + (sy >> 16) * w1 * 4;
            }
        }
    break;
    }

    return 0;
}