Editing Textures with Photoshop

Making Better Raster Textures

01. Overview

In this tutorial, we will show you some common tasks performed with Adobe Photoshop. Photoshop is a powerful and flexible tool that is required for making good looking textures for your models.

02. Making a Tileable Texture

a. Why are Tileable Textures Important?

Textures that do not properly tile will produce ugly seams where the image ends and starts repeating again. Additionally, the human eye detects obvious patterns. A badly tiling texture will display these undesirable patterns as shown in the image below.

A single texture untiled, tiling 2 x 2, and 4 x 4. Look at those ugly seams!

b. Process Breakdown

i. Open your texture in Photoshop. This process works best with textures that are completely square and in multiples of two (so 256 x 256 pixels, 512 x 512, etc.). If your image is not square we suggest that you crop it so it is. You can download the sample texture used in this tutorial by clicking here.

ii. Let’s offset the texture to observe the seam. Select all the pixels in the image with Ctrl-A. Then go to Image -> Crop. It will look like nothing has changed, but what we just did was to make sure that the layer the image is on ends at the extents of the image.

iii. Go to Filter > Other > Offset. In the dialogue box that appears, make sure to select “Wrap Around”.

iv. Use the Spot Healing Brush tool (it looks like a band-aid, below) to paint away seams and undesirable elements. You can also use the “Content-Aware Fill” tool to automatically blend areas together. To access this tool, select the area you want to fill and then go to Edit -> Fill on the menu at the top of the screen. From there, in the “Contents” drop-down menu, select “Content-Aware” and with “Color Adaptation” checked, hit OK.

v. When you’re satisfied with your patching job, run the Offset Filter to check for any remaining seams or undesirable elements. If you did a good job, you’ll have a texture that tiles with no visible seams and less obvious repeating patterns.

03. Removing Lighting from a Texture

A secondary problem with tiling textures is the lighting across the texture can be bright in some areas and dark in others. This becomes very apparent when the tile repeats, so it’s important to even out the lighting using a curves layer and a soft brush.

a. Add Adjustment to the Entire Image

Add a Curves Layer And click the middle of the line and drag to make an arc. This will brighten the whole layer, possibly making the existing bright areas too bright. Don’t worry – we’ll fix this.

b. Invert Your Mask

Click on the white box in your curves layer and Press CRTL+ I to invert the layer. It will turn the mask black, hiding its effects. Black in a mask means that the layer the mask is applied to (in this case, a curves adjustment layer) will be hidden in that spot.

c. Prepare Your Brush

Now create a soft brush. Press B (for “Brush”) to bring up your brush tool. Adjust the brush settings as follows. Opacity: ~20/30% Flow: ~20/30% and Drop your brush hardness to zero.

This creates a soft brush that will be easy to edit your mask with.

d. Paint in Your Mask

Make sure your mask (the black box) in the curves layer is selected and your brush color is set to white.

Then paint in white where the dark area of the texture is. This will allow the curves layer to show through in just the white areas of your mask, brightening just that area of the image. Do this until the density of light is even over the whole image. If you hit X your brush color will switch between foreground and background colors in Photoshop:

If your background color is black then you can easily re-mask areas of your image by switching to the background color and painting over the white in your mask.

When you’re finished your image should be evenly lit, as shown below. Don’t forget that you can go back and adjust the curves layer as well if you need to make the darker area of the image brighter (or lower your brightness adjustment).

e. Video Tutorial – Making Tiling Textures from Photo

This video tutorial explains all of the steps above but goes into a lot more detail about how to turn a photo of a pattern into a tileable texture.

04. Normal Map Generation

a. Why is Normal Map Generation Important?

Normal maps can provide convincing detail to surfaces. Observe the indentations in the image below. Normal maps provide these details without having to model them in.

b. Process Breakdown

i. Open your diffuse texture in Photoshop.

ii. Go to Filter > Generate Normal Map. Photoshop will do a rough calculation of the texture to generate surface information. Adjust the parameters of the normal map with the controls on the right.

iii. That’s all there is to it! Use this image in your model to add extra detail.

05. Hot Keys For Efficient Navigation

Once you have learned where some of these tools live and how to operate them it’s a smart idea to understand how to summon them with the stroke of a key or two. Doing so improves your your speed of navigation around the program and allows for your mental flow to be uninterrupted by UI navigation and be replaced by muscle memory (with a little time and practice).

Below is the list of of our favorites.

  • Create new file: Ctrl-N
  • Create new layer: Ctrl-Shift-N
  • Merge two layers: Select + Ctrl-E
  • Merge all layers: Ctrl-Shift-E
  • Paste in Place: Ctrl-Shift-V
  • Flatten image to new layer: Ctrl + Alt + Shift + E
  • Scale about center of image: Transform -> Alt+Shift on a corner
  • Free transform: Ctrl+T
  • Paste image in same location as copied from (good for patching renders): Ctrl-Shift-V
  • Enter/Exit Selection editor: Q (this will turn your selection a transparent red and you can use the pen and brush tools to edit within this mode that adds and subtracts to the red selection. When you hit Q again anything you have brushed or “penned” in whether an addition or subtraction to the red area will be reflected into your new marquee selection and releases you from edit selection mode. PRO-TIP: CTRL + I will invert your red selection whilst in edit selection mode, as well as marquee selection mode.
  • Change brush size/hardness: Right click while brush is active or use the [ ] keys [ will decrease by an increment of 10 and ] will increase by an increment of 10.
  • Change brush opacity/flow: 0 – 9; two consecutive numbers allows double digit values
  • Rotate Canvas: R
  • Toggle Guides: CTRL + R, this will summon your rulers if you click and drag from this area it will drag over vertical or horizontal lines to create guides for your work.
  • Marquee/Select tool: M
  • Magic Wand tool: W
  • Brush tool: B
  • Paint bucket: G
  • Swap Foreground/Background Colors: X
  • Cycle through tool options: Shift+Tool hotkey (Example: Gradient = Shift+G two times)
  • Increase/decrease brush diameter: alt+right mouse drag left/right
  • Increase/decrease brush softness/hardness: alt+right mouse drag up/down
  • Ctrl-T will enter Free Transform on a layer
  • Holding Ctrl and clicking on a handle in Free Transform will Skew it.
  • Alt-clicking and dragging on a layer mask will allow you to duplicate it to another layer.

06. Increasing Texture Detail

Let’s examine how to improve a low-res imagery. The example below will be using wall art, but you can use these techniques on any image you need to improve.

The original image was 750×500, so first we’ll need to double the resolution. We can do this by opening the image size menu and changing the dimensions.

Make sure to check “Bicubic Smoother (enlargement)”.

Once you have enlarged your map, run it through the Reduce Noise Filter. This can be found under Filter -> Noise -> Reduce Noise.

Play with the noise reduction sliders until you get closer to what you are looking for. My settings are Strength: 6, Preserve Details: 3, Reduce Color Noise: 70, Sharpen Details: 52.

Once you’ve done this, your image should be less noisy but you might have lost some sharpness and detail. We’re going to bring that back by using a High Pass filter. First, duplicate your image layer:

On the second layer, run the “High Pass” filter. This can be found under Filter -> Other -> High Pass.

A value between 0.1 and 5 is usually all that’s needed. Sometimes it’s helpful to make your image black and white before running the filter.

Press “OK” to accept the High Pass filter. Then set the layer with the High Pass filter to “Overlay” in the blend mode settings.

Control the intensity of the sharpening using the opacity controls on the High Pass layer.

You can also use a tool to increase the image detail using a tool called “Live Tracing”, found in Adobe Illustrator.

This image is perfect for Live Tracing because it is made up of bold colors and sharp edges. More intricate or mottled wall art/rugs will usually not benefit from this process.

To begin, launch Illustrator and import the image into the workspace. You can do this by just dragging and dropping it or by going to File -> Open. Once you are in Illustrator, select the “Tracing” workspace on the top right of the Illustrator window.

Select your image in the workspace area. The “Image Trace” options on the right side of your screen will light up.

Select the appropriate pre-set for your image and Illustrator will create a vectorized version of it. Note that changing settings can sometimes take a long time to update the preview – so it might help if you uncheck the “Preview” option. Once you’ve found some settings you like, press the “Trace” button.

Select your vectorized image in Illustrator, then copy (Ctrl-C) and paste (Ctrl-V) it into your upscaled Photoshop image as a new layer. Scale it to the correct resolution, then move it below your source image in the layer stack.

Experiment with blending modes for your Source layer. In this example, Darken works really well to sharpen up the image.