histogram.c

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][ACOMP] & 0xf) << 12)
                      | ((rgba[i][RCOMP] & 0xf) <<  8)
                      | ((rgba[i][GCOMP] & 0xf) <<  4)
                      | ((rgba[i][BCOMP] & 0xf)      );
            }
         }
         else {
            GLushort *dst = (GLushort *) destination;
            GLuint i;
            ASSERT(format == GL_ABGR_EXT);
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][RCOMP] & 0xf) << 12)
                      | ((rgba[i][GCOMP] & 0xf) <<  8)
                      | ((rgba[i][BCOMP] & 0xf) <<  4)
                      | ((rgba[i][ACOMP] & 0xf)      );
            }
         }
         break;
      case GL_UNSIGNED_SHORT_5_5_5_1:
         if (format == GL_RGBA) {
            GLushort *dst = (GLushort *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][RCOMP] & 0x1f) << 11)
                      | ((rgba[i][GCOMP] & 0x1f) <<  6)
                      | ((rgba[i][BCOMP] & 0x1f) <<  1)
                      | ((rgba[i][ACOMP] & 0x1)       );
            }
         }
         else if (format == GL_BGRA) {
            GLushort *dst = (GLushort *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][BCOMP] & 0x1f) << 11)
                      | ((rgba[i][GCOMP] & 0x1f) <<  6)
                      | ((rgba[i][RCOMP] & 0x1f) <<  1)
                      | ((rgba[i][ACOMP] & 0x1)       );
            }
         }
         else {
            GLushort *dst = (GLushort *) destination;
            GLuint i;
            ASSERT(format == GL_ABGR_EXT);
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][ACOMP] & 0x1f) << 11)
                      | ((rgba[i][BCOMP] & 0x1f) <<  6)
                      | ((rgba[i][GCOMP] & 0x1f) <<  1)
                      | ((rgba[i][RCOMP] & 0x1)       );
            }
         }
         break;
      case GL_UNSIGNED_SHORT_1_5_5_5_REV:
         if (format == GL_RGBA) {
            GLushort *dst = (GLushort *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][ACOMP] & 0x1f) << 11)
                      | ((rgba[i][BCOMP] & 0x1f) <<  6)
                      | ((rgba[i][GCOMP] & 0x1f) <<  1)
                      | ((rgba[i][RCOMP] & 0x1)       );
            }
         }
         else if (format == GL_BGRA) {
            GLushort *dst = (GLushort *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][ACOMP] & 0x1f) << 11)
                      | ((rgba[i][RCOMP] & 0x1f) <<  6)
                      | ((rgba[i][GCOMP] & 0x1f) <<  1)
                      | ((rgba[i][BCOMP] & 0x1)       );
            }
         }
         else {
            GLushort *dst = (GLushort *) destination;
            GLuint i;
            ASSERT(format == GL_ABGR_EXT);
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][RCOMP] & 0x1f) << 11)
                      | ((rgba[i][GCOMP] & 0x1f) <<  6)
                      | ((rgba[i][BCOMP] & 0x1f) <<  1)
                      | ((rgba[i][ACOMP] & 0x1)       );
            }
         }
         break;
      case GL_UNSIGNED_INT_8_8_8_8:
         if (format == GL_RGBA) {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][RCOMP] & 0xff) << 24)
                      | ((rgba[i][GCOMP] & 0xff) << 16)
                      | ((rgba[i][BCOMP] & 0xff) <<  8)
                      | ((rgba[i][ACOMP] & 0xff)      );
            }
         }
         else if (format == GL_BGRA) {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][BCOMP] & 0xff) << 24)
                      | ((rgba[i][GCOMP] & 0xff) << 16)
                      | ((rgba[i][RCOMP] & 0xff) <<  8)
                      | ((rgba[i][ACOMP] & 0xff)      );
            }
         }
         else {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            ASSERT(format == GL_ABGR_EXT);
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][ACOMP] & 0xff) << 24)
                      | ((rgba[i][BCOMP] & 0xff) << 16)
                      | ((rgba[i][GCOMP] & 0xff) <<  8)
                      | ((rgba[i][RCOMP] & 0xff)      );
            }
         }
         break;
      case GL_UNSIGNED_INT_8_8_8_8_REV:
         if (format == GL_RGBA) {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][ACOMP] & 0xff) << 24)
                      | ((rgba[i][BCOMP] & 0xff) << 16)
                      | ((rgba[i][GCOMP] & 0xff) <<  8)
                      | ((rgba[i][RCOMP] & 0xff)      );
            }
         }
         else if (format == GL_BGRA) {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][ACOMP] & 0xff) << 24)
                      | ((rgba[i][RCOMP] & 0xff) << 16)
                      | ((rgba[i][GCOMP] & 0xff) <<  8)
                      | ((rgba[i][BCOMP] & 0xff)      );
            }
         }
         else {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            ASSERT(format == GL_ABGR_EXT);
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][RCOMP] & 0xff) << 24)
                      | ((rgba[i][GCOMP] & 0xff) << 16)
                      | ((rgba[i][BCOMP] & 0xff) <<  8)
                      | ((rgba[i][ACOMP] & 0xff)      );
            }
         }
         break;
      case GL_UNSIGNED_INT_10_10_10_2:
         if (format == GL_RGBA) {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][RCOMP] & 0x3ff) << 22)
                      | ((rgba[i][GCOMP] & 0x3ff) << 12)
                      | ((rgba[i][BCOMP] & 0x3ff) <<  2)
                      | ((rgba[i][ACOMP] & 0x3)        );
            }
         }
         else if (format == GL_BGRA) {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][BCOMP] & 0x3ff) << 22)
                      | ((rgba[i][GCOMP] & 0x3ff) << 12)
                      | ((rgba[i][RCOMP] & 0x3ff) <<  2)
                      | ((rgba[i][ACOMP] & 0x3)        );
            }
         }
         else {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            ASSERT(format == GL_ABGR_EXT);
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][ACOMP] & 0x3ff) << 22)
                      | ((rgba[i][BCOMP] & 0x3ff) << 12)
                      | ((rgba[i][GCOMP] & 0x3ff) <<  2)
                      | ((rgba[i][RCOMP] & 0x3)        );
            }
         }
         break;
      case GL_UNSIGNED_INT_2_10_10_10_REV:
         if (format == GL_RGBA) {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][ACOMP] & 0x3ff) << 22)
                      | ((rgba[i][BCOMP] & 0x3ff) << 12)
                      | ((rgba[i][GCOMP] & 0x3ff) <<  2)
                      | ((rgba[i][RCOMP] & 0x3)        );
            }
         }
         else if (format == GL_BGRA) {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][ACOMP] & 0x3ff) << 22)
                      | ((rgba[i][RCOMP] & 0x3ff) << 12)
                      | ((rgba[i][GCOMP] & 0x3ff) <<  2)
                      | ((rgba[i][BCOMP] & 0x3)        );
            }
         }
         else {
            GLuint *dst = (GLuint *) destination;
            GLuint i;
            ASSERT(format == GL_ABGR_EXT);
            for (i = 0; i < n; i++) {
               dst[i] = ((rgba[i][RCOMP] & 0x3ff) << 22)
                      | ((rgba[i][GCOMP] & 0x3ff) << 12)
                      | ((rgba[i][BCOMP] & 0x3ff) <<  2)
                      | ((rgba[i][ACOMP] & 0x3)        );
            }
         }
         break;
      default:
         _mesa_problem(ctx, "Bad type in pack_histogram");
   }

#undef PACK_MACRO
}


/*
 * Given an internalFormat token passed to glHistogram or glMinMax,
 * return the corresponding base format.
 * Return -1 if invalid token.
 */
static GLint
base_histogram_format( GLenum format )
{
   switch (format) {
      case GL_ALPHA:
      case GL_ALPHA4:
      case GL_ALPHA8:
      case GL_ALPHA12:
      case GL_ALPHA16:
         return GL_ALPHA;
      case GL_LUMINANCE:
      case GL_LUMINANCE4:
      case GL_LUMINANCE8:
      case GL_LUMINANCE12:
      case GL_LUMINANCE16:
         return GL_LUMINANCE;
      case GL_LUMINANCE_ALPHA:
      case GL_LUMINANCE4_ALPHA4:
      case GL_LUMINANCE6_ALPHA2:
      case GL_LUMINANCE8_ALPHA8:
      case GL_LUMINANCE12_ALPHA4:
      case GL_LUMINANCE12_ALPHA12:
      case GL_LUMINANCE16_ALPHA16:
         return GL_LUMINANCE_ALPHA;
      case GL_RGB:
      case GL_R3_G3_B2:
      case GL_RGB4:
      case GL_RGB5:
      case GL_RGB8:
      case GL_RGB10:
      case GL_RGB12:
      case GL_RGB16:
         return GL_RGB;
      case GL_RGBA:
      case GL_RGBA2:
      case GL_RGBA4:
      case GL_RGB5_A1:
      case GL_RGBA8:
      case GL_RGB10_A2:
      case GL_RGBA12:
      case GL_RGBA16:
         return GL_RGBA;
      default:
         return -1;  /* error */
   }
}



/**********************************************************************
 * API functions
 */


void GLAPIENTRY
_mesa_GetMinmax(GLenum target, GLboolean reset, GLenum format, GLenum type, GLvoid *values)
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);

   if (!ctx->Extensions.EXT_histogram && !ctx->Extensions.ARB_imaging) {
      _mesa_error(ctx, GL_INVALID_OPERATION, "glGetMinmax");
      return;
   }

   if (target != GL_MINMAX) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glGetMinmax(target)");
      return;
   }

   if (format != GL_RED &&
       format != GL_GREEN &&
       format != GL_BLUE &&
       format != GL_ALPHA &&
       format != GL_RGB &&
       format != GL_BGR &&
       format != GL_RGBA &&
       format != GL_BGRA &&
       format != GL_ABGR_EXT &&
       format != GL_LUMINANCE &&
       format != GL_LUMINANCE_ALPHA) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glGetMinMax(format)");
   }

   if (!_mesa_is_legal_format_and_type(ctx, format, type)) {
      _mesa_error(ctx, GL_INVALID_OPERATION, "glGetMinmax(format or type)");
      return;
   }

   if (ctx->Pack.BufferObj->Name) {
      /* pack min/max values into a PBO */
      GLubyte *buf;
      if (!_mesa_validate_pbo_access(1, &ctx->Pack, 2, 1, 1,
                                     format, type, values)) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glGetMinMax(invalid PBO access)");
         return;
      }
      buf = (GLubyte *) ctx->Driver.MapBuffer(ctx, GL_PIXEL_PACK_BUFFER_EXT,
                                              GL_WRITE_ONLY_ARB,
                                              ctx->Pack.BufferObj);
      if (!buf) {
         /* buffer is already mapped - that's an error */
         _mesa_error(ctx, GL_INVALID_OPERATION,"glGetMinMax(PBO is mapped)");
         return;
      }
      values = ADD_POINTERS(buf, values);
   }
   else if (!values) {
      /* not an error */
      return;
   }

   {
      GLfloat minmax[2][4];
      minmax[0][RCOMP] = CLAMP(ctx->MinMax.Min[RCOMP], 0.0F, 1.0F);
      minmax[0][GCOMP] = CLAMP(ctx->MinMax.Min[GCOMP], 0.0F, 1.0F);
      minmax[0][BCOMP] = CLAMP(ctx->MinMax.Min[BCOMP], 0.0F, 1.0F);
      minmax[0][ACOMP] = CLAMP(ctx->MinMax.Min[ACOMP], 0.0F, 1.0F);
      minmax[1][RCOMP] = CLAMP(ctx->MinMax.Max[RCOMP], 0.0F, 1.0F);
      minmax[1][GCOMP] = CLAMP(ctx->MinMax.Max[GCOMP], 0.0F, 1.0F);
      minmax[1][BCOMP] = CLAMP(ctx->MinMax.Max[BCOMP], 0.0F, 1.0F);
      minmax[1][ACOMP] = CLAMP(ctx->MinMax.Max[ACOMP], 0.0F, 1.0F);
      _mesa_pack_rgba_span_float(ctx, 2, (CONST GLfloat (*)[4]) minmax,
                                 format, type, values, &ctx->Pack, 0);
   }

   if (ctx->Pack.BufferObj->Name) {
      ctx->Driver.UnmapBuffer(ctx, GL_PIXEL_PACK_BUFFER_EXT,
                              ctx->Pack.BufferObj);
   }

   if (reset) {
      _mesa_ResetMinmax(GL_MINMAX);
   }
}


void GLAPIENTRY
_mesa_GetHistogram(GLenum target, GLboolean reset, GLenum format, GLenum type, GLvoid *values)
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);

   if (!ctx->Extensions.EXT_histogram && !ctx->Extensions.ARB_imaging) {
      _mesa_error(ctx, GL_INVALID_OPERATION, "glGetHistogram");
      return;
   }

   if (target != GL_HISTOGRAM) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glGetHistogram(target)");
      return;
   }

   if (format != GL_RED &&
       format != GL_GREEN &&
       format != GL_BLUE &&
       format != GL_ALPHA &&
       format != GL_RGB &&
       format != GL_BGR &&
       format != GL_RGBA &&
       format != GL_BGRA &&
       format != GL_ABGR_EXT &&
       format != GL_LUMINANCE &&
       format != GL_LUMINANCE_ALPHA) {