libs-back/Source/art/image.m

/*
copyright 2002 Alexander Malmberg <alexander@malmberg.org>

   This file is part of GNUstep.

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.
   
   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.  See the GNU
   Library General Public License for more details.
   
   You should have received a copy of the GNU Library General Public
   License along with this library; if not, write to the Free
   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/*
Image drawing. DPSimage and helpers.
*/

#include <math.h>

#include <AppKit/NSAffineTransform.h>
#include <AppKit/NSGraphics.h>

#include "ARTGState.h"

#include "ARTWindowBuffer.h"
#include "blit.h"


static unsigned int _get_8_bits(const unsigned char *ptr,int bit_ofs,int num_bits)
{
/*
TODO: if we get values with more than 8 bits, we should round properly and
not just discard the extra bits
*/
  int i;
  unsigned int v;
  ptr+=bit_ofs/8;
  bit_ofs%=8;

  v=0;
  for (i=0;i<8 && i<num_bits;i++)
    {
      v<<=1;
      if ((*ptr)&(128>>bit_ofs))
	v|=1;
      bit_ofs++;
      if (bit_ofs==8)
	{
	  ptr++;
	  bit_ofs=0;
	}
    }
  switch (num_bits)
    {
    case 1:
      v*=255;
      break;
    case 2:
      v*=85;
      break;
    case 3:
      v=(v<<5)|(v<<2)|(v>>1);
      break;
    case 4:
      v=(v<<4)|v;
      break;
    case 5:
      v=(v<<3)|(v>>2);
      break;
    case 6:
      v=(v<<2)|(v>>4);
      break;
    case 7:
      v=(v<<1)|(v>>6);
      break;
    }
  return v;
}


typedef struct
{
  int width,height;
  int bits_per_sample,samples_per_pixel,bits_per_pixel,bytes_per_row;
  BOOL is_planar,has_alpha;
  const unsigned char **data;

  /*
    0  unknown, use colorspacename
    1  rgb
    2  cmyk
    3  gray
  */
  int colorspace;
  NSString *colorspacename;
} image_info_t;


static void _image_get_color_rgb_8(image_info_t *ii,render_run_t *ri,int x,int y)
{
  int ofs;

  if (x<0) x=0;
  if (y<0) y=0;
  if (x>=ii->width) x=ii->width-1;
  if (x>=ii->height) y=ii->height-1;

  ofs=ii->bytes_per_row*y+x*ii->bits_per_pixel/8;
  if (ii->is_planar)
    {
      ri->r=ii->data[0][ofs];
      ri->g=ii->data[1][ofs];
      ri->b=ii->data[2][ofs];
      if (ii->has_alpha)
	ri->a=ii->data[3][ofs];
      else
	ri->a=255;
    }
  else
    {
      ri->r=ii->data[0][ofs];
      ri->g=ii->data[0][ofs+1];
      ri->b=ii->data[0][ofs+2];
      if (ii->has_alpha)
	ri->a=ii->data[0][ofs+3];
      else
	ri->a=255;
    }
}

static void _image_get_color_rgb_cmyk_gray(image_info_t *ii,render_run_t *ri,int x,int y)
{
  int ofs,bit_ofs;
  int values[5];
  int i,j;

  if (x<0) x=0;
  if (y<0) y=0;
  if (x>=ii->width) x=ii->width-1;
  if (x>=ii->height) y=ii->height-1;

  ofs=y*ii->bytes_per_row;
  bit_ofs=x*ii->bits_per_pixel;

  for (i=j=0;i<ii->samples_per_pixel;i++)
    {
      values[i]=_get_8_bits(ii->data[j]+ofs,bit_ofs,ii->bits_per_sample);
      if (ii->is_planar)
	j++;
      else
	bit_ofs+=ii->bits_per_sample;
    }
  if (ii->has_alpha)
    ri->a=values[i-1];
  else
    ri->a=255;

  if (ii->colorspace==1)
    {
      ri->r=values[0];
      ri->g=values[1];
      ri->b=values[2];
    }
  else if (ii->colorspace==2)
    {
      j=255-values[0]-values[3];
      ri->r=j<0?0:j;
      j=255-values[1]-values[3];
      ri->g=j<0?0:j;
      j=255-values[2]-values[3];
      ri->b=j<0?0:j;
    }
  else if (ii->colorspace==3)
    {
      ri->r=ri->g=ri->b=values[0];
    }
}


@implementation ARTGState (image)

-(void) _image_do_rgb_transform: (image_info_t *)ii : (NSAffineTransform *)matrix
	: (void (*)(image_info_t *ii,render_run_t *ri,int x,int y))ifunc
{
/*
TODO:
seems to have problems with rotations. 0, 90, 180, 270 work fine, but others
seem to cause edges to be off by a pixel
*/
  int x[4],y[4];
  int tx[4],ty[4];
  float fx[4],fy[4];

  int cy,ey;
  int left_delta,next;
  int lx,lx_frac,ldx,ldx_frac,l_de,le;
  int rx,rx_frac,rdx,rdx_frac,r_de,re;
  int ltx,lty,ltx_frac,lty_frac,ldtx,ldty,ldtx_frac,ldty_frac;
  int rtx,rty,rtx_frac,rty_frac,rdtx,rdty,rdtx_frac,rdty_frac;

  NSPoint p;


  p=[matrix transformPoint: NSMakePoint(0,0)];
  fx[0]=p.x; fy[0]=p.y;
  p=[matrix transformPoint: NSMakePoint(ii->width,0)];
  fx[1]=p.x; fy[1]=p.y;
  p=[matrix transformPoint: NSMakePoint(ii->width,ii->height)];
  fx[2]=p.x; fy[2]=p.y;
  p=[matrix transformPoint: NSMakePoint(0,ii->height)];
  fx[3]=p.x; fy[3]=p.y;

  if (fabs(fx[0]-floor(fx[0]+.5))<0.001) fx[0]=floor(fx[0]+.5);
  if (fabs(fx[1]-floor(fx[1]+.5))<0.001) fx[1]=floor(fx[1]+.5);
  if (fabs(fx[2]-floor(fx[2]+.5))<0.001) fx[2]=floor(fx[2]+.5);
  if (fabs(fx[3]-floor(fx[3]+.5))<0.001) fx[3]=floor(fx[3]+.5);
  if (fabs(fy[0]-floor(fy[0]+.5))<0.001) fy[0]=floor(fy[0]+.5);
  if (fabs(fy[1]-floor(fy[1]+.5))<0.001) fy[1]=floor(fy[1]+.5);
  if (fabs(fy[2]-floor(fy[2]+.5))<0.001) fy[2]=floor(fy[2]+.5);
  if (fabs(fy[3]-floor(fy[3]+.5))<0.001) fy[3]=floor(fy[3]+.5);

  x[0]=floor(fx[0]); y[0]=wi->sy-floor(fy[0]);
  x[1]=floor(fx[1]); y[1]=wi->sy-floor(fy[1]);
  x[2]=floor(fx[2]); y[2]=wi->sy-floor(fy[2]);
  x[3]=floor(fx[3]); y[3]=wi->sy-floor(fy[3]);

  tx[0]=0;         ty[0]=ii->height;
  tx[1]=ii->width; ty[1]=ii->height;
  tx[2]=ii->width; ty[2]=0;
  tx[3]=0;         ty[3]=0;

  cy=y[le=0];
  if (y[1]<cy) cy=y[le=1];
  if (y[2]<cy) cy=y[le=2];
  if (y[3]<cy) cy=y[le=3];
  re=le;

  ey=y[0];
  if (y[1]>ey) ey=y[1];
  if (y[2]>ey) ey=y[2];
  if (y[3]>ey) ey=y[3];

  if (x[(le+1)&3]<x[(le-1)&3])
    left_delta=1;
  else
    left_delta=-1;

  /* silence the compiler */
  lx=lx_frac=ldx=ldx_frac=l_de=0;
  rx=rx_frac=rdx=rdx_frac=r_de=0;
  ltx=lty=ltx_frac=lty_frac=ldtx=ldty=ldtx_frac=ldty_frac=0;
  rtx=rty=rtx_frac=rty_frac=rdtx=rdty=rdtx_frac=rdty_frac=0;

  while (cy<=ey && cy<clip_y1)
    {
      if (cy==y[le])
	{
	  next=(le+left_delta)&3;
	  while (y[le]==y[next])
	    {
	      le=next;
	      next=(le+left_delta)&3;
	    }
	  l_de=y[next]-y[le];
	  lx=x[le];
	  lx_frac=0;
	  ldx=(x[next]-x[le])/l_de;
	  ldx_frac=(x[next]-x[le])%l_de;

	  ltx=tx[le];
	  lty=ty[le];
	  ltx_frac=0;
	  lty_frac=0;
	  ldtx=(tx[next]-tx[le])/l_de;
	  ldty=(ty[next]-ty[le])/l_de;
	  ldtx_frac=(tx[next]-tx[le])%l_de;
	  ldty_frac=(ty[next]-ty[le])%l_de;

	  le=next;
	}
      else
	{
	  lx+=ldx;
	  lx_frac+=ldx_frac;
	  if (lx_frac<0)
	    lx--,lx_frac+=l_de;
	  if (lx_frac>l_de)
	    lx++,lx_frac-=l_de;

	  ltx+=ldtx;
	  ltx_frac+=ldtx_frac;
	  if (ltx_frac<0)
	    ltx--,ltx_frac+=l_de;
	  if (ltx_frac>l_de)
	    ltx++,ltx_frac-=l_de;

	  lty+=ldty;
	  lty_frac+=ldty_frac;
	  if (lty_frac<0)
	    lty--,lty_frac+=l_de;
	  if (lty_frac>l_de)
	    lty++,lty_frac-=l_de;
	}

      if (cy==y[re])
	{
	  next=(re-left_delta)&3;
	  while (y[re]==y[next])
	    {
	      re=next;
	      next=(re-left_delta)&3;
	    }
	  r_de=y[next]-y[re];
	  rx=x[re];
	  rx_frac=r_de-1; /* TODO? */
	  rdx=(x[next]-x[re])/r_de;
	  rdx_frac=(x[next]-x[re])%r_de;

	  rtx=tx[re];
	  rty=ty[re];
	  rtx_frac=0;
	  rty_frac=0;
	  rdtx=(tx[next]-tx[re])/r_de;
	  rdty=(ty[next]-ty[re])/r_de;
	  rdtx_frac=(tx[next]-tx[re])%r_de;
	  rdty_frac=(ty[next]-ty[re])%r_de;

	  re=next;
	}
      else
	{
	  rx+=rdx;
	  rx_frac+=rdx_frac;
	  if (rx_frac<0)
	    rx--,rx_frac+=r_de;
	  if (rx_frac>r_de)
	    rx++,rx_frac-=r_de;

	  rtx+=rdtx;
	  rtx_frac+=rdtx_frac;
	  if (rtx_frac<0)
	    rtx--,rtx_frac+=r_de;
	  if (rtx_frac>r_de)
	    rtx++,rtx_frac-=r_de;

	  rty+=rdty;
	  rty_frac+=rdty_frac;
	  if (rty_frac<0)
	    rty--,rty_frac+=r_de;
	  if (rty_frac>r_de)
	    rty++,rty_frac-=r_de;
	}

      if (cy>=clip_y0 && rx>lx)
	{
	  render_run_t ri;
	  int x0,x1,de;
	  int tx,ty,tx_frac,ty_frac,dtx,dty,dtx_frac,dty_frac;
	  int delta;

	  x0=lx;
	  x1=rx;
	  de=x1-x0;

	  tx=ltx;
	  ty=lty;
	  tx_frac=ltx_frac*de*r_de;
	  ty_frac=lty_frac*de*r_de;
	  de*=r_de*l_de;

	  delta=(rtx*r_de+rtx_frac)*l_de-(ltx*l_de+ltx_frac)*r_de;
	  dtx=delta/de;
	  dtx_frac=delta%de;

	  delta=(rty*r_de+rty_frac)*l_de-(lty*l_de+lty_frac)*r_de;
	  dty=delta/de;
	  dty_frac=delta%de;

	  /*
	    x0 x1/x2 -> y0 y1/y2  z
	    ((y0*y2+y1)*x2-(x0*x2+x1)*y2)/(x2*y2*z)
	  */

	  if (x0<clip_x0)
	    {
	      tx+=dtx*(clip_x0-x0);
	      ty+=dty*(clip_x0-x0);
	      tx_frac+=dtx_frac*(clip_x0-x0);
	      while (tx_frac<0)
		tx--,tx_frac+=de;
	      while (tx_frac>=de)
		tx++,tx_frac-=de;
	      ty_frac+=dty_frac*(clip_x0-x0);
	      while (ty_frac<0)
		ty--,ty_frac+=de;
	      while (ty_frac>=de)
		ty++,ty_frac-=de;
	      x0=clip_x0;
	    }
	  if (x1>=clip_x1) x1=clip_x1-1;

	  ri.dst=wi->data+x0*DI.bytes_per_pixel+cy*wi->bytes_per_line;
	  ri.dsta=wi->alpha+x0+cy*wi->sx;

	  if (wi->has_alpha)
	    {
	      for (;x0<x1;x0++,ri.dst+=DI.bytes_per_pixel,ri.dsta++)
		{
		  ifunc(ii,&ri,tx,ty);
		  RENDER_RUN_ALPHA_A(&ri,1);

		  tx+=dtx;
		  ty+=dty;
		  tx_frac+=dtx_frac;
		  if (tx_frac<0)
		    tx--,tx_frac+=de;
		  if (tx_frac>=de)
		    tx++,tx_frac-=de;
		  ty_frac+=dty_frac;
		  if (ty_frac<0)
		    ty--,ty_frac+=de;
		  if (ty_frac>=de)
		    ty++,ty_frac-=de;
		}
	    }
	  else
	    {
	      for (;x0<x1;x0++,ri.dst+=DI.bytes_per_pixel)
		{
		  ifunc(ii,&ri,tx,ty);
		  RENDER_RUN_ALPHA(&ri,1);

		  tx+=dtx;
		  ty+=dty;
		  tx_frac+=dtx_frac;
		  if (tx_frac<0)
		    tx--,tx_frac+=de;
		  if (tx_frac>=de)
		    tx++,tx_frac-=de;
		  ty_frac+=dty_frac;
		  if (ty_frac<0)
		    ty--,ty_frac+=de;
		  if (ty_frac>=de)
		    ty++,ty_frac-=de;
		}
	    }
	}

      cy++;
    }
}


- (void)DPSimage: (NSAffineTransform*) matrix
		: (int) pixelsWide : (int) pixelsHigh
		: (int) bitsPerSample : (int) samplesPerPixel 
		: (int) bitsPerPixel : (int) bytesPerRow : (BOOL) isPlanar
		: (BOOL) hasAlpha : (NSString *) colorSpaceName
		: (const unsigned char *const [5]) data
{
  BOOL identity_transform,is_rgb;
  image_info_t ii;

  if (!wi || !wi->data) return;
  if (all_clipped) return;

  [matrix prependTransform: ctm];
  if (fabs(matrix->matrix.m11-1.0)<0.001 && fabs(matrix->matrix.m12)<0.001 &&
      fabs(matrix->matrix.m22-1.0)<0.001 && fabs(matrix->matrix.m21)<0.001)
    identity_transform=YES;
  else
    identity_transform=NO;

  if (colorSpaceName==NSDeviceRGBColorSpace ||
      colorSpaceName==NSCalibratedRGBColorSpace)
    is_rgb=YES;
  else
    is_rgb=NO;

  /* optimize common case */
  if (identity_transform && is_rgb &&
      bitsPerSample==8 && !isPlanar && bytesPerRow==samplesPerPixel*pixelsWide &&
      ((samplesPerPixel==3 && bitsPerPixel==24 && !hasAlpha) ||
       (samplesPerPixel==4 && bitsPerPixel==32 && hasAlpha)))
    {
      int x,y,ox,oy;
      const unsigned char *src=data[0];
      unsigned char *alpha_dest;
      render_run_t ri;

      if (wi->has_alpha)
	{
	  if (DI.inline_alpha)
	    alpha_dest=wi->data+DI.inline_alpha_ofs;
	  else
	    alpha_dest=wi->alpha;
	}
      else
	alpha_dest=NULL;
	
      ox=[matrix transformPoint: NSMakePoint(0,0)].x;
      oy=wi->sy-[matrix transformPoint: NSMakePoint(0,0)].y-pixelsHigh;
	
      for (y=0;y<pixelsHigh;y++)
	{
	  for (x=0;x<pixelsWide;x++)
	    {
	      if (x+ox<clip_x0 || x+ox>=clip_x1 || y+oy<clip_y0 || y+oy>=clip_y1)
		{
		  if (hasAlpha)
		    src+=4;
		  else
		    src+=3;
		  continue;
		}
	      ri.dst=wi->data+(x+ox)*DI.bytes_per_pixel+(y+oy)*wi->bytes_per_line;
	      ri.dsta=wi->alpha+(x+ox)+(y+oy)*wi->sx;
	      ri.r=src[0];
	      ri.g=src[1];
	      ri.b=src[2];
	      if (hasAlpha)
		{
		  ri.a=src[3];
		  /* TODO: find out if input is premultiplied or not */
		  if (ri.a && ri.a!=255)
		    {
		      ri.r=(255*ri.r)/ri.a;
		      ri.g=(255*ri.g)/ri.a;
		      ri.b=(255*ri.b)/ri.a;
		    }
		  if (alpha_dest)
		    {
		      if (src[3]==255)
			RENDER_RUN_OPAQUE_A(&ri,1);
		      else if (src[3])
			RENDER_RUN_ALPHA_A(&ri,1);
		    }
		  else
		    {
		      if (src[3]==255)
			RENDER_RUN_OPAQUE(&ri,1);
		      else if (src[3])
			RENDER_RUN_ALPHA(&ri,1);
		    }
		  src+=4;
		}
	      else
		{
		  ri.a=255;
		  if (alpha_dest)
		    RENDER_RUN_OPAQUE_A(&ri,1);
		  else
		    RENDER_RUN_OPAQUE(&ri,1);
		  src+=3;
		}
	    }
	}
      return;
    }

  ii.bits_per_sample=bitsPerSample;
  ii.bits_per_pixel=bitsPerPixel;
  ii.is_planar=isPlanar;
  ii.has_alpha=hasAlpha;
  ii.width=pixelsWide;
  ii.height=pixelsHigh;
  ii.samples_per_pixel=samplesPerPixel;
  ii.bytes_per_row=bytesPerRow;
  ii.data=(const unsigned char **)data;

  if (bitsPerSample==8 && is_rgb &&
      ((samplesPerPixel==3 && !hasAlpha) ||
       (samplesPerPixel==4 && hasAlpha)))
    {
      [self _image_do_rgb_transform: &ii : matrix : _image_get_color_rgb_8];
      return;
    }

  if (is_rgb)
    ii.colorspace=1;
  else if (colorSpaceName==NSDeviceCMYKColorSpace)
    ii.colorspace=2;
  else if (colorSpaceName==NSDeviceWhiteColorSpace ||
	   colorSpaceName==NSDeviceBlackColorSpace ||
	   colorSpaceName==NSCalibratedWhiteColorSpace ||
	   colorSpaceName==NSCalibratedBlackColorSpace)
    ii.colorspace=3;
  else
    ii.colorspace=0;

  if (ii.colorspace!=0)
    {
      [self _image_do_rgb_transform: &ii : matrix : _image_get_color_rgb_cmyk_gray];
      return;
    }

  NSLog(@"unimplemented DPSimage  %ix%i  |%@|  bips=%i spp=%i bipp=%i bypr=%i  planar=%i alpha=%i\n",
	pixelsWide,pixelsHigh,matrix,
	bitsPerSample,samplesPerPixel,bitsPerPixel,bytesPerRow,isPlanar,
	hasAlpha);
}

@end