How to make a sunray in Gimp

You can use your blocky gradient to make a super quick sunray effect.

Prepare a 24 Bar Gradient.

Set up your canvas (im using 700x700px) with guides at 50% horizontal and vertical.

 Activate the 'Gradient Tool' and for the Options', tick 'Adaptive Supersampling' to get the best quality.

For the shape choose Conical and asymetric.

Now drag the mousepointer from the crossing of the guides to the edge of the canvas. You can either restrain angle by holding down Ctrl or use the snap to canvas edges option.

Bam, instant sunray !

In case you wondered what happens when you choose the symetric cone shape: your sunray will come out wrong….

...and this is what happens when you dont use 'Adaptive Supersampling'. Jaggy Edges......

For different colours, here is a quick way of changing the colours and keep it flexible.

Copy the b/w sunray layer to the clipboard.

Create two new layers in your colours of choice.

Add a layermask to the top layer.

With the layermask selected, paste.

A floating layer will appear and you must click the little anchor to merge it down.

Now you can change the colour easily by dragging and dropping colours.
This way, you will never need more than one black & white gradient and still have every colour you want.

But theres more !

Create a 12 Bars sunray.

Put a new layer on top and draw an 8 Bar gradient with the shape set to 'Radial'.

Now change the Blend Mode to ' Difference' and you get a checkerboard Star Wars style.

We can colourise it the same way we did with the sunray.

Go to Edit → Copy Visible.

Create two new layers in the colours you want.

Add a layermask to top layer.

With the layermask selected, paste and anchor.