AutoBlend is a tool to automatically calculate the blend masks of projectors or throwers.
If we have several projectors projecting onto the same objects with overlaps, the overlaps would be visible in the projection. That’s why softedge blending is applied and AutoBlend can calculate them for you automatically. So let’s say we have 2 projectors and 3 primitives in the scene from chapter Map your 3D objects to projectors.
To AutoBlend the 2 projectors, you should open the AutoBlend window by either pressing the F2 shortcut or by going to Window -> AutoBlend.
Make sure to select all 3 primitives and click on Blend button. After this, the blend masks should appear on the right.
Please make sure that all the projected objects have render mode set to Unshaded. Otherwise blending might not be perfect.
Modifying the masks manually
Now, where are these blend masks applied? If you double click on one of the projectors, you will open its layout.
On the bottom left part of the layout you can see the AutoBlend node, which outputs the blend mask. This is then connected to Texture Blend node, which blends it with the content itself (the Input node).
You can further adjust the blend masks manually if you want.