renderbuffer.c

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

   const GLushort val2 = ((const GLushort *) value)[2];
   const GLushort val3 = ((const GLushort *) value)[3];
   GLushort *dst = (GLushort *) rb->Data + 4 * (y * rb->Width + x);
   ASSERT(rb->DataType == GL_UNSIGNED_SHORT || rb->DataType == GL_SHORT);
   if (!mask && val0 == 0 && val1 == 0 && val2 == 0 && val3 == 0) {
      /* common case for clearing accum buffer */
      _mesa_bzero(dst, count * 4 * sizeof(GLushort));
   }
   else {
      GLuint i;
      for (i = 0; i < count; i++) {
         if (!mask || mask[i]) {
            dst[i * 4 + 0] = val0;
            dst[i * 4 + 1] = val1;
            dst[i * 4 + 2] = val2;
            dst[i * 4 + 3] = val3;
         }
      }
   }
}


static void
put_values_ushort4(GLcontext *ctx, struct gl_renderbuffer *rb, GLuint count,
                   const GLint x[], const GLint y[], const void *values,
                   const GLubyte *mask)
{
   const GLushort *src = (const GLushort *) values;
   GLuint i;
   ASSERT(rb->DataType == GL_UNSIGNED_SHORT || rb->DataType == GL_SHORT);
   for (i = 0; i < count; i++) {
      if (!mask || mask[i]) {
         GLushort *dst = (GLushort *) rb->Data + 4 * (y[i] * rb->Width + x[i]);
         dst[0] = src[i * 4 + 0];
         dst[1] = src[i * 4 + 1];
         dst[2] = src[i * 4 + 2];
         dst[3] = src[i * 4 + 3];
      }
   }
}


static void
put_mono_values_ushort4(GLcontext *ctx, struct gl_renderbuffer *rb,
                        GLuint count, const GLint x[], const GLint y[],
                        const void *value, const GLubyte *mask)
{
   const GLushort val0 = ((const GLushort *) value)[0];
   const GLushort val1 = ((const GLushort *) value)[1];
   const GLushort val2 = ((const GLushort *) value)[2];
   const GLushort val3 = ((const GLushort *) value)[3];
   GLuint i;
   ASSERT(rb->DataType == GL_UNSIGNED_SHORT || rb->DataType == GL_SHORT);
   for (i = 0; i < count; i++) {
      if (!mask || mask[i]) {
         GLushort *dst = (GLushort *) rb->Data + 4 * (y[i] * rb->Width + x[i]);
         dst[0] = val0;
         dst[1] = val1;
         dst[2] = val2;
         dst[3] = val3;
      }
   }
}



/**
 * This is a software fallback for the gl_renderbuffer->AllocStorage
 * function.
 * Device drivers will typically override this function for the buffers
 * which it manages (typically color buffers, Z and stencil).
 * Other buffers (like software accumulation and aux buffers) which the driver
 * doesn't manage can be handled with this function.
 *
 * This one multi-purpose function can allocate stencil, depth, accum, color
 * or color-index buffers!
 *
 * This function also plugs in the appropriate GetPointer, Get/PutRow and
 * Get/PutValues functions.
 */
GLboolean
_mesa_soft_renderbuffer_storage(GLcontext *ctx, struct gl_renderbuffer *rb,
                                GLenum internalFormat,
                                GLuint width, GLuint height)
{
   GLuint pixelSize;

   /* first clear these fields */
   rb->RedBits =
   rb->GreenBits =
   rb->BlueBits =
   rb->AlphaBits =
   rb->IndexBits =
   rb->DepthBits =
   rb->StencilBits = 0;

   switch (internalFormat) {
   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:
      rb->_ActualFormat = GL_RGB8;
      rb->_BaseFormat = GL_RGB;
      rb->DataType = GL_UNSIGNED_BYTE;
      rb->GetPointer = get_pointer_ubyte3;
      rb->GetRow = get_row_ubyte3;
      rb->GetValues = get_values_ubyte3;
      rb->PutRow = put_row_ubyte3;
      rb->PutRowRGB = put_row_rgb_ubyte3;
      rb->PutMonoRow = put_mono_row_ubyte3;
      rb->PutValues = put_values_ubyte3;
      rb->PutMonoValues = put_mono_values_ubyte3;
      rb->RedBits   = 8 * sizeof(GLubyte);
      rb->GreenBits = 8 * sizeof(GLubyte);
      rb->BlueBits  = 8 * sizeof(GLubyte);
      rb->AlphaBits = 0;
      pixelSize = 3 * sizeof(GLubyte);
      break;
   case GL_RGBA:
   case GL_RGBA2:
   case GL_RGBA4:
   case GL_RGB5_A1:
   case GL_RGBA8:
      rb->_ActualFormat = GL_RGBA8;
      rb->_BaseFormat = GL_RGBA;
      rb->DataType = GL_UNSIGNED_BYTE;
      rb->GetPointer = get_pointer_ubyte4;
      rb->GetRow = get_row_ubyte4;
      rb->GetValues = get_values_ubyte4;
      rb->PutRow = put_row_ubyte4;
      rb->PutRowRGB = put_row_rgb_ubyte4;
      rb->PutMonoRow = put_mono_row_ubyte4;
      rb->PutValues = put_values_ubyte4;
      rb->PutMonoValues = put_mono_values_ubyte4;
      rb->RedBits   = 8 * sizeof(GLubyte);
      rb->GreenBits = 8 * sizeof(GLubyte);
      rb->BlueBits  = 8 * sizeof(GLubyte);
      rb->AlphaBits = 8 * sizeof(GLubyte);
      pixelSize = 4 * sizeof(GLubyte);
      break;
   case GL_RGB10_A2:
   case GL_RGBA12:
   case GL_RGBA16:
      rb->_ActualFormat = GL_RGBA16;
      rb->_BaseFormat = GL_RGBA;
      rb->DataType = GL_UNSIGNED_SHORT;
      rb->GetPointer = get_pointer_ushort4;
      rb->GetRow = get_row_ushort4;
      rb->GetValues = get_values_ushort4;
      rb->PutRow = put_row_ushort4;
      rb->PutRowRGB = put_row_rgb_ushort4;
      rb->PutMonoRow = put_mono_row_ushort4;
      rb->PutValues = put_values_ushort4;
      rb->PutMonoValues = put_mono_values_ushort4;
      rb->RedBits   = 8 * sizeof(GLushort);
      rb->GreenBits = 8 * sizeof(GLushort);
      rb->BlueBits  = 8 * sizeof(GLushort);
      rb->AlphaBits = 8 * sizeof(GLushort);
      pixelSize = 4 * sizeof(GLushort);
      break;
#if 00
   case GL_ALPHA8:
      rb->_ActualFormat = GL_ALPHA8;
      rb->_BaseFormat = GL_RGBA; /* Yes, not GL_ALPHA! */
      rb->DataType = GL_UNSIGNED_BYTE;
      rb->GetPointer = get_pointer_alpha8;
      rb->GetRow = get_row_alpha8;
      rb->GetValues = get_values_alpha8;
      rb->PutRow = put_row_alpha8;
      rb->PutRowRGB = NULL;
      rb->PutMonoRow = put_mono_row_alpha8;
      rb->PutValues = put_values_alpha8;
      rb->PutMonoValues = put_mono_values_alpha8;
      rb->RedBits   = 0; /*red*/
      rb->GreenBits = 0; /*green*/
      rb->BlueBits  = 0; /*blue*/
      rb->AlphaBits = 8 * sizeof(GLubyte);
      pixelSize = sizeof(GLubyte);
      break;
#endif
   case GL_STENCIL_INDEX:
   case GL_STENCIL_INDEX1_EXT:
   case GL_STENCIL_INDEX4_EXT:
   case GL_STENCIL_INDEX8_EXT:
      rb->_ActualFormat = GL_STENCIL_INDEX8_EXT;
      rb->_BaseFormat = GL_STENCIL_INDEX;
      rb->DataType = GL_UNSIGNED_BYTE;
      rb->GetPointer = get_pointer_ubyte;
      rb->GetRow = get_row_ubyte;
      rb->GetValues = get_values_ubyte;
      rb->PutRow = put_row_ubyte;
      rb->PutRowRGB = NULL;
      rb->PutMonoRow = put_mono_row_ubyte;
      rb->PutValues = put_values_ubyte;
      rb->PutMonoValues = put_mono_values_ubyte;
      rb->StencilBits = 8 * sizeof(GLubyte);
      pixelSize = sizeof(GLubyte);
      break;
   case GL_STENCIL_INDEX16_EXT:
      rb->_ActualFormat = GL_STENCIL_INDEX16_EXT;
      rb->_BaseFormat = GL_STENCIL_INDEX;
      rb->DataType = GL_UNSIGNED_SHORT;
      rb->GetPointer = get_pointer_ushort;
      rb->GetRow = get_row_ushort;
      rb->GetValues = get_values_ushort;
      rb->PutRow = put_row_ushort;
      rb->PutRowRGB = NULL;
      rb->PutMonoRow = put_mono_row_ushort;
      rb->PutValues = put_values_ushort;
      rb->PutMonoValues = put_mono_values_ushort;
      rb->StencilBits = 8 * sizeof(GLushort);
      pixelSize = sizeof(GLushort);
      break;
   case GL_DEPTH_COMPONENT:
   case GL_DEPTH_COMPONENT16:
      rb->_ActualFormat = GL_DEPTH_COMPONENT16;
      rb->_BaseFormat = GL_DEPTH_COMPONENT;
      rb->DataType = GL_UNSIGNED_SHORT;
      rb->GetPointer = get_pointer_ushort;
      rb->GetRow = get_row_ushort;
      rb->GetValues = get_values_ushort;
      rb->PutRow = put_row_ushort;
      rb->PutRowRGB = NULL;
      rb->PutMonoRow = put_mono_row_ushort;
      rb->PutValues = put_values_ushort;
      rb->PutMonoValues = put_mono_values_ushort;
      rb->DepthBits = 8 * sizeof(GLushort);
      pixelSize = sizeof(GLushort);
      break;
   case GL_DEPTH_COMPONENT24:
   case GL_DEPTH_COMPONENT32:
      rb->_BaseFormat = GL_DEPTH_COMPONENT;
      rb->DataType = GL_UNSIGNED_INT;
      rb->GetPointer = get_pointer_uint;
      rb->GetRow = get_row_uint;
      rb->GetValues = get_values_uint;
      rb->PutRow = put_row_uint;
      rb->PutRowRGB = NULL;
      rb->PutMonoRow = put_mono_row_uint;
      rb->PutValues = put_values_uint;
      rb->PutMonoValues = put_mono_values_uint;
      if (internalFormat == GL_DEPTH_COMPONENT24) {
         rb->_ActualFormat = GL_DEPTH_COMPONENT24;
         rb->DepthBits = 24;
      }
      else {
         rb->_ActualFormat = GL_DEPTH_COMPONENT32;
         rb->DepthBits = 32;
      }
      pixelSize = sizeof(GLuint);
      break;
   case GL_DEPTH_STENCIL_EXT:
   case GL_DEPTH24_STENCIL8_EXT:
      rb->_ActualFormat = GL_DEPTH24_STENCIL8_EXT;
      rb->_BaseFormat = GL_DEPTH_STENCIL_EXT;
      rb->DataType = GL_UNSIGNED_INT_24_8_EXT;
      rb->GetPointer = get_pointer_uint;
      rb->GetRow = get_row_uint;
      rb->GetValues = get_values_uint;
      rb->PutRow = put_row_uint;
      rb->PutRowRGB = NULL;
      rb->PutMonoRow = put_mono_row_uint;
      rb->PutValues = put_values_uint;
      rb->PutMonoValues = put_mono_values_uint;
      rb->DepthBits = 24;
      rb->StencilBits = 8;
      pixelSize = sizeof(GLuint);
      break;
   case GL_COLOR_INDEX8_EXT:
      rb->_ActualFormat = GL_COLOR_INDEX8_EXT;
      rb->_BaseFormat = GL_COLOR_INDEX;
      rb->DataType = GL_UNSIGNED_BYTE;
      rb->GetPointer = get_pointer_ubyte;
      rb->GetRow = get_row_ubyte;
      rb->GetValues = get_values_ubyte;
      rb->PutRow = put_row_ubyte;
      rb->PutRowRGB = NULL;
      rb->PutMonoRow = put_mono_row_ubyte;
      rb->PutValues = put_values_ubyte;
      rb->PutMonoValues = put_mono_values_ubyte;
      rb->IndexBits = 8 * sizeof(GLubyte);
      pixelSize = sizeof(GLubyte);
      break;
   case GL_COLOR_INDEX16_EXT:
      rb->_ActualFormat = GL_COLOR_INDEX16_EXT;
      rb->_BaseFormat = GL_COLOR_INDEX;
      rb->DataType = GL_UNSIGNED_SHORT;
      rb->GetPointer = get_pointer_ushort;
      rb->GetRow = get_row_ushort;
      rb->GetValues = get_values_ushort;
      rb->PutRow = put_row_ushort;
      rb->PutRowRGB = NULL;
      rb->PutMonoRow = put_mono_row_ushort;
      rb->PutValues = put_values_ushort;
      rb->PutMonoValues = put_mono_values_ushort;
      rb->IndexBits = 8 * sizeof(GLushort);
      pixelSize = sizeof(GLushort);
      break;
   case COLOR_INDEX32:
      rb->_ActualFormat = COLOR_INDEX32;
      rb->_BaseFormat = GL_COLOR_INDEX;
      rb->DataType = GL_UNSIGNED_INT;
      rb->GetPointer = get_pointer_uint;
      rb->GetRow = get_row_uint;
      rb->GetValues = get_values_uint;
      rb->PutRow = put_row_uint;
      rb->PutRowRGB = NULL;
      rb->PutMonoRow = put_mono_row_uint;
      rb->PutValues = put_values_uint;
      rb->PutMonoValues = put_mono_values_uint;
      rb->IndexBits = 8 * sizeof(GLuint);
      pixelSize = sizeof(GLuint);
      break;
   default:
      _mesa_problem(ctx, "Bad internalFormat in _mesa_soft_renderbuffer_storage");
      return GL_FALSE;
   }

   ASSERT(rb->DataType);
   ASSERT(rb->GetPointer);
   ASSERT(rb->GetRow);
   ASSERT(rb->GetValues);
   ASSERT(rb->PutRow);
   ASSERT(rb->PutMonoRow);
   ASSERT(rb->PutValues);
   ASSERT(rb->PutMonoValues);

   /* free old buffer storage */
   if (rb->Data) {
      _mesa_free(rb->Data);
      rb->Data = NULL;
   }

   if (width > 0 && height > 0) {
      /* allocate new buffer storage */
      rb->Data = _mesa_malloc(width * height * pixelSize);
      if (rb->Data == NULL) {
         rb->Width = 0;
         rb->Height = 0;
         _mesa_error(ctx, GL_OUT_OF_MEMORY,
                     "software renderbuffer allocation (%d x %d x %d)",
                     width, height, pixelSize);
         return GL_FALSE;
      }
   }

   rb->Width = width;
   rb->Height = height;

   return GL_TRUE;
}



/**********************************************************************/
/**********************************************************************/
/**********************************************************************/


/**
 * Here we utilize the gl_renderbuffer->Wrapper field to put an alpha
 * buffer wrapper around an existing RGB renderbuffer (hw or sw).
 *
 * When PutRow is called (for example), we store the alpha values in
 * this buffer, then pass on the PutRow call to the wrapped RGB
 * buffer.
 */


static GLboolean
alloc_storage_alpha8(GLcontext *ctx, struct gl_renderbuffer *arb,
                     GLenum internalFormat, GLuint width, GLuint height)
{
   ASSERT(arb != arb->Wrapped);
   ASSERT(arb->_ActualFormat == GL_ALPHA8);

   /* first, pass the call to the wrapped RGB buffer */
   if (!arb->Wrapped->AllocStorage(ctx, arb->Wrapped, internalFormat,
                                  width, height)) {
      return GL_FALSE;
   }

   /* next, resize my alpha buffer */
   if (arb->Data) {
      _mesa_free(arb->Data);
   }

   arb->Data = _mesa_malloc(width * height * sizeof(GLubyte));
   if (arb->Data == NULL) {
      arb->Width = 0;
      arb->Height = 0;
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "software alpha buffer allocation");
      return GL_FALSE;
   }

   arb->Width = width;
   arb->Height = height;

   return GL_TRUE;
}


/**
 * Delete an alpha_renderbuffer object, as well as the wrapped RGB buffer.
 */
static void
delete_renderbuffer_alpha8(struct gl_renderbuffer *arb)
{
   if (arb->Data) {
      _mesa_free(arb->Data);
   }
   ASSERT(arb->Wrapped);
   ASSERT(arb != arb->Wrapped);
   arb->Wrapped->Delete(arb->Wrapped);
   arb->Wrapped = NULL;
   _mesa_free(arb);
}


static void *
get_pointer_alpha8(GLcontext *ctx, struct gl_renderbuffer *arb,
                   GLint x, GLint y)
{
   return NULL;   /* don't allow direct access! */
}