Sample OPJ to download to try: isometic layer.opj
(ORG-2681)
For 2D Graphs, it's on Size/Speed tab of Layer level of Plot Details dialog. When this option is selected, Graph layers can be set to isometric scaling, which will result in the X and Y axes will be being forced to have the same length in pixel for pixels, for the same scale increment. When the layer is resized, the aspect ratio will be locked/maintained. Thus for example, if X axis spans from 0 to 10 and y axis spans from 0 to 5, isometric scaling will result in a layer with height precisely equal to one-half of the width.
For 2D Graphs, the control can be found in the Size/Speed tab at the Layer level of Plot Details dialog.The check box will be hidden when the scale is not linear.
For 3D graphs, it's on the control is on the Axis tab of at the Layer level in of Plot Details dialog.