ID 253491 - Displaced geometry sometimes causes paint to become tessellated

Problem summary
When using a displacement layer inside of a shader, paint can sometimes become tessellated and misplaced.

Customer reported version
Multiple
Customer reported platform
Mac OSx Specific
Steps to reproduce

1) Launch Mari

2) Open the sample head project

3) Click on the Shaders tab at the right of the UI

4) In the second scrollable section of the Shaders panel, scroll down to the Bump dropdown and click on "Bump_Head_Geo" and set it to the blank portion at the top of the dropdown list

5) Scroll down to the Displacement section and select the blank portion and set it to "Bump_Head_Geo"

6) Scroll down futher to the Displacement Scale slider and set it to 0.04

7) Move the cursor over the viewport and paint on the model

8) Hit the option key to bake the paint onto the model and wait for the bake operation to complete

Note: This operation is extremely heavy on your machine so can, on occasion, crash before completion.

Workaround
Try not to paint with displacement active. Painting whilst viewing the 'current channel' instead of the BRDF shader also works.

Reproduced by support
Mari 3.1v3 - iMac 10.12 w/ ATI Radeon HD
Mari 3.1v3 - Macbook Pro 10.10.5 w/ Geforce GT 750M 2048 MB
Mari 3.2v1 - iMac 10.12 w/ ATI Radeon HD 
Mari 3.2v1 - MacPro 10.12 w/ AMD FirePro D500

Not Reproducible 
Mari 3.1v3 - Windows 7 (seems to be OSx specific)
Mari 3.1v3 - MacPro 10.12 w/ AMD FirePro D700


Expected behaviour
The painted stroke should appear the same both before and after baking.

Actual behaviour
Paint is miscalculated, displaced and sometimes creates artefacts. Results varied between tested machines.

Macbook Pro: