Created attachment 180604 [details] The left, yellow shape is faulty The behavior for draw:path-stretchpoint-x is specified in 19.204 ODF 1.3 (see URL) as "If specified, and if the x/y aspect ratio of the svg:viewBox 19.574 is lower than the x/y aspect ratio of the shape size then the whole path is stretched horizontally at draw:path-stretchpoint-x." The attached document contains a yellow, a blue, a green and a red custom shape. The yellow and green shapes have an attribute draw:path-stretchpoint-x set. The blue and red shape have the same coordinates, but they have no draw:path-stretchpoint-x attribute. The yellow shape has the attributes svg:width="6cm", svg:height="3cm" and svg:viewBox="0 0 21600 10800". So its x/y aspect ratio of the svg:viewBox is 21600/10800=2 and the x/y aspect ratio of its size is 6cm/3cm=2. So the values are equal and therefore there should be no stretching. That means it should look the same as the blue shape. The green shape has the attributes svg:width="6cm", svg:height="6cm" and svg:viewBox="0 0 21600 21600". So its x/y aspect ratio of the svg:viewBox is 21600/21600=1 and the x/y aspect ratio of its size is 6cm/6cm=1. Here it works. The error is in method EnhancedCustomShape2d::SetPathSize() 689 fXRatio = static_cast<double>(aLogicRect.GetWidth()) / static_cast<double>(aLogicRect.GetHeight()); 690 if ( fXRatio > 1 ) 691 fXScale /= fXRatio; 692 else 693 fXRatio = 1.0; Here it tests whether the shape width of the shape is larger than the shape height. But being ODF conform the ratio viewBoxWidht/viewBoxHeight has to be compared to ratio shapeWidth/shapeHeight. Variable aLogicRect has the size of the shape and variables nCoordWidth and nCoordHeight have the size of viewBox. https://opengrok.libreoffice.org/xref/core/svx/source/customshapes/EnhancedCustomShape2d.cxx?r=0a1bfe1e#690
There are more things wrong than the faulty condition, therefore it might be an easyHack, but not with difficultyBeginner.