+ /* Update completeness status of readFb and drawFb. */
+ _mesa_update_framebuffer(ctx, readFb, drawFb);
+
+ /* Make sure drawFb has an initialized bounding box. */
+ _mesa_update_draw_buffer_bounds(ctx, drawFb);
+
+ if (!no_error) {
+ const GLbitfield legalMaskBits = (GL_COLOR_BUFFER_BIT |
+ GL_DEPTH_BUFFER_BIT |
+ GL_STENCIL_BUFFER_BIT);
+
+ /* check for complete framebuffers */
+ if (drawFb->_Status != GL_FRAMEBUFFER_COMPLETE_EXT ||
+ readFb->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
+ _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
+ "%s(incomplete draw/read buffers)", func);
+ return;
+ }
+
+ if (!is_valid_blit_filter(ctx, filter)) {
+ _mesa_error(ctx, GL_INVALID_ENUM, "%s(invalid filter %s)", func,
+ _mesa_enum_to_string(filter));
+ return;
+ }
+
+ if ((filter == GL_SCALED_RESOLVE_FASTEST_EXT ||
+ filter == GL_SCALED_RESOLVE_NICEST_EXT) &&
+ (readFb->Visual.samples == 0 || drawFb->Visual.samples > 0)) {
+ _mesa_error(ctx, GL_INVALID_OPERATION, "%s(%s: invalid samples)", func,
+ _mesa_enum_to_string(filter));
+ return;
+ }
+
+ if (mask & ~legalMaskBits) {
+ _mesa_error(ctx, GL_INVALID_VALUE, "%s(invalid mask bits set)", func);
+ return;
+ }
+
+ /* depth/stencil must be blitted with nearest filtering */
+ if ((mask & (GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT))
+ && filter != GL_NEAREST) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "%s(depth/stencil requires GL_NEAREST filter)", func);
+ return;
+ }
+
+ if (_mesa_is_gles3(ctx)) {
+ /* Page 194 (page 206 of the PDF) in section 4.3.2 of the OpenGL ES
+ * 3.0.1 spec says:
+ *
+ * "If SAMPLE_BUFFERS for the draw framebuffer is greater than
+ * zero, an INVALID_OPERATION error is generated."
+ */
+ if (drawFb->Visual.samples > 0) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "%s(destination samples must be 0)", func);
+ return;
+ }
+
+ /* Page 194 (page 206 of the PDF) in section 4.3.2 of the OpenGL ES
+ * 3.0.1 spec says:
+ *
+ * "If SAMPLE_BUFFERS for the read framebuffer is greater than
+ * zero, no copy is performed and an INVALID_OPERATION error is
+ * generated if the formats of the read and draw framebuffers are
+ * not identical or if the source and destination rectangles are
+ * not defined with the same (X0, Y0) and (X1, Y1) bounds."
+ *
+ * The format check was made above because desktop OpenGL has the same
+ * requirement.
+ */
+ if (readFb->Visual.samples > 0
+ && (srcX0 != dstX0 || srcY0 != dstY0
+ || srcX1 != dstX1 || srcY1 != dstY1)) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "%s(bad src/dst multisample region)", func);
+ return;
+ }
+ } else {
+ if (readFb->Visual.samples > 0 &&
+ drawFb->Visual.samples > 0 &&
+ readFb->Visual.samples != drawFb->Visual.samples) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "%s(mismatched samples)", func);
+ return;
+ }
+
+ /* extra checks for multisample copies... */
+ if ((readFb->Visual.samples > 0 || drawFb->Visual.samples > 0) &&
+ (filter == GL_NEAREST || filter == GL_LINEAR)) {
+ /* src and dest region sizes must be the same */
+ if (abs(srcX1 - srcX0) != abs(dstX1 - dstX0) ||
+ abs(srcY1 - srcY0) != abs(dstY1 - dstY0)) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "%s(bad src/dst multisample region sizes)", func);
+ return;
+ }
+ }
+ }
+ }
+