src/mesa/swrast/s_bitmap.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.5.2
   4  *
   5  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 /**
  26  * \file swrast/s_bitmap.c
  27  * \brief glBitmap rendering.
  28  * \author Brian Paul
  29  */
  30
  31 #include "glheader.h"
  32 #include "bufferobj.h"
  33 #include "image.h"
  34 #include "macros.h"
  35 #include "pixel.h"
  36
  37 #include "s_context.h"
  38 #include "s_span.h"
  39
  40
  41
  42 /**
  43  * Render a bitmap.
  44  * Called via ctx->Driver.Bitmap()
  45  * All parameter error checking will have been done before this is called.
  46  */
  47 void
  48 _swrast_Bitmap( GLcontext *ctx, GLint px, GLint py,
  49                 GLsizei width, GLsizei height,
  50                 const struct gl_pixelstore_attrib *unpack,
  51                 const GLubyte *bitmap )
  52 {
  53    SWcontext *swrast = SWRAST_CONTEXT(ctx);
  54    GLint row, col;
  55    GLuint count = 0;
  56    SWspan span;
  57
  58    ASSERT(ctx->RenderMode == GL_RENDER);
  59
  60    if (unpack->BufferObj->Name) {
  61       /* unpack from PBO */
  62       GLubyte *buf;
  63       if (!_mesa_validate_pbo_access(2, unpack, width, height, 1,
  64                                      GL_COLOR_INDEX, GL_BITMAP,
  65                                      (GLvoid *) bitmap)) {
  66          _mesa_error(ctx, GL_INVALID_OPERATION,"glBitmap(invalid PBO access)");
  67          return;
  68       }
  69       buf = (GLubyte *) ctx->Driver.MapBuffer(ctx, GL_PIXEL_UNPACK_BUFFER_EXT,
  70                                               GL_READ_ONLY_ARB,
  71                                               unpack->BufferObj);
  72       if (!buf) {
  73          /* buffer is already mapped - that's an error */
  74          _mesa_error(ctx, GL_INVALID_OPERATION, "glBitmap(PBO is mapped)");
  75          return;
  76       }
  77       bitmap = ADD_POINTERS(buf, bitmap);
  78    }
  79
  80    RENDER_START(swrast,ctx);
  81
  82    if (SWRAST_CONTEXT(ctx)->NewState)
  83       _swrast_validate_derived( ctx );
  84
  85    INIT_SPAN(span, GL_BITMAP, width, 0, SPAN_XY);
  86    _swrast_span_default_attribs(ctx, &span);
  87
  88    for (row = 0; row < height; row++) {
  89       const GLubyte *src = (const GLubyte *) _mesa_image_address2d(unpack,
  90                  bitmap, width, height, GL_COLOR_INDEX, GL_BITMAP, row, 0);
  91
  92       if (unpack->LsbFirst) {
  93          /* Lsb first */
  94          GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
  95          for (col = 0; col < width; col++) {
  96             if (*src & mask) {
  97                span.array->x[count] = px + col;
  98                span.array->y[count] = py + row;
  99                count++;
 100             }
 101             if (mask == 128U) {
 102                src++;
 103                mask = 1U;
 104             }
 105             else {
 106                mask = mask << 1;
 107             }
 108          }
 109
 110          /* get ready for next row */
 111          if (mask != 1)
 112             src++;
 113       }
 114       else {
 115          /* Msb first */
 116          GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
 117          for (col = 0; col < width; col++) {
 118             if (*src & mask) {
 119                span.array->x[count] = px + col;
 120                span.array->y[count] = py + row;
 121                count++;
 122             }
 123             if (mask == 1U) {
 124                src++;
 125                mask = 128U;
 126             }
 127             else {
 128                mask = mask >> 1;
 129             }
 130          }
 131
 132          /* get ready for next row */
 133          if (mask != 128)
 134             src++;
 135       }
 136
 137       if (count + width >= MAX_WIDTH || row + 1 == height) {
 138          /* flush the span */
 139          span.end = count;
 140          if (ctx->Visual.rgbMode)
 141             _swrast_write_rgba_span(ctx, &span);
 142          else
 143             _swrast_write_index_span(ctx, &span);
 144          span.end = 0;
 145          count = 0;
 146       }
 147    }
 148
 149    RENDER_FINISH(swrast,ctx);
 150
 151    if (unpack->BufferObj->Name) {
 152       /* done with PBO so unmap it now */
 153       ctx->Driver.UnmapBuffer(ctx, GL_PIXEL_UNPACK_BUFFER_EXT,
 154                               unpack->BufferObj);
 155    }
 156 }
 157
 158
 159 #if 0
 160 /*
 161  * XXX this is another way to implement Bitmap.  Use horizontal runs of
 162  * fragments, initializing the mask array to indicate which fragments to
 163  * draw or skip.
 164  */
 165 void
 166 _swrast_Bitmap( GLcontext *ctx, GLint px, GLint py,
 167                 GLsizei width, GLsizei height,
 168                 const struct gl_pixelstore_attrib *unpack,
 169                 const GLubyte *bitmap )
 170 {
 171    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 172    GLint row, col;
 173    SWspan span;
 174
 175    ASSERT(ctx->RenderMode == GL_RENDER);
 176    ASSERT(bitmap);
 177
 178    RENDER_START(swrast,ctx);
 179
 180    if (SWRAST_CONTEXT(ctx)->NewState)
 181       _swrast_validate_derived( ctx );
 182
 183    INIT_SPAN(span, GL_BITMAP, width, 0, SPAN_MASK);
 184    _swrast_span_default_attribs(ctx, &span);
 185
 186    /*span.arrayMask |= SPAN_MASK;*/  /* we'll init span.mask[] */
 187    span.x = px;
 188    span.y = py;
 189    /*span.end = width;*/
 190
 191    for (row=0; row<height; row++, span.y++) {
 192       const GLubyte *src = (const GLubyte *) _mesa_image_address2d(unpack,
 193                  bitmap, width, height, GL_COLOR_INDEX, GL_BITMAP, row, 0);
 194
 195       if (unpack->LsbFirst) {
 196          /* Lsb first */
 197          GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
 198          for (col=0; col<width; col++) {
 199             span.array->mask[col] = (*src & mask) ? GL_TRUE : GL_FALSE;
 200             if (mask == 128U) {
 201                src++;
 202                mask = 1U;
 203             }
 204             else {
 205                mask = mask << 1;
 206             }
 207          }
 208
 209          if (ctx->Visual.rgbMode)
 210             _swrast_write_rgba_span(ctx, &span);
 211          else
 212             _swrast_write_index_span(ctx, &span);
 213
 214          /* get ready for next row */
 215          if (mask != 1)
 216             src++;
 217       }
 218       else {
 219          /* Msb first */
 220          GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
 221          for (col=0; col<width; col++) {
 222             span.array->mask[col] = (*src & mask) ? GL_TRUE : GL_FALSE;
 223             if (mask == 1U) {
 224                src++;
 225                mask = 128U;
 226             }
 227             else {
 228                mask = mask >> 1;
 229             }
 230          }
 231
 232          if (ctx->Visual.rgbMode)
 233             _swrast_write_rgba_span(ctx, &span);
 234          else
 235             _swrast_write_index_span(ctx, &span);
 236
 237          /* get ready for next row */
 238          if (mask != 128)
 239             src++;
 240       }
 241    }
 242
 243    RENDER_FINISH(swrast,ctx);
 244 }
 245 #endif