Wednesday, 3 January 2018

How to make a blocky gradient

Gimp's Gradient Editor can be intimidating. Im here to change that.

In this tutorial i will show you how to make a blocky gradient that has lots of uses.

Make sure your colours go from black to white.

Click 'Create New Gradient' at the bottom of the Gradient Tab.
A window will pop up. You can resize this window to make it larger.
Give the gradient a name ('8 Bar') and save it.

Go inside the right-click menu and 'Replicate Segment' by 2.

Select only the left part of the gradient by clicking inside the bar where the little triangles are located.
Change the colour of the segment to black by changing the 'Right Endpoint's Colour'.

Next select the right segment and change it to white.

Now select both segments by holding Shift and replicate again. We want eight bars, so we have to replicate by four times.

And thats the whole procedure. You can exit the gradient editor - it automatically saves.

You should make yourself an arsenal of blocky gradients: 8, 10, 12, 24 and 32 bars are good for a start !
I will show you two uses in the next tutorial.

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.

Tuesday, 2 January 2018

How to make a dynamic colour gradient

Using layermasks to apply colours is a very universal and elegant technique, but if you want the ultimate way of making a quick sunray, here's how you do it:

instead of limiting our custom gradient to black & white, we set it up with dynamic colours right from the start.
Follow all the steps described in the Blocky Gradient Tutorial, but when you apply the colours, use the 'Colour Type' option.

Do this for the left and right colours of both segments !

Now the gradient will pick up the colours of the active Fore- and Backgroundcolours you have chosen in the Main Toolbox.