/* $Id: drawpix.c,v 3.14 1998/08/01 04:52:47 brianp Exp $ */

/*
 * Mesa 3-D graphics library
 * Version:  3.0
 * Copyright (C) 1995-1998  Brian Paul
 *
 * 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.
 */


/*
 * $Log: drawpix.c,v $
 * Revision 3.14  1998/08/01 04:52:47  brianp
 * fixed conformance problems in GL_DEPTH_COMPONENT and GL_STENCIL_INDEX code
 *
 * Revision 3.13  1998/07/17 03:24:16  brianp
 * added Pixel.ScaleOrBiasRGBA field
 *
 * Revision 3.12  1998/06/28 22:32:22  brianp
 * fixed Mac compilation problem (Randy Frank and Miklos Fazekas)
 *
 * Revision 3.11  1998/06/01 00:38:13  brianp
 * fixed off-by-one bug in glDrawPixels clipping (Randy Frank)
 *
 * Revision 3.10  1998/05/31 23:50:36  brianp
 * cleaned up a few Solaris compiler warnings
 *
 * Revision 3.9  1998/04/01 02:58:52  brianp
 * applied Miklos Fazekas's 3-31-98 Macintosh changes
 *
 * Revision 3.8  1998/03/27 03:39:14  brianp
 * fixed G++ warnings
 *
 * Revision 3.7  1998/03/26 03:09:09  brianp
 * added GL_LUMINANCE and GL_LUMINANCE_ALPHA to gl_direct_DrawPixels()
 *
 * Revision 3.6  1998/03/25 01:56:03  brianp
 * fixed bug when Zoom.Y != 1.0 and top/bottom clipping needed (Randy Frank)
 *
 * Revision 3.5  1998/03/22 16:42:30  brianp
 * added CI->RGBA conversion to gl_direct_DrawPixels()
 *
 * Revision 3.4  1998/03/10 01:28:22  brianp
 * moved a few DEFARRY macros
 *
 * Revision 3.3  1998/02/08 20:22:14  brianp
 * LOTS of clean-up and rewriting
 *
 * Revision 3.2  1998/02/04 00:33:45  brianp
 * fixed a few cast problems for Amiga StormC compiler
 *
 * Revision 3.1  1998/02/01 22:16:34  brianp
 * include different headers (zooming)
 *
 * Revision 3.0  1998/01/31 20:51:03  brianp
 * initial rev
 *
 */


#ifdef PC_HEADER
#include "all.h"
#else
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include "context.h"
#include "drawpix.h"
#include "feedback.h"
#include "image.h"
#include "macros.h"
#include "pixel.h"
#include "span.h"
#include "stencil.h"
#include "types.h"
#include "zoom.h"
#endif



/* TODO:  apply texture mapping to fragments */


/*
 * Try to do a fast glDrawPixels.  Conditions include:
 *   not using a display list
 *   simple pixel unpacking
 *   no raster ops
 *   etc....
 * Return:  GL_TRUE if success, GL_FALSE if slow path must be used instead
 */
GLboolean gl_direct_DrawPixels( GLcontext *ctx,
				const struct gl_pixelstore_attrib *unpack,
				GLsizei width, GLsizei height,
				GLenum format, GLenum type,
				const GLvoid *pixels )
{
   GLubyte rgb[MAX_WIDTH][3];
   GLubyte rgba[MAX_WIDTH][4];

   if (INSIDE_BEGIN_END(ctx)) {
      gl_error( ctx, GL_INVALID_OPERATION, "glDrawPixels" );
      return GL_TRUE;
   }

   if (!ctx->Current.RasterPosValid) {
      /* no-op */
      return GL_TRUE;
   }

   if (ctx->NewState) {
      gl_update_state(ctx);
   }

   /* see if device driver can do the drawpix */
   if (ctx->Driver.DrawPixels) {
      GLint x = (GLint) (ctx->Current.RasterPos[0] + 0.5F);
      GLint y = (GLint) (ctx->Current.RasterPos[1] + 0.5F);
      if ((*ctx->Driver.DrawPixels)(ctx, x, y, width, height, format, type,
				    unpack, pixels))
	 return GL_TRUE;
   }

   if ((ctx->RasterMask&(~(SCISSOR_BIT|WINCLIP_BIT)))==0
       && ctx->Pixel.RedBias==0.0 && ctx->Pixel.RedScale==1.0
       && ctx->Pixel.GreenBias==0.0 && ctx->Pixel.GreenScale==1.0
       && ctx->Pixel.BlueBias==0.0 && ctx->Pixel.BlueScale==1.0
       && ctx->Pixel.AlphaBias==0.0 && ctx->Pixel.AlphaScale==1.0
       && ctx->Pixel.IndexShift==0 && ctx->Pixel.IndexOffset==0
       && ctx->Pixel.MapColorFlag==0
       && unpack->Alignment==1
       && !unpack->SwapBytes
       && !unpack->LsbFirst) {

      GLint destX = (GLint) (ctx->Current.RasterPos[0] + 0.5F);
      GLint destY = (GLint) (ctx->Current.RasterPos[1] + 0.5F);
      GLint drawWidth = width;           /* actual width drawn */
      GLint drawHeight = height;         /* actual height drawn */
      GLint skipPixels = unpack->SkipPixels;
      GLint skipRows = unpack->SkipRows;
      GLint rowLength;
      GLdepth zSpan[MAX_WIDTH];  /* only used when zooming */
      GLint zoomY0;

      if (unpack->RowLength > 0)
	 rowLength = unpack->RowLength;
      else
	 rowLength = width;

      /* If we're not using pixel zoom then do all clipping calculations
       * now.  Otherwise, we'll let the gl_write_zoomed_*_span() functions
       * handle the clipping.
       */
      if (ctx->Pixel.ZoomX==1.0F && ctx->Pixel.ZoomY==1.0F) {
	 /* horizontal clipping */
	 if (destX < ctx->Buffer->Xmin) {
	    skipPixels += (ctx->Buffer->Xmin - destX);
	    drawWidth  -= (ctx->Buffer->Xmin - destX);
	    destX = ctx->Buffer->Xmin;
	 }
	 if (destX + drawWidth > ctx->Buffer->Xmax)
	    drawWidth -= (destX + drawWidth - ctx->Buffer->Xmax - 1);
	 if (drawWidth <= 0)
	    return GL_TRUE;

	 /* vertical clipping */
	 if (destY < ctx->Buffer->Ymin) {
	    skipRows   += (ctx->Buffer->Ymin - destY);
	    drawHeight -= (ctx->Buffer->Ymin - destY);
	    destY = ctx->Buffer->Ymin;
	 }
	 if (destY + drawHeight > ctx->Buffer->Ymax)
	    drawHeight -= (destY + drawHeight - ctx->Buffer->Ymax - 1);
	 if (drawHeight <= 0)
	    return GL_TRUE;
      }
      else {
	 /* setup array of fragment Z value to pass to zoom function */
	 GLdepth z = (GLdepth) (ctx->Current.RasterPos[2] * DEPTH_SCALE);
	 GLint i;
	 assert(drawWidth < MAX_WIDTH);
	 for (i=0; i<drawWidth; i++)
	    zSpan[i] = z;

	 /* save Y value of first row */
	 zoomY0 = (GLint) (ctx->Current.RasterPos[1] + 0.5F);
      }


      /*
       * Ready to draw!
       * The window region at (destX, destY) of size (drawWidth, drawHeight)
       * will be written to.
       * We'll take pixel data from buffer pointed to by "pixels" but we'll
       * skip "skipRows" rows and skip "skipPixels" pixels/row.
       */

      if (format==GL_RGBA && type==GL_UNSIGNED_BYTE) {
	 if (ctx->Visual->RGBAflag) {
	    GLubyte *src = (GLubyte *) pixels
	       + (skipRows * rowLength + skipPixels) * 4;
	    if (ctx->Pixel.ZoomX==1.0F && ctx->Pixel.ZoomY==1.0F) {
	       /* no zooming */
	       GLint row;
	       for (row=0; row<drawHeight; row++) {
		  (*ctx->Driver.WriteRGBASpan)(ctx, drawWidth, destX, destY,
					       (void *) src, NULL);
		  src += rowLength * 4;
		  destY++;
	       }
	    }
	    else {
	       /* with zooming */
	       GLint row;
	       for (row=0; row<drawHeight; row++) {
		  gl_write_zoomed_rgba_span(ctx, drawWidth, destX, destY,
					    zSpan, (void *) src, zoomY0);
		  src += rowLength * 4;
		  destY++;
	       }
	    }
	 }
	 return GL_TRUE;
      }
      else if (format==GL_RGB && type==GL_UNSIGNED_BYTE) {
	 if (ctx->Visual->RGBAflag) {
	    GLubyte *src = (GLubyte *) pixels
	       + (skipRows * rowLength + skipPixels) * 3;
	    if (ctx->Pixel.ZoomX==1.0F && ctx->Pixel.ZoomY==1.0F) {
	       GLint row;
	       for (row=0; row<drawHeight; row++) {
		  (*ctx->Driver.WriteRGBSpan)(ctx, drawWidth, destX, destY,
					      (void *) src, NULL);
		  src += rowLength * 3;
		  destY++;
	       }
	    }
	    else {
	       /* with zooming */
	       GLint row;
	       for (row=0; row<drawHeight; row++) {
		  gl_write_zoomed_rgb_span(ctx, drawWidth, destX, destY,
					   zSpan, (void *) src, zoomY0);
		  src += rowLength * 3;
		  destY++;
	       }
	    }
	 }
	 return GL_TRUE;
      }
      else if (format==GL_LUMINANCE && type==GL_UNSIGNED_BYTE) {
	 if (ctx->Visual->RGBAflag) {
	    GLubyte *src = (GLubyte *) pixels
	       + (skipRows * rowLength + skipPixels);
	    if (ctx->Pixel.ZoomX==1.0F && ctx->Pixel.ZoomY==1.0F) {
	       /* no zooming */
	       GLint row;
	       assert(drawWidth < MAX_WIDTH);
	       for (row=0; row<drawHeight; row++) {
		  GLint i;
		  for (i=0;i<drawWidth;i++) {
		     rgb[i][0] = src[i];
		     rgb[i][1] = src[i];
		     rgb[i][2] = src[i];
		  }
		  (*ctx->Driver.WriteRGBSpan)(ctx, drawWidth, destX, destY,
					      (void *) rgb, NULL);
		  src += rowLength;
		  destY++;
	       }
	    }
	    else {
	       /* with zooming */
	       GLint row;
	       assert(drawWidth < MAX_WIDTH);
	       for (row=0; row<drawHeight; row++) {
		  GLint i;
		  for (i=0;i<drawWidth;i++) {
		     rgb[i][0] = src[i];
		     rgb[i][1] = src[i];
		     rgb[i][2] = src[i];
		  }
		  gl_write_zoomed_rgb_span(ctx, drawWidth, destX, destY,
					   zSpan, (void *) rgb, zoomY0);
		  src += rowLength;
		  destY++;
	       }
	    }
	 }
	 return GL_TRUE;
      }
      else if (format==GL_LUMINANCE_ALPHA && type==GL_UNSIGNED_BYTE) {
	 if (ctx->Visual->RGBAflag) {
	    GLubyte *src = (GLubyte *) pixels
	       + (skipRows * rowLength + skipPixels)*2;
	    if (ctx->Pixel.ZoomX==1.0F && ctx->Pixel.ZoomY==1.0F) {
	       /* no zooming */
	       GLint row;
	       assert(drawWidth < MAX_WIDTH);
	       for (row=0; row<drawHeight; row++) {
		  GLint i;
		  GLubyte *ptr = src;
		  for (i=0;i<drawWidth;i++) {
		     rgba[i][0] = *ptr;
		     rgba[i][1] = *ptr;
		     rgba[i][2] = *ptr++;
		     rgba[i][3] = *ptr++;
		  }
		  (*ctx->Driver.WriteRGBASpan)(ctx, drawWidth, destX, destY,
					       (void *) rgba, NULL);
		  src += rowLength*2;
		  destY++;
	       }
	    }
	    else {
	       /* with zooming */
	       GLint row;
	       assert(drawWidth < MAX_WIDTH);
	       for (row=0; row<drawHeight; row++) {
		  GLubyte *ptr = src;
		  GLint i;
		  for (i=0;i<drawWidth;i++) {
		     rgba[i][0] = *ptr;
		     rgba[i][1] = *ptr;
		     rgba[i][2] = *ptr++;
		     rgba[i][3] = *ptr++;
		  }
		  gl_write_zoomed_rgba_span(ctx, drawWidth, destX, destY,
					    zSpan, (void *) rgba, zoomY0);
		  src += rowLength*2;
		  destY++;
	       }
	    }
	 }
	 return GL_TRUE;
      }
      else if (format==GL_COLOR_INDEX && type==GL_UNSIGNED_BYTE) {
	 GLubyte *src = (GLubyte *) pixels + skipRows * rowLength + skipPixels;
	 if (ctx->Visual->RGBAflag) {
	    /* convert CI data to RGBA */
	    if (ctx->Pixel.ZoomX==1.0F && ctx->Pixel.ZoomY==1.0F) {
	       /* no zooming */
	       GLint row;
	       for (row=0; row<drawHeight; row++) {
		  assert(drawWidth < MAX_WIDTH);
		  gl_map_ci8_to_rgba(ctx, drawWidth, src, rgba);
#ifndef __STORM__
		  (*ctx->Driver.WriteRGBASpan)(ctx, drawWidth, destX, destY,
					       rgba, NULL);
#else
		  (*ctx->Driver.WriteRGBASpan)(ctx, drawWidth, destX, destY,
					       (CONST GLubyte(*)[4])rgba, NULL);
#endif
		  src += rowLength;
		  destY++;
	       }
	       return GL_TRUE;
	    }
	    else {
	       /* with zooming */
	       GLint row;
	       for (row=0; row<drawHeight; row++) {
		  assert(drawWidth < MAX_WIDTH);
		  gl_map_ci8_to_rgba(ctx, drawWidth, src, rgba);
		  gl_write_zoomed_rgba_span(ctx, drawWidth, destX, destY,
					    zSpan, (void *) rgba, zoomY0);
		  src += rowLength;
		  destY++;
	       }
	       return GL_TRUE;
	    }
	 }
	 else {
	    /* write CI data to CI frame buffer */
	    GLint row;
	    if (ctx->Pixel.ZoomX==1.0F && ctx->Pixel.ZoomY==1.0F) {
	       /* no zooming */
	       for (row=0; row<drawHeight; row++) {
		  (*ctx->Driver.WriteCI8Span)(ctx, drawWidth, destX, destY,
					      src, NULL);
		  src += rowLength;
		  destY++;
	       }
	       return GL_TRUE;
	    }
	    else {
	       /* with zooming */
	       return GL_FALSE;
	    }
	 }
      }
      else {
	 /* can't handle this pixel format and/or data type here */
	 return GL_FALSE;
      }
   }
   else {
      /* can't do direct render, have to use slow path */
      return GL_FALSE;
   }
}



/*
 * Do glDrawPixels of index pixels.
 */
static void draw_index_pixels( GLcontext *ctx, GLint x, GLint y,
			       const struct gl_image *image )
{
   GLint width, height, widthInBytes;
   const GLint desty = y;
   GLint i, j;
   GLdepth zspan[MAX_WIDTH];
   const GLboolean zoom = ctx->Pixel.ZoomX!=1.0 || ctx->Pixel.ZoomY!=1.0;

   assert(image);
   assert(image->Format == GL_COLOR_INDEX);

   width = image->Width;
   height = image->Height;
   if (image->Type == GL_BITMAP)
      widthInBytes = (width + 7) / 8;
   else
      widthInBytes = width;

   /* Fragment depth values */
   if (ctx->Depth.Test) {
      GLdepth zval = (GLdepth) (ctx->Current.RasterPos[2] * DEPTH_SCALE);
      for (i=0;i<width;i++) {
	 zspan[i] = zval;
      }
   }

   /* process the image row by row */
   for (i=0;i<height;i++,y++) {
      GLuint ispan[MAX_WIDTH];

      /* convert to uints */
      switch (image->Type) {
	 case GL_UNSIGNED_BYTE:
	    {
	       GLubyte *src = (GLubyte *) image->Data + i * width;
	       for (j=0;j<width;j++) {
		  ispan[j] = (GLuint) *src++;
	       }
	    }
	    break;
	 case GL_FLOAT:
	    {
	       GLfloat *src = (GLfloat *) image->Data + i * width;
	       for (j=0;j<width;j++) {
		  ispan[j] = (GLuint) (GLint) *src++;
	       }
	    }
	    break;
	 case GL_BITMAP:
	    {
	       GLubyte *src = (GLubyte *) image->Data + i * widthInBytes;
	       for (j=0;j<width;j++) {
		  ispan[j] = ( src[j >> 3] >> (7 - (j & 0x7)) ) & 1;
	       }
	    }
	    break;
	 default:
	    gl_problem( ctx, "draw_index_pixels type" );
	    return;
      }

      /* apply shift and offset */
      if (ctx->Pixel.IndexOffset || ctx->Pixel.IndexShift) {
	 gl_shift_and_offset_ci( ctx, width, ispan );
      }

      if (ctx->Visual->RGBAflag) {
	 /* Convert index to RGBA and write to frame buffer */
	 GLubyte rgba[MAX_WIDTH][4];
	 gl_map_ci_to_rgba( ctx, width, ispan, rgba );
	 if (zoom) {
#ifndef __STORM__
	    gl_write_zoomed_rgba_span( ctx, width, x, y, zspan, rgba, desty );
#else
	    gl_write_zoomed_rgba_span( ctx, width, x, y, zspan, (CONST GLubyte(*)[4])rgba, desty );
#endif
	 }
	 else {
	    gl_write_rgba_span( ctx, width, x, y, zspan, rgba, GL_BITMAP );
	 }
      }
      else {
	 /* optionally apply index map then write to frame buffer */
	 if (ctx->Pixel.MapColorFlag) {
	    gl_map_ci(ctx, width, ispan);
	 }
	 if (zoom) {
	    gl_write_zoomed_index_span( ctx, width, x, y, zspan, ispan, desty );
	 }
	 else {
	    gl_write_index_span( ctx, width, x, y, zspan, ispan, GL_BITMAP );
	 }
      }
   }

}



/*
 * Do glDrawPixels of stencil image.  The image datatype may either
 * be GLubyte or GLbitmap.
 */
static void draw_stencil_pixels( GLcontext *ctx, GLint x, GLint y,
				 const struct gl_image *image )
{
   GLint widthInBytes, width, height;
   const GLint desty = y;
   GLint i;
   const GLboolean zoom = ctx->Pixel.ZoomX!=1.0 || ctx->Pixel.ZoomY!=1.0;

   assert(image);
   assert(image->Format == GL_STENCIL_INDEX);
   assert(image->Type == GL_UNSIGNED_BYTE || image->Type == GL_BITMAP);

   if (image->Type == GL_UNSIGNED_BYTE)
      widthInBytes = image->Width;
   else
      widthInBytes = (image->Width + 7) / 8;
   width = image->Width;
   height = image->Height;

   /* process the image row by row */
   for (i=0;i<height;i++,y++) {
      GLstencil *src = (GLstencil*)image->Data + i * widthInBytes;
      GLstencil *stencilValues;
      GLstencil stencilCopy[MAX_WIDTH];

      if (image->Type == GL_BITMAP) {
	 /* convert bitmap data to GLubyte (0 or 1) data */
	 GLint j;
	 for (j = 0; j < width; j++) {
	    stencilCopy[j] = ( src[j >> 3] >> (7 - (j & 0x7)) ) & 1;
	 }
	 src = stencilCopy;
      }

      if (ctx->Pixel.IndexOffset || ctx->Pixel.IndexShift
	  || ctx->Pixel.MapStencilFlag) {

	 /* make copy of stencil values */
	 if (src != stencilCopy)
	    MEMCPY( stencilCopy, src, width * sizeof(GLstencil));

	 /* apply shift and offset */
	 if (ctx->Pixel.IndexOffset || ctx->Pixel.IndexShift) {
	    gl_shift_and_offset_stencil( ctx, width, stencilCopy );
	 }

	 /* mapping */
	 if (ctx->Pixel.MapStencilFlag) {
	    gl_map_stencil( ctx, width, stencilCopy );
	 }

	 stencilValues = stencilCopy;
      }
      else {
	 /* use stencil values in-place */
	 stencilValues = src;
      }

      /* write stencil values to stencil buffer */
      if (zoom) {
	 gl_write_zoomed_stencil_span( ctx, (GLuint) width, x, y,
				       stencilValues, desty );
      }
      else {
	 gl_write_stencil_span( ctx, (GLuint) width, x, y, stencilValues );
      }
   }
}



/*
 * Do a glDrawPixels of depth values.
 */
static void draw_depth_pixels( GLcontext *ctx, GLint x, GLint y,
			       const struct gl_image *image )
{
   GLint width, height;
   const GLint desty = y;
   GLubyte rgba[MAX_WIDTH][4];
   GLuint ispan[MAX_WIDTH];
   const GLboolean bias_or_scale = ctx->Pixel.DepthBias!=0.0 || ctx->Pixel.DepthScale!=1.0;
   const GLboolean zoom = ctx->Pixel.ZoomX!=1.0 || ctx->Pixel.ZoomY!=1.0;

   assert(image);
   assert(image->Format == GL_DEPTH_COMPONENT);

   width = image->Width;
   height = image->Height;

   /* Color or index */
   if (ctx->Visual->RGBAflag) {
      GLint r = (GLint) (ctx->Current.RasterColor[0] * 255.0F);
      GLint g = (GLint) (ctx->Current.RasterColor[1] * 255.0F);
      GLint b = (GLint) (ctx->Current.RasterColor[2] * 255.0F);
      GLint a = (GLint) (ctx->Current.RasterColor[3] * 255.0F);
      GLint i;
      for (i=0; i<width; i++) {
	 rgba[i][RCOMP] = r;
	 rgba[i][GCOMP] = g;
	 rgba[i][BCOMP] = b;
	 rgba[i][ACOMP] = a;
      }
   }
   else {
      GLint i;
      for (i=0;i<width;i++) {
	 ispan[i] = ctx->Current.RasterIndex;
      }
   }

   if (image->Type==GL_UNSIGNED_SHORT && sizeof(GLdepth)==sizeof(GLushort)
       && !bias_or_scale && !zoom && ctx->Visual->RGBAflag) {
      /* Special case: directly write 16-bit depth values */
      GLint j;
      for (j=0;j<height;j++,y++) {
	 GLdepth *zptr = (GLdepth *) image->Data + j * width;
	 gl_write_rgba_span( ctx, width, x, y, zptr, rgba, GL_BITMAP );
      }
   }
   else if (image->Type==GL_UNSIGNED_INT && sizeof(GLdepth)==sizeof(GLuint)
       && !bias_or_scale && !zoom && ctx->Visual->RGBAflag) {
      /* Special case: directly write 32-bit depth values */
      GLint i, j;
      /* Compute shift value to scale 32-bit uints down to depth values. */
      GLuint shift = 0;
      GLuint max = MAX_DEPTH;
      while ((max&0x80000000)==0) {
	 max = max << 1;
	 shift++;
      }
      for (j=0;j<height;j++,y++) {
	 GLdepth zspan[MAX_WIDTH];
	 GLuint *zptr = (GLuint *) image->Data + j * width;
	 for (i=0;i<width;i++) {
	    zspan[i] = zptr[i] >> shift;
	 }
	 gl_write_rgba_span( ctx, width, x, y, zspan, rgba, GL_BITMAP );
      }
   }
   else {
      /* General case (slower) */
      GLint i, j;

      /* process image row by row */
      for (i=0;i<height;i++,y++) {
	 GLfloat depth[MAX_WIDTH];
	 GLdepth zspan[MAX_WIDTH];

	 switch (image->Type) {
	    case GL_UNSIGNED_SHORT:
	       {
		  GLushort *src = (GLushort *) image->Data + i * width;
		  for (j=0;j<width;j++) {
		     depth[j] = USHORT_TO_FLOAT( *src++ );
		  }
	       }
	       break;
	    case GL_UNSIGNED_INT:
	       {
		  GLuint *src = (GLuint *) image->Data + i * width;
		  for (j=0;j<width;j++) {
		     depth[j] = UINT_TO_FLOAT( *src++ );
		  }
	       }
	       break;
	    case GL_FLOAT:
	       {
		  GLfloat *src = (GLfloat *) image->Data + i * width;
		  for (j=0;j<width;j++) {
		     depth[j] = *src++;
		  }
	       }
	       break;
	    default:
	       gl_problem(ctx, "Bad type in draw_depth_pixels");
	       return;
	 }

	 /* apply depth scale and bias */
	 if (ctx->Pixel.DepthScale!=1.0 || ctx->Pixel.DepthBias!=0.0) {
	    for (j=0;j<width;j++) {
	       depth[j] = depth[j] * ctx->Pixel.DepthScale + ctx->Pixel.DepthBias;
	    }
	 }

	 /* clamp depth values to [0,1] and convert from floats to integers */
	 for (j=0;j<width;j++) {
	    zspan[j] = (GLdepth) (CLAMP( depth[j], 0.0F, 1.0F ) * DEPTH_SCALE);
	 }

	 if (ctx->Visual->RGBAflag) {
	    if (zoom) {
#ifndef __STORM__
	       gl_write_zoomed_rgba_span( ctx, width, x, y, zspan,
					  rgba, desty );
#else
	       gl_write_zoomed_rgba_span( ctx, width, x, y, zspan,
					  (CONST GLubyte(*)[4])rgba, desty );
#endif
	    }
	    else {
	       gl_write_rgba_span( ctx, width, x, y, zspan, rgba, GL_BITMAP );
	    }
	 }
	 else {
	    if (zoom) {
	       gl_write_zoomed_index_span( ctx, width, x, y, zspan,
					   ispan, GL_BITMAP );
	    }
	    else {
	       gl_write_index_span( ctx, width, x, y, zspan, ispan, GL_BITMAP );
	    }
	 }

      }
   }
}



/* Simple unpacking parameters: */
static struct gl_pixelstore_attrib NoUnpack = {
   1,            /* Alignment */
   0,            /* RowLength */
   0,            /* SkipPixels */
   0,            /* SkipRows */
   0,            /* ImageHeight */
   0,            /* SkipImages */
   GL_FALSE,     /* SwapBytes */
   GL_FALSE      /* LsbFirst */
};


/*
 * Do glDrawPixels of RGBA pixels.
 */
static void draw_rgba_pixels( GLcontext *ctx, GLint x, GLint y,
			      const struct gl_image *image )
{
   GLint width, height;
   GLint i, j;
   const GLint desty = y;
   GLdepth zspan[MAX_WIDTH];
   GLboolean quickDraw;
   const GLboolean zoom = ctx->Pixel.ZoomX!=1.0 || ctx->Pixel.ZoomY!=1.0;

   assert(image);

   /* Try an optimized glDrawPixels first */
   if (gl_direct_DrawPixels(ctx, &NoUnpack, image->Width, image->Height,
			    image->Format, image->Type, image->Data ))
      return;

   width = image->Width;
   height = image->Height;

   /* Fragment depth values */
   if (ctx->Depth.Test) {
      /* fill in array of z values */
      GLdepth z = (GLdepth) (ctx->Current.RasterPos[2] * DEPTH_SCALE);
      for (i=0;i<width;i++) {
	 zspan[i] = z;
      }
   }

   if (ctx->RasterMask==0 && !zoom && x>=0 && y>=0
       && x+width<=ctx->Buffer->Width && y+height<=ctx->Buffer->Height) {
      quickDraw = GL_TRUE;
   }
   else {
      quickDraw = GL_FALSE;
   }

   {
      /* General solution */
      GLboolean r_flag, g_flag, b_flag, a_flag, l_flag;
      GLuint components;
      DEFARRAY(GLfloat, rf, MAX_WIDTH);
      DEFARRAY(GLfloat, gf, MAX_WIDTH);
      DEFARRAY(GLfloat, bf, MAX_WIDTH);
      DEFARRAY(GLfloat, af, MAX_WIDTH);
      GLubyte rgba[MAX_WIDTH][4];

      r_flag = g_flag = b_flag = a_flag = l_flag = GL_FALSE;
      switch (image->Format) {
	 case GL_RED:
	    r_flag = GL_TRUE;
	    components = 1;
	    break;
	 case GL_GREEN:
	    g_flag = GL_TRUE;
	    components = 1;
	    break;
	 case GL_BLUE:
	    b_flag = GL_TRUE;
	    components = 1;
	    break;
	 case GL_ALPHA:
	    a_flag = GL_TRUE;
	    components = 1;
	    break;
	 case GL_RGB:
	    r_flag = g_flag = b_flag = GL_TRUE;
	    components = 3;
	    break;
	 case GL_LUMINANCE:
	    l_flag = GL_TRUE;
	    components = 1;
	    break;
	 case GL_LUMINANCE_ALPHA:
	    l_flag = a_flag = GL_TRUE;
	    components = 2;
	    break;
	 case GL_RGBA:
	    r_flag = g_flag = b_flag = a_flag = GL_TRUE;
	    components = 4;
	    break;
	 default:
	    gl_problem(ctx, "Bad type in draw_rgba_pixels");
	    goto cleanup;
      }

      /* process the image row by row */
      for (i=0;i<height;i++,y++) {
	 /* convert to floats */
	 switch (image->Type) {
	    case GL_UNSIGNED_BYTE:
	       {
		  GLubyte *src = (GLubyte *) image->Data + i * width * components;
		  for (j=0;j<width;j++) {
		     if (l_flag) {
			rf[j] = gf[j] = bf[j] = UBYTE_TO_FLOAT(*src++);
		     }
		     else {
			rf[j] = r_flag ? UBYTE_TO_FLOAT(*src++) : 0.0;
			gf[j] = g_flag ? UBYTE_TO_FLOAT(*src++) : 0.0;
			bf[j] = b_flag ? UBYTE_TO_FLOAT(*src++) : 0.0;
		     }
		     af[j] = a_flag ? UBYTE_TO_FLOAT(*src++) : 1.0;
		  }
	       }
	       break;
	    case GL_FLOAT:
	       {
		  GLfloat *src = (GLfloat *) image->Data + i * width * components;
		  for (j=0;j<width;j++) {
		     if (l_flag) {
			rf[j] = gf[j] = bf[j] = *src++;
		     }
		     else {
			rf[j] = r_flag ? *src++ : 0.0;
			gf[j] = g_flag ? *src++ : 0.0;
			bf[j] = b_flag ? *src++ : 0.0;
		     }
		     af[j] = a_flag ? *src++ : 1.0;
		  }
	       }
	       break;
	    default:
	       gl_problem( ctx, "draw_rgba_pixels type" );
	       goto cleanup;
	 }

	 /* apply scale and bias */
	 if (ctx->Pixel.ScaleOrBiasRGBA) {
	    gl_scale_and_bias_color(ctx, width, rf, gf, bf, af);
	 }

	 /* apply pixel mappings */
	 if (ctx->Pixel.MapColorFlag) {
	    gl_map_color(ctx, width, rf, gf, bf, af);
	 }

	 /* convert to integers */
	 for (j=0;j<width;j++) {
	    rgba[j][RCOMP] = (GLint) (rf[j] * 255.0F);
	    rgba[j][GCOMP] = (GLint) (gf[j] * 255.0F);
	    rgba[j][BCOMP] = (GLint) (bf[j] * 255.0F);
	    rgba[j][ACOMP] = (GLint) (af[j] * 255.0F);
	 }

	 /* write to frame buffer */
	 if (quickDraw) {
#ifndef __STORM__
	    (*ctx->Driver.WriteRGBASpan)( ctx, width, x, y, rgba, NULL);
#else
	    (*ctx->Driver.WriteRGBASpan)( ctx, width, x, y, (CONST GLubyte(*)[4])rgba, NULL);
#endif
	 }
	 else if (zoom) {
#ifndef __STORM__
	    gl_write_zoomed_rgba_span( ctx, width, x, y, zspan, rgba, desty );
#else
	    gl_write_zoomed_rgba_span( ctx, width, x, y, zspan, (CONST GLubyte(*)[4])rgba, desty );
#endif
	 }
	 else {
	    gl_write_rgba_span( ctx, (GLuint) width, x, y, zspan, rgba, GL_BITMAP);
	 }
      }
cleanup:
      UNDEFARRAY(rf);
      UNDEFARRAY(gf);
      UNDEFARRAY(bf);
      UNDEFARRAY(af);
   }
}



/*
 * Execute glDrawPixels
 */
void gl_DrawPixels( GLcontext* ctx, struct gl_image *image )
{
   if (INSIDE_BEGIN_END(ctx)) {
      gl_error( ctx, GL_INVALID_OPERATION, "glDrawPixels" );
      return;
   }

   if (gl_image_error_test( ctx, image, "glDrawPixels" ))
      return;

   if (ctx->RenderMode==GL_RENDER) {
      GLint x, y;
      if (!ctx->Current.RasterPosValid) {
	 return;
      }

      x = (GLint) (ctx->Current.RasterPos[0] + 0.5F);
      y = (GLint) (ctx->Current.RasterPos[1] + 0.5F);

      switch (image->Format) {
	 case GL_COLOR_INDEX:
	    draw_index_pixels( ctx, x, y, image );
	    break;
	 case GL_STENCIL_INDEX:
	    draw_stencil_pixels( ctx, x, y, image );
	    break;
	 case GL_DEPTH_COMPONENT:
	    draw_depth_pixels( ctx, x, y, image );
	    break;
	 case GL_RED:
	 case GL_GREEN:
	 case GL_BLUE:
	 case GL_ALPHA:
	 case GL_RGB:
	 case GL_LUMINANCE:
	 case GL_LUMINANCE_ALPHA:
	 case GL_RGBA:
	    draw_rgba_pixels( ctx, x, y, image );
	    break;
	 default:
	    gl_error( ctx, GL_INVALID_ENUM, "glDrawPixels" );
	    return;
      }
   }
   else if (ctx->RenderMode==GL_FEEDBACK) {
      if (ctx->Current.RasterPosValid) {
	 GLfloat color[4], texcoord[4], invq;
	 color[0] = (GLfloat) ctx->Current.ByteColor[0] / 255.0;
	 color[1] = (GLfloat) ctx->Current.ByteColor[1] / 255.0;
	 color[2] = (GLfloat) ctx->Current.ByteColor[2] / 255.0;
	 color[3] = (GLfloat) ctx->Current.ByteColor[3] / 255.0;
	 invq = 1.0F / ctx->Current.TexCoord[3];
	 texcoord[0] = ctx->Current.TexCoord[0] * invq;
	 texcoord[1] = ctx->Current.TexCoord[1] * invq;
	 texcoord[2] = ctx->Current.TexCoord[2] * invq;
	 texcoord[3] = ctx->Current.TexCoord[3];
	 FEEDBACK_TOKEN( ctx, (GLfloat) (GLint) GL_DRAW_PIXEL_TOKEN );
	 gl_feedback_vertex( ctx,
			     ctx->Current.RasterPos[0],
			     ctx->Current.RasterPos[1],
			     ctx->Current.RasterPos[2],
			     ctx->Current.RasterPos[3],
			     color, ctx->Current.Index, texcoord );
      }
   }
   else if (ctx->RenderMode==GL_SELECT) {
      if (ctx->Current.RasterPosValid) {
	 gl_update_hitflag( ctx, ctx->Current.RasterPos[2] );
      }
   }
}