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