convolve.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

}


void GLAPIENTRY
_mesa_GetSeparableFilter(GLenum target, GLenum format, GLenum type,
                         GLvoid *row, GLvoid *column, GLvoid *span)
{
   const GLint colStart = MAX_CONVOLUTION_WIDTH * 4;
   struct gl_convolution_attrib *filter;
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END(ctx);

   if (ctx->NewState) {
      _mesa_update_state(ctx);
   }

   if (target != GL_SEPARABLE_2D) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glGetSeparableFilter(target)");
      return;
   }

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

   if (format == GL_COLOR_INDEX ||
       format == GL_STENCIL_INDEX ||
       format == GL_DEPTH_COMPONENT ||
       format == GL_INTENSITY ||
       type == GL_BITMAP) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glGetConvolutionFilter(format or type)");
      return;
   }

   filter = &ctx->Separable2D;

   if (ctx->Pack.BufferObj->Name) {
      /* Pack filter into PBO */
      GLubyte *buf;
      if (!_mesa_validate_pbo_access(1, &ctx->Pack, filter->Width, 1, 1,
                                     format, type, row)) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glGetSeparableFilter(invalid PBO access, width)");
         return;
      }
      if (!_mesa_validate_pbo_access(1, &ctx->Pack, filter->Height, 1, 1,
                                     format, type, column)) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glGetSeparableFilter(invalid PBO access, height)");
         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,
                     "glGetSeparableFilter(PBO is mapped)");
         return;
      }
      row = ADD_POINTERS(buf, row);
      column = ADD_POINTERS(buf, column);
   }

   /* Row filter */
   if (row) {
      GLvoid *dst = _mesa_image_address1d(&ctx->Pack, row, filter->Width,
                                          format, type, 0);
      _mesa_pack_rgba_span_float(ctx, filter->Width,
                                 (GLfloat (*)[4]) filter->Filter,
                                 format, type, dst, &ctx->Pack, 0x0);
   }

   /* Column filter */
   if (column) {
      GLvoid *dst = _mesa_image_address1d(&ctx->Pack, column, filter->Height,
                                          format, type, 0);
      GLfloat (*src)[4] = (GLfloat (*)[4]) (filter->Filter + colStart);
      _mesa_pack_rgba_span_float(ctx, filter->Height, src,
                                 format, type, dst, &ctx->Pack, 0x0);
   }

   (void) span;  /* unused at this time */

   if (ctx->Pack.BufferObj->Name) {
      /* Pack filter into PBO */
      ctx->Driver.UnmapBuffer(ctx, GL_PIXEL_UNPACK_BUFFER_EXT,
                              ctx->Unpack.BufferObj);
   }
}


void GLAPIENTRY
_mesa_SeparableFilter2D(GLenum target, GLenum internalFormat, GLsizei width, GLsizei height, GLenum format, GLenum type, const GLvoid *row, const GLvoid *column)
{
   const GLint colStart = MAX_CONVOLUTION_WIDTH * 4;
   GLint baseFormat;
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);

   if (target != GL_SEPARABLE_2D) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glSeparableFilter2D(target)");
      return;
   }

   baseFormat = base_filter_format(internalFormat);
   if (baseFormat < 0 || baseFormat == GL_COLOR_INDEX) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glSeparableFilter2D(internalFormat)");
      return;
   }

   if (width < 0 || width > MAX_CONVOLUTION_WIDTH) {
      _mesa_error(ctx, GL_INVALID_VALUE, "glSeparableFilter2D(width)");
      return;
   }
   if (height < 0 || height > MAX_CONVOLUTION_HEIGHT) {
      _mesa_error(ctx, GL_INVALID_VALUE, "glSeparableFilter2D(height)");
      return;
   }

   if (!_mesa_is_legal_format_and_type(ctx, format, type)) {
      _mesa_error(ctx, GL_INVALID_OPERATION, "glSeparableFilter2D(format or type)");
      return;
   }

   if (format == GL_COLOR_INDEX ||
       format == GL_STENCIL_INDEX ||
       format == GL_DEPTH_COMPONENT ||
       format == GL_INTENSITY ||
       type == GL_BITMAP) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glSeparableFilter2D(format or type)");
      return;
   }

   ctx->Separable2D.Format = format;
   ctx->Separable2D.InternalFormat = internalFormat;
   ctx->Separable2D.Width = width;
   ctx->Separable2D.Height = height;

   if (ctx->Unpack.BufferObj->Name) {
      /* unpack filter from PBO */
      GLubyte *buf;
      if (!_mesa_validate_pbo_access(1, &ctx->Unpack, width, 1, 1,
                                     format, type, row)) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glSeparableFilter2D(invalid PBO access, width)");
         return;
      }
      if (!_mesa_validate_pbo_access(1, &ctx->Unpack, height, 1, 1,
                                     format, type, column)) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glSeparableFilter2D(invalid PBO access, height)");
         return;
      }
      buf = (GLubyte *) ctx->Driver.MapBuffer(ctx, GL_PIXEL_UNPACK_BUFFER_EXT,
                                              GL_READ_ONLY_ARB,
                                              ctx->Unpack.BufferObj);
      if (!buf) {
         /* buffer is already mapped - that's an error */
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glSeparableFilter2D(PBO is mapped)");
         return;
      }
      row = ADD_POINTERS(buf, row);
      column = ADD_POINTERS(buf, column);
   }

   /* unpack row filter */
   if (row) {
      _mesa_unpack_color_span_float(ctx, width, GL_RGBA,
                                    ctx->Separable2D.Filter,
                                    format, type, row, &ctx->Unpack,
                                    0);  /* transferOps */

      _mesa_scale_and_bias_rgba(width,
                             (GLfloat (*)[4]) ctx->Separable2D.Filter,
                             ctx->Pixel.ConvolutionFilterScale[2][0],
                             ctx->Pixel.ConvolutionFilterScale[2][1],
                             ctx->Pixel.ConvolutionFilterScale[2][2],
                             ctx->Pixel.ConvolutionFilterScale[2][3],
                             ctx->Pixel.ConvolutionFilterBias[2][0],
                             ctx->Pixel.ConvolutionFilterBias[2][1],
                             ctx->Pixel.ConvolutionFilterBias[2][2],
                             ctx->Pixel.ConvolutionFilterBias[2][3]);
   }

   /* unpack column filter */
   if (column) {
      _mesa_unpack_color_span_float(ctx, height, GL_RGBA,
                                    &ctx->Separable2D.Filter[colStart],
                                    format, type, column, &ctx->Unpack,
                                    0); /* transferOps */

      _mesa_scale_and_bias_rgba(height,
                       (GLfloat (*)[4]) (ctx->Separable2D.Filter + colStart),
                       ctx->Pixel.ConvolutionFilterScale[2][0],
                       ctx->Pixel.ConvolutionFilterScale[2][1],
                       ctx->Pixel.ConvolutionFilterScale[2][2],
                       ctx->Pixel.ConvolutionFilterScale[2][3],
                       ctx->Pixel.ConvolutionFilterBias[2][0],
                       ctx->Pixel.ConvolutionFilterBias[2][1],
                       ctx->Pixel.ConvolutionFilterBias[2][2],
                       ctx->Pixel.ConvolutionFilterBias[2][3]);
   }

   if (ctx->Unpack.BufferObj->Name) {
      ctx->Driver.UnmapBuffer(ctx, GL_PIXEL_UNPACK_BUFFER_EXT,
                              ctx->Unpack.BufferObj);
   }

   ctx->NewState |= _NEW_PIXEL;
}


/**********************************************************************/
/***                   image convolution functions                  ***/
/**********************************************************************/

static void
convolve_1d_reduce(GLint srcWidth, const GLfloat src[][4],
                   GLint filterWidth, const GLfloat filter[][4],
                   GLfloat dest[][4])
{
   GLint dstWidth;
   GLint i, n;

   if (filterWidth >= 1)
      dstWidth = srcWidth - (filterWidth - 1);
   else
      dstWidth = srcWidth;

   if (dstWidth <= 0)
      return;  /* null result */

   for (i = 0; i < dstWidth; i++) {
      GLfloat sumR = 0.0;
      GLfloat sumG = 0.0;
      GLfloat sumB = 0.0;
      GLfloat sumA = 0.0;
      for (n = 0; n < filterWidth; n++) {
         sumR += src[i + n][RCOMP] * filter[n][RCOMP];
         sumG += src[i + n][GCOMP] * filter[n][GCOMP];
         sumB += src[i + n][BCOMP] * filter[n][BCOMP];
         sumA += src[i + n][ACOMP] * filter[n][ACOMP];
      }
      dest[i][RCOMP] = sumR;
      dest[i][GCOMP] = sumG;
      dest[i][BCOMP] = sumB;
      dest[i][ACOMP] = sumA;
   }
}


static void
convolve_1d_constant(GLint srcWidth, const GLfloat src[][4],
                     GLint filterWidth, const GLfloat filter[][4],
                     GLfloat dest[][4],
                     const GLfloat borderColor[4])
{
   const GLint halfFilterWidth = filterWidth / 2;
   GLint i, n;

   for (i = 0; i < srcWidth; i++) {
      GLfloat sumR = 0.0;
      GLfloat sumG = 0.0;
      GLfloat sumB = 0.0;
      GLfloat sumA = 0.0;
      for (n = 0; n < filterWidth; n++) {
         if (i + n < halfFilterWidth || i + n - halfFilterWidth >= srcWidth) {
            sumR += borderColor[RCOMP] * filter[n][RCOMP];
            sumG += borderColor[GCOMP] * filter[n][GCOMP];
            sumB += borderColor[BCOMP] * filter[n][BCOMP];
            sumA += borderColor[ACOMP] * filter[n][ACOMP];
         }
         else {
            sumR += src[i + n - halfFilterWidth][RCOMP] * filter[n][RCOMP];
            sumG += src[i + n - halfFilterWidth][GCOMP] * filter[n][GCOMP];
            sumB += src[i + n - halfFilterWidth][BCOMP] * filter[n][BCOMP];
            sumA += src[i + n - halfFilterWidth][ACOMP] * filter[n][ACOMP];
         }
      }
      dest[i][RCOMP] = sumR;
      dest[i][GCOMP] = sumG;
      dest[i][BCOMP] = sumB;
      dest[i][ACOMP] = sumA;
   }
}


static void
convolve_1d_replicate(GLint srcWidth, const GLfloat src[][4],
                      GLint filterWidth, const GLfloat filter[][4],
                      GLfloat dest[][4])
{
   const GLint halfFilterWidth = filterWidth / 2;
   GLint i, n;

   for (i = 0; i < srcWidth; i++) {
      GLfloat sumR = 0.0;
      GLfloat sumG = 0.0;
      GLfloat sumB = 0.0;
      GLfloat sumA = 0.0;
      for (n = 0; n < filterWidth; n++) {
         if (i + n < halfFilterWidth) {
            sumR += src[0][RCOMP] * filter[n][RCOMP];
            sumG += src[0][GCOMP] * filter[n][GCOMP];
            sumB += src[0][BCOMP] * filter[n][BCOMP];
            sumA += src[0][ACOMP] * filter[n][ACOMP];
         }
         else if (i + n - halfFilterWidth >= srcWidth) {
            sumR += src[srcWidth - 1][RCOMP] * filter[n][RCOMP];
            sumG += src[srcWidth - 1][GCOMP] * filter[n][GCOMP];
            sumB += src[srcWidth - 1][BCOMP] * filter[n][BCOMP];
            sumA += src[srcWidth - 1][ACOMP] * filter[n][ACOMP];
         }
         else {
            sumR += src[i + n - halfFilterWidth][RCOMP] * filter[n][RCOMP];
            sumG += src[i + n - halfFilterWidth][GCOMP] * filter[n][GCOMP];
            sumB += src[i + n - halfFilterWidth][BCOMP] * filter[n][BCOMP];
            sumA += src[i + n - halfFilterWidth][ACOMP] * filter[n][ACOMP];
         }
      }
      dest[i][RCOMP] = sumR;
      dest[i][GCOMP] = sumG;
      dest[i][BCOMP] = sumB;
      dest[i][ACOMP] = sumA;
   }
}


static void
convolve_2d_reduce(GLint srcWidth, GLint srcHeight,
                   const GLfloat src[][4],
                   GLint filterWidth, GLint filterHeight,
                   const GLfloat filter[][4],
                   GLfloat dest[][4])
{
   GLint dstWidth, dstHeight;
   GLint i, j, n, m;

   if (filterWidth >= 1)
      dstWidth = srcWidth - (filterWidth - 1);
   else
      dstWidth = srcWidth;

   if (filterHeight >= 1)
      dstHeight = srcHeight - (filterHeight - 1);
   else
      dstHeight = srcHeight;

   if (dstWidth <= 0 || dstHeight <= 0)
      return;

   for (j = 0; j < dstHeight; j++) {
      for (i = 0; i < dstWidth; i++) {
         GLfloat sumR = 0.0;
         GLfloat sumG = 0.0;
         GLfloat sumB = 0.0;
         GLfloat sumA = 0.0;
         for (m = 0; m < filterHeight; m++) {
            for (n = 0; n < filterWidth; n++) {
               const GLint k = (j + m) * srcWidth + i + n;
               const GLint f = m * filterWidth + n;
               sumR += src[k][RCOMP] * filter[f][RCOMP];
               sumG += src[k][GCOMP] * filter[f][GCOMP];
               sumB += src[k][BCOMP] * filter[f][BCOMP];
               sumA += src[k][ACOMP] * filter[f][ACOMP];
            }
         }
         dest[j * dstWidth + i][RCOMP] = sumR;
         dest[j * dstWidth + i][GCOMP] = sumG;
         dest[j * dstWidth + i][BCOMP] = sumB;
         dest[j * dstWidth + i][ACOMP] = sumA;
      }
   }
}


static void
convolve_2d_constant(GLint srcWidth, GLint srcHeight,
                     const GLfloat src[][4],