renderbuffer.c

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

static void
get_row_alpha8(GLcontext *ctx, struct gl_renderbuffer *arb, GLuint count,
               GLint x, GLint y, void *values)
{
   /* NOTE: 'values' is RGBA format! */
   const GLubyte *src = (const GLubyte *) arb->Data + y * arb->Width + x;
   GLubyte *dst = (GLubyte *) values;
   GLuint i;
   ASSERT(arb != arb->Wrapped);
   ASSERT(arb->DataType == GL_UNSIGNED_BYTE);
   /* first, pass the call to the wrapped RGB buffer */
   arb->Wrapped->GetRow(ctx, arb->Wrapped, count, x, y, values);
   /* second, fill in alpha values from this buffer! */
   for (i = 0; i < count; i++) {
      dst[i * 4 + 3] = src[i];
   }
}


static void
get_values_alpha8(GLcontext *ctx, struct gl_renderbuffer *arb, GLuint count,
                  const GLint x[], const GLint y[], void *values)
{
   GLubyte *dst = (GLubyte *) values;
   GLuint i;
   ASSERT(arb != arb->Wrapped);
   ASSERT(arb->DataType == GL_UNSIGNED_BYTE);
   /* first, pass the call to the wrapped RGB buffer */
   arb->Wrapped->GetValues(ctx, arb->Wrapped, count, x, y, values);
   /* second, fill in alpha values from this buffer! */
   for (i = 0; i < count; i++) {
      const GLubyte *src = (GLubyte *) arb->Data + y[i] * arb->Width + x[i];
      dst[i * 4 + 3] = *src;
   }
}


static void
put_row_alpha8(GLcontext *ctx, struct gl_renderbuffer *arb, GLuint count,
               GLint x, GLint y, const void *values, const GLubyte *mask)
{
   const GLubyte *src = (const GLubyte *) values;
   GLubyte *dst = (GLubyte *) arb->Data + y * arb->Width + x;
   GLuint i;
   ASSERT(arb != arb->Wrapped);
   ASSERT(arb->DataType == GL_UNSIGNED_BYTE);
   /* first, pass the call to the wrapped RGB buffer */
   arb->Wrapped->PutRow(ctx, arb->Wrapped, count, x, y, values, mask);
   /* second, store alpha in our buffer */
   for (i = 0; i < count; i++) {
      if (!mask || mask[i]) {
         dst[i] = src[i * 4 + 3];
      }
   }
}


static void
put_row_rgb_alpha8(GLcontext *ctx, struct gl_renderbuffer *arb, GLuint count,
                   GLint x, GLint y, const void *values, const GLubyte *mask)
{
   const GLubyte *src = (const GLubyte *) values;
   GLubyte *dst = (GLubyte *) arb->Data + y * arb->Width + x;
   GLuint i;
   ASSERT(arb != arb->Wrapped);
   ASSERT(arb->DataType == GL_UNSIGNED_BYTE);
   /* first, pass the call to the wrapped RGB buffer */
   arb->Wrapped->PutRowRGB(ctx, arb->Wrapped, count, x, y, values, mask);
   /* second, store alpha in our buffer */
   for (i = 0; i < count; i++) {
      if (!mask || mask[i]) {
         dst[i] = src[i * 4 + 3];
      }
   }
}


static void
put_mono_row_alpha8(GLcontext *ctx, struct gl_renderbuffer *arb, GLuint count,
                    GLint x, GLint y, const void *value, const GLubyte *mask)
{
   const GLubyte val = ((const GLubyte *) value)[3];
   GLubyte *dst = (GLubyte *) arb->Data + y * arb->Width + x;
   ASSERT(arb != arb->Wrapped);
   ASSERT(arb->DataType == GL_UNSIGNED_BYTE);
   /* first, pass the call to the wrapped RGB buffer */
   arb->Wrapped->PutMonoRow(ctx, arb->Wrapped, count, x, y, value, mask);
   /* second, store alpha in our buffer */
   if (mask) {
      GLuint i;
      for (i = 0; i < count; i++) {
         if (mask[i]) {
            dst[i] = val;
         }
      }
   }
   else {
      _mesa_memset(dst, val, count);
   }
}


static void
put_values_alpha8(GLcontext *ctx, struct gl_renderbuffer *arb, GLuint count,
                  const GLint x[], const GLint y[],
                  const void *values, const GLubyte *mask)
{
   const GLubyte *src = (const GLubyte *) values;
   GLuint i;
   ASSERT(arb != arb->Wrapped);
   ASSERT(arb->DataType == GL_UNSIGNED_BYTE);
   /* first, pass the call to the wrapped RGB buffer */
   arb->Wrapped->PutValues(ctx, arb->Wrapped, count, x, y, values, mask);
   /* second, store alpha in our buffer */
   for (i = 0; i < count; i++) {
      if (!mask || mask[i]) {
         GLubyte *dst = (GLubyte *) arb->Data + y[i] * arb->Width + x[i];
         *dst = src[i * 4 + 3];
      }
   }
}


static void
put_mono_values_alpha8(GLcontext *ctx, struct gl_renderbuffer *arb,
                       GLuint count, const GLint x[], const GLint y[],
                       const void *value, const GLubyte *mask)
{
   const GLubyte val = ((const GLubyte *) value)[3];
   GLuint i;
   ASSERT(arb != arb->Wrapped);
   ASSERT(arb->DataType == GL_UNSIGNED_BYTE);
   /* first, pass the call to the wrapped RGB buffer */
   arb->Wrapped->PutValues(ctx, arb->Wrapped, count, x, y, value, mask);
   /* second, store alpha in our buffer */
   for (i = 0; i < count; i++) {
      if (!mask || mask[i]) {
         GLubyte *dst = (GLubyte *) arb->Data + y[i] * arb->Width + x[i];
         *dst = val;
      }
   }
}


static void
copy_buffer_alpha8(struct gl_renderbuffer* dst, struct gl_renderbuffer* src)
{
   ASSERT(dst->_ActualFormat == GL_ALPHA8);
   ASSERT(src->_ActualFormat == GL_ALPHA8);
   ASSERT(dst->Width == src->Width);
   ASSERT(dst->Height == src->Height);

   _mesa_memcpy(dst->Data, src->Data, dst->Width * dst->Height * sizeof(GLubyte));
}


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


/**
 * Default GetPointer routine.  Always return NULL to indicate that
 * direct buffer access is not supported.
 */
static void *
nop_get_pointer(GLcontext *ctx, struct gl_renderbuffer *rb, GLint x, GLint y)
{
   return NULL;
}


/**
 * Initialize the fields of a gl_renderbuffer to default values.
 */
void
_mesa_init_renderbuffer(struct gl_renderbuffer *rb, GLuint name)
{
   _glthread_INIT_MUTEX(rb->Mutex);

   rb->Magic = RB_MAGIC;
   rb->ClassID = 0;
   rb->Name = name;
   rb->RefCount = 0;
   rb->Delete = _mesa_delete_renderbuffer;

   /* The rest of these should be set later by the caller of this function or
    * the AllocStorage method:
    */
   rb->AllocStorage = NULL;

   rb->Width = 0;
   rb->Height = 0;
   rb->InternalFormat = GL_NONE;
   rb->_ActualFormat = GL_NONE;
   rb->_BaseFormat = GL_NONE;
   rb->DataType = GL_NONE;
   rb->RedBits = rb->GreenBits = rb->BlueBits = rb->AlphaBits = 0;
   rb->IndexBits = 0;
   rb->DepthBits = 0;
   rb->StencilBits = 0;
   rb->Data = NULL;

   /* Point back to ourself so that we don't have to check for Wrapped==NULL
    * all over the drivers.
    */
   rb->Wrapped = rb;

   rb->GetPointer = nop_get_pointer;
   rb->GetRow = NULL;
   rb->GetValues = NULL;
   rb->PutRow = NULL;
   rb->PutRowRGB = NULL;
   rb->PutMonoRow = NULL;
   rb->PutValues = NULL;
   rb->PutMonoValues = NULL;
}


/**
 * Allocate a new gl_renderbuffer object.  This can be used for user-created
 * renderbuffers or window-system renderbuffers.
 */
struct gl_renderbuffer *
_mesa_new_renderbuffer(GLcontext *ctx, GLuint name)
{
   struct gl_renderbuffer *rb = CALLOC_STRUCT(gl_renderbuffer);
   if (rb) {
      _mesa_init_renderbuffer(rb, name);
   }
   return rb;
}


/**
 * Delete a gl_framebuffer.
 * This is the default function for renderbuffer->Delete().
 */
void
_mesa_delete_renderbuffer(struct gl_renderbuffer *rb)
{
   if (rb->Data) {
      _mesa_free(rb->Data);
   }
   _mesa_free(rb);
}


/**
 * Allocate a software-based renderbuffer.  This is called via the
 * ctx->Driver.NewRenderbuffer() function when the user creates a new
 * renderbuffer.
 * This would not be used for hardware-based renderbuffers.
 */
struct gl_renderbuffer *
_mesa_new_soft_renderbuffer(GLcontext *ctx, GLuint name)
{
   struct gl_renderbuffer *rb = _mesa_new_renderbuffer(ctx, name);
   if (rb) {
      rb->AllocStorage = _mesa_soft_renderbuffer_storage;
      /* Normally, one would setup the PutRow, GetRow, etc functions here.
       * But we're doing that in the _mesa_soft_renderbuffer_storage() function
       * instead.
       */
   }
   return rb;
}


/**
 * Add software-based color renderbuffers to the given framebuffer.
 * This is a helper routine for device drivers when creating a
 * window system framebuffer (not a user-created render/framebuffer).
 * Once this function is called, you can basically forget about this
 * renderbuffer; core Mesa will handle all the buffer management and
 * rendering!
 */
GLboolean
_mesa_add_color_renderbuffers(GLcontext *ctx, struct gl_framebuffer *fb,
                              GLuint rgbBits, GLuint alphaBits,
                              GLboolean frontLeft, GLboolean backLeft,
                              GLboolean frontRight, GLboolean backRight)
{
   GLuint b;

   if (rgbBits > 16 || alphaBits > 16) {
      _mesa_problem(ctx,
                    "Unsupported bit depth in _mesa_add_color_renderbuffers");
      return GL_FALSE;
   }

   assert(MAX_COLOR_ATTACHMENTS >= 4);

   for (b = BUFFER_FRONT_LEFT; b <= BUFFER_BACK_RIGHT; b++) {
      struct gl_renderbuffer *rb;

      if (b == BUFFER_FRONT_LEFT && !frontLeft)
         continue;
      else if (b == BUFFER_BACK_LEFT && !backLeft)
         continue;
      else if (b == BUFFER_FRONT_RIGHT && !frontRight)
         continue;
      else if (b == BUFFER_BACK_RIGHT && !backRight)
         continue;

      assert(fb->Attachment[b].Renderbuffer == NULL);

      rb = _mesa_new_renderbuffer(ctx, 0);
      if (!rb) {
         _mesa_error(ctx, GL_OUT_OF_MEMORY, "Allocating color buffer");
         return GL_FALSE;
      }

      if (rgbBits <= 8) {
         if (alphaBits)
            rb->_ActualFormat = GL_RGBA8;
         else
            rb->_ActualFormat = GL_RGB8;
      }
      else {
         assert(rgbBits <= 16);
         if (alphaBits)
            rb->_ActualFormat = GL_RGBA16;
         else
            rb->_ActualFormat = GL_RGBA16; /* don't really have RGB16 yet */
      }
      rb->InternalFormat = rb->_ActualFormat;

      rb->AllocStorage = _mesa_soft_renderbuffer_storage;
      _mesa_add_renderbuffer(fb, b, rb);
   }

   return GL_TRUE;
}


/**
 * Add software-based color index renderbuffers to the given framebuffer.
 * This is a helper routine for device drivers when creating a
 * window system framebuffer (not a user-created render/framebuffer).
 * Once this function is called, you can basically forget about this
 * renderbuffer; core Mesa will handle all the buffer management and
 * rendering!
 */
GLboolean
_mesa_add_color_index_renderbuffers(GLcontext *ctx, struct gl_framebuffer *fb,
                                    GLuint indexBits,
                                    GLboolean frontLeft, GLboolean backLeft,
                                    GLboolean frontRight, GLboolean backRight)
{
   GLuint b;

   if (indexBits > 8) {
      _mesa_problem(ctx,
                "Unsupported bit depth in _mesa_add_color_index_renderbuffers");
      return GL_FALSE;
   }

   assert(MAX_COLOR_ATTACHMENTS >= 4);

   for (b = BUFFER_FRONT_LEFT; b <= BUFFER_BACK_RIGHT; b++) {
      struct gl_renderbuffer *rb;

      if (b == BUFFER_FRONT_LEFT && !frontLeft)
         continue;
      else if (b == BUFFER_BACK_LEFT && !backLeft)
         continue;
      else if (b == BUFFER_FRONT_RIGHT && !frontRight)
         continue;
      else if (b == BUFFER_BACK_RIGHT && !backRight)
         continue;

      assert(fb->Attachment[b].Renderbuffer == NULL);

      rb = _mesa_new_renderbuffer(ctx, 0);
      if (!rb) {
         _mesa_error(ctx, GL_OUT_OF_MEMORY, "Allocating color buffer");
         return GL_FALSE;
      }

      if (indexBits <= 8) {
         /* only support GLuint for now */
         /*rb->InternalFormat = GL_COLOR_INDEX8_EXT;*/
         rb->_ActualFormat = COLOR_INDEX32;
      }
      else {
         rb->_ActualFormat = COLOR_INDEX32;
      }
      rb->InternalFormat = rb->_ActualFormat;

      rb->AllocStorage = _mesa_soft_renderbuffer_storage;
      _mesa_add_renderbuffer(fb, b, rb);
   }

   return GL_TRUE;
}


/**
 * Add software-based alpha renderbuffers to the given framebuffer.
 * This is a helper routine for device drivers when creating a
 * window system framebuffer (not a user-created render/framebuffer).
 * Once this function is called, you can basically forget about this
 * renderbuffer; core Mesa will handle all the buffer management and
 * rendering!
 */
GLboolean
_mesa_add_alpha_renderbuffers(GLcontext *ctx, struct gl_framebuffer *fb,
                              GLuint alphaBits,
                              GLboolean frontLeft, GLboolean backLeft,
                              GLboolean frontRight, GLboolean backRight)
{
   GLuint b;

   /* for window system framebuffers only! */
   assert(fb->Name == 0);

   if (alphaBits > 8) {
      _mesa_problem(ctx,
                    "Unsupported bit depth in _mesa_add_alpha_renderbuffers");
      return GL_FALSE;
   }

   assert(MAX_COLOR_ATTACHMENTS >= 4);

   /* Wrap each of the RGB color buffers with an alpha renderbuffer.
    */
   for (b = BUFFER_FRONT_LEFT; b <= BUFFER_BACK_RIGHT; b++) {
      struct gl_renderbuffer *arb;

      if (b == BUFFER_FRONT_LEFT && !frontLeft)