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
  87    _swrast_span_default_color(ctx, &span);
  88    _swrast_span_default_secondary_color(ctx, &span);
  89    if (ctx->Depth.Test)
  90       _swrast_span_default_z(ctx, &span);
  91    if (swrast->_FogEnabled)
  92       _swrast_span_default_fog(ctx, &span);
  93    if (ctx->Texture._EnabledCoordUnits)
  94       _swrast_span_default_texcoords(ctx, &span);
  95
  96    for (row = 0; row < height; row++) {
  97       const GLubyte *src = (const GLubyte *) _mesa_image_address2d(unpack,
  98                  bitmap, width, height, GL_COLOR_INDEX, GL_BITMAP, row, 0);
  99
 100       if (unpack->LsbFirst) {
 101          /* Lsb first */
 102          GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
 103          for (col = 0; col < width; col++) {
 104             if (*src & mask) {
 105                span.array->x[count] = px + col;
 106                span.array->y[count] = py + row;
 107                count++;
 108             }
 109             if (mask == 128U) {
 110                src++;
 111                mask = 1U;
 112             }
 113             else {
 114                mask = mask << 1;
 115             }
 116          }
 117
 118          /* get ready for next row */
 119          if (mask != 1)
 120             src++;
 121       }
 122       else {
 123          /* Msb first */
 124          GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
 125          for (col = 0; col < width; col++) {
 126             if (*src & mask) {
 127                span.array->x[count] = px + col;
 128                span.array->y[count] = py + row;
 129                count++;
 130             }
 131             if (mask == 1U) {
 132                src++;
 133                mask = 128U;
 134             }
 135             else {
 136                mask = mask >> 1;
 137             }
 138          }
 139
 140          /* get ready for next row */
 141          if (mask != 128)
 142             src++;
 143       }
 144
 145       if (count + width >= MAX_WIDTH || row + 1 == height) {
 146          /* flush the span */
 147          span.end = count;
 148          if (ctx->Visual.rgbMode)
 149             _swrast_write_rgba_span(ctx, &span);
 150          else
 151             _swrast_write_index_span(ctx, &span);
 152          span.end = 0;
 153          count = 0;
 154       }
 155    }
 156
 157    RENDER_FINISH(swrast,ctx);
 158
 159    if (unpack->BufferObj->Name) {
 160       /* done with PBO so unmap it now */
 161       ctx->Driver.UnmapBuffer(ctx, GL_PIXEL_UNPACK_BUFFER_EXT,
 162                               unpack->BufferObj);
 163    }
 164 }
 165
 166
 167 #if 0
 168 /*
 169  * XXX this is another way to implement Bitmap.  Use horizontal runs of
 170  * fragments, initializing the mask array to indicate which fragments to
 171  * draw or skip.
 172  */
 173 void
 174 _swrast_Bitmap( GLcontext *ctx, GLint px, GLint py,
 175                 GLsizei width, GLsizei height,
 176                 const struct gl_pixelstore_attrib *unpack,
 177                 const GLubyte *bitmap )
 178 {
 179    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 180    GLint row, col;
 181    SWspan span;
 182
 183    ASSERT(ctx->RenderMode == GL_RENDER);
 184    ASSERT(bitmap);
 185
 186    RENDER_START(swrast,ctx);
 187
 188    if (SWRAST_CONTEXT(ctx)->NewState)
 189       _swrast_validate_derived( ctx );
 190
 191    INIT_SPAN(span, GL_BITMAP, width, 0, SPAN_MASK);
 192
 193    /*span.arrayMask |= SPAN_MASK;*/  /* we'll init span.mask[] */
 194    span.x = px;
 195    span.y = py;
 196    /*span.end = width;*/
 197
 198    _swrast_span_default_color(ctx, &span);
 199    if (ctx->Depth.Test)
 200       _swrast_span_default_z(ctx, &span);
 201    if (swrast->_FogEnabled)
 202       _swrast_span_default_fog(ctx, &span);
 203    if (ctx->Texture._EnabledCoordUnits)
 204       _swrast_span_default_texcoords(ctx, &span);
 205
 206    for (row=0; row<height; row++, span.y++) {
 207       const GLubyte *src = (const GLubyte *) _mesa_image_address2d(unpack,
 208                  bitmap, width, height, GL_COLOR_INDEX, GL_BITMAP, row, 0);
 209
 210       if (unpack->LsbFirst) {
 211          /* Lsb first */
 212          GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
 213          for (col=0; col<width; col++) {
 214             span.array->mask[col] = (*src & mask) ? GL_TRUE : GL_FALSE;
 215             if (mask == 128U) {
 216                src++;
 217                mask = 1U;
 218             }
 219             else {
 220                mask = mask << 1;
 221             }
 222          }
 223
 224          if (ctx->Visual.rgbMode)
 225             _swrast_write_rgba_span(ctx, &span);
 226          else
 227             _swrast_write_index_span(ctx, &span);
 228
 229          /* get ready for next row */
 230          if (mask != 1)
 231             src++;
 232       }
 233       else {
 234          /* Msb first */
 235          GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
 236          for (col=0; col<width; col++) {
 237             span.array->mask[col] = (*src & mask) ? GL_TRUE : GL_FALSE;
 238             if (mask == 1U) {
 239                src++;
 240                mask = 128U;
 241             }
 242             else {
 243                mask = mask >> 1;
 244             }
 245          }
 246
 247          if (ctx->Visual.rgbMode)
 248             _swrast_write_rgba_span(ctx, &span);
 249          else
 250             _swrast_write_index_span(ctx, &span);
 251
 252          /* get ready for next row */
 253          if (mask != 128)
 254             src++;
 255       }
 256    }
 257
 258    RENDER_FINISH(swrast,ctx);
 259 }
 260 #endif