Make "Laplace" an edge filter operation, since it is supposed to be used for edge detection without modifying the alpha channel.
The thing is, for some of the filters, applying them to the alpha channel as well does make sense (e.g. soften/sharpen). Also, the filters are split into two categories, the "normal" ones, and the edge detection ones, which do not modify the alpha. Perhaps I should have done this in the first place, but I think a better fix would be to move the laplace filter to the edge detection group, since it is used just for that. Like so:
diff --git a/source/blender/compositor/nodes/COM_FilterNode.cpp b/source/blender index 7493f24..e8b08ce 100644 --- a/source/blender/compositor/nodes/COM_FilterNode.cpp +++ b/source/blender/compositor/nodes/COM_FilterNode.cpp @@ -49,7 +49,7 @@ void FilterNode::convertToOperations(NodeConverter &converter, operation->set3x3Filter(-1, -1, -1, -1, 9, -1, -1, -1, - break; case CMP_FILT_LAPLACE: - operation = new ConvolutionFilterOperation(); + operation = new ConvolutionEdgeFilterOperation(); operation->set3x3Filter(-1 / 8.0f, -1 / 8.0f, -1 / 8.0f, break; case CMP_FILT_SOBEL: