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