/**
 ** makepat.c
 **
 ** Copyright (c) 1995 Csaba Biegl, 820 Stirrup Dr, Nashville, TN 37221
 ** [e-mail: csaba@vuse.vanderbilt.edu]
 **
 ** Copyright (C) 1992, Csaba Biegl
 **   820 Stirrup Dr, Nashville, TN, 37221
 **   csaba@vuse.vanderbilt.edu
 **
 ** This file is part of the GRX graphics library.
 **
 ** The GRX graphics library is free software; you can redistribute it
 ** and/or modify it under some conditions; see the "copying.grx" file
 ** for details.
 **
 ** This library 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.
 **
 **/

#include "libgrx.h"
#include "allocate.h"

#define  BEST_MAX_LINE         128
#define  BEST_MAX_CONTEXT      2048L

#define GCM_MYMEMORY        1           /* set if my context memory */
#define GCM_MYCONTEXT       2           /* set if my context structure */

/*
 * try to replicate a pixmap for faster bitblt-s
 * in bitplane modes it is especially desirable to replicate until
 * the width is a multiple of 8
 */
static int _GrBestPixmapWidth(int wdt,int hgt)
{
	long total   = GrContextSize(wdt,hgt);
	int  linelen = GrLineOffset(wdt);
	int  factor  = 1;
	int  test;

	if(total == 0L) return(0);
#ifdef _MAXMEMPLANESIZE
	if(total > _MAXMEMPLANESIZE) return(0);
#endif
	if((test = (int)(BEST_MAX_CONTEXT / total)) > factor)
	    factor = test;
	if((test = (BEST_MAX_LINE / linelen)) < factor)
	    factor = test;
	while((factor >>= 1) != 0)
	    wdt <<= 1;
	return(wdt);
}

GrPattern *GrBuildPixmap(char *pixels,int w,int h,GrColorTableP ct)
{
	GrContext csave,cwork;
	GrPixmap  *result;
	unsigned  char *src;
	int  wdt,wdt2,fullw;
	int  hgt;
	GrColor color;

	if((fullw = _GrBestPixmapWidth(w,h)) <= 0) return(NULL);
	result = (GrPixmap *)malloc(sizeof(GrPixmap));
	if (result == NULL) return(NULL);

	if (!GrCreateContext(fullw,h,NULL,&cwork)) {
	  free(result);
	  return NULL;
	}
	csave = *CURC;
	*CURC = cwork;
	for(hgt = 0; hgt < h; hgt++) {
	    for(wdt2 = fullw; (wdt2 -= w) >= 0; ) {
		src = (unsigned char *)pixels;
		for(wdt = 0; wdt < w; wdt++) {
		    color = *src++;
		    if(ct != NULL) color = GR_CTABLE_COLOR(ct,color);
		    (*CURC->gc_driver->drawpixel)(wdt2+wdt,hgt,(color & C_COLOR));
		}
	    }
	    pixels += w;
	}
	*CURC = csave;
	result->pxp_source = cwork.gc_frame;
	result->pxp_source.gf_memflags = (GCM_MYCONTEXT | GCM_MYMEMORY);
	result->pxp_ispixmap = TRUE;
	result->pxp_width  = fullw;
	result->pxp_height = h;
	result->pxp_oper   = 0;
	return((GrPattern *)result);
}

GrPattern *GrBuildPixmapFromBits(char *bits,int w,int h,GrColor fgc,GrColor bgc)
{
	GrContext csave,cwork;
	GrPixmap  *result;
	unsigned  char *src;
	int  wdt,wdt2,fullw;
	int  hgt,mask,byte;

	if((fullw = _GrBestPixmapWidth(w,h)) <= 0) return(NULL);
	result = (GrPixmap *)malloc(sizeof(GrPixmap));
	if(result == NULL) return(NULL);

	if (!GrCreateContext(fullw,h,NULL,&cwork)) {
	  free(result);
	  return NULL;
	}
	csave = *CURC;
	*CURC = cwork;
	fgc &= C_COLOR;
	bgc &= C_COLOR;
	for(hgt = 0; hgt < h; hgt++) {
	    for(wdt2 = fullw; (wdt2 -= w) >= 0; ) {
		src  = (unsigned char *)bits;
		mask = byte = 0;
		for(wdt = w; --wdt >= 0; ) {
		    if((mask >>= 1) == 0) { mask = 0x80; byte = *src++; }
		    (*CURC->gc_driver->drawpixel)(wdt2+wdt,hgt,((byte & mask) ? fgc : bgc));
		}
	    }
	    bits += (w + 7) >> 3;
	}
	*CURC = csave;
	result->pxp_source = cwork.gc_frame;
	result->pxp_source.gf_memflags = (GCM_MYCONTEXT | GCM_MYMEMORY);
	result->pxp_ispixmap = TRUE;
	result->pxp_width  = fullw;
	result->pxp_height = h;
	result->pxp_oper   = 0;
	return((GrPattern *)result);
}

GrPattern *GrConvertToPixmap(GrContext *src)
{
	GrPixmap *result;

	if(src->gc_onscreen) return(NULL);
	result = malloc(sizeof(GrPixmap));
	if(result == NULL) return(NULL);
	result->pxp_source = src->gc_frame;
	result->pxp_source.gf_memflags = GCM_MYCONTEXT;
	result->pxp_ispixmap = TRUE;
	result->pxp_width  = src->gc_xmax + 1;
	result->pxp_height = src->gc_ymax + 1;
	result->pxp_oper   = 0;
	return((GrPattern *)result);
}


void GrDestroyPattern(GrPattern *p)
{
  if (!p) return;
  if (p->gp_ispixmap) {
    if ( p->gp_pxp_source.gf_memflags & GCM_MYMEMORY) {
      int ii;
      for ( ii = p->gp_pxp_source.gf_driver->num_planes; ii > 0; ii-- )
	 farfree(p->gp_pxp_source.gf_baseaddr[ii - 1]);
    }
    if ( p->gp_pxp_source.gf_memflags & GCM_MYCONTEXT )
      free(p);
    return;
  }
  if ( p->gp_bitmap.bmp_memflags ) free(p);
}

