Earth and rocks are a very important part of complex scenes. They seem very easy, but at the same time it's hard to render them in a believable way. A texture will not do on its own—a proper treatment is necessary. In this big tutorial I'll show you which Adobe Photoshop tools you can use to get natural-looking ground, stones, mountains, desert, and rock ledges.
1. Create a Generic Piece of Ground
When we paint simple scenes, ground is a necessary evil. We know that everyone will ignore it and focus on the main object/character, but if we skip it, it will not go unnoticed. I'll show you the way to create a simple, customizable piece of ground, perfect for a background or a base for something more detailed.
Start with a scene you want to cover with ground. If the objects are on a separate layer, keep the ground under them; if not, draw a base around it and use it as a clipping mask (Control-Alt-G) for all the layers. Fill the base with the basic color for your ground.
Create a New Layer. Fill it with any color, and go to Filter > Noise > Add Noise.
Use the Free Transform Tool (Control-T) to squish the texture.
Use the Free Transform Tool once again. Control-click the corners to drag them separately and to adjust the texture to perspective.
Double click the layer. Go to the Blend If section and play with the sliders in the second row to make the dark areas partially transparent (Alt-click the marker to split it).
Go into Quick Mask Mode (Q). Use the Soft Round brush to select the distant part of the ground.
Exit the mode by pressing Q once again, and invert the selection (Control-Shift-I). Open the Adjustments window (Window > Adjustments) and select Brightness/Contrast. Make Contrast the lowest possible, and Brightness the highest. It will create an aerial perspective.
Find a texture you wan to use for the ground. It shouldn't be too detailed—the more chaotic, the better. I've used dirt. Use the Free Transform Tool to adjust its perspective, just as we did with the noise texture.
If your texture contains elements that shouldn't be overly stretched, don't go right to the horizon—we'll patch it later.
Use the Layer Mask (or just the Eraser Tool) to blend the edge of the texture.
Reset Saturation with Control-U. The color of the texture shouldn't influence the color we have chosen for the ground.
Use the Levels editor (Control-L) to fix the contrast between light and dark elements.
Change the Blend Mode to Overlay.
You can now duplicate (Control-J) the texture and adjust it to the lacking part in the background.
Go into Quick Mask Mode (Q). Select the area illuminated by the light source.
Turn the mask into a selection as before. Increase its Brightness a bit.
Control-click the mask next to the previous adjustment layer to re-create the selection. Add the Color Balance adjustment and shift the color of the illuminated ground to the color of the light source.
The shadows have appeared on their own, but we can stress them even more. Select them with the Quick Mask.
Then use the Brightness/Contrast adjustment to make the shadows darker and less contrasting.
If you want to make the effect stronger, just duplicate the adjustment layer.
Create a New Layer. Double click it to get to its Style.
- Check Color Overlay and select the base color for the stones.
- Check Bevel & Emboss.
- Adjust the Angle to your light source.
- Change the Gloss Contour to something rough.
- Change the color of the Highlight to the color of illuminated ground on your scene.
- The exact values must fit your resolution, so don't copy them from here and instead try to copy the result.
When the style is done, draw stones here and there according to the perspective of your scene. Don't draw them too big!
Duplicate the stones. Right click the layer and Rasterize Layer Style. Then use Control-U to drag the lightness down.
Go to Filter > Blur > Motion Blur to smudge the stones. Use the same Angle as for your light source.
Put the blurred layer under the stones. Grab the Move Tool (V) and use the Arrow keys to place the shadows "behind" the stones.
Merge (Control-E) both layers and blend the stones with the Layer Mask or the Eraser Tool.
If you want to make the shadows more bluish than black, create a New Layer and Fill it with the color of the sky. Then double click it and play with the Blend If sliders to add transparency to the parts over the bright areas.
Then change the Blend Mode to Color and lower the Opacity to your needs.
If you don't like this effect and you have a bit more time to work on it, there's a different method, too. It's especially good if there are distinctive parts, like individual stones, in your texture.
Select these distinctive parts with the Lasso Tool (L). Use Control-Shift-C to copy everything beneath and paste it.
Double click the new layer. With Color Overlay in Overlay mode you can make the surface slightly brighter.
By adding a vertical shadow you can simulate the volume of the stones.
You can add shadow to these stones just as before (motion blur, etc.).
2. Paint a Round Stone
Paint a base shape for your stone.
Find a texture for the stone, like Rock 1. Paste it over the base and clip (Control-Alt-G) the texture.
We need to adjust the shape of the texture to the form of the stone. Go to Filter > Distort > Spherize. Unclip (Control-Alt-G) the texture for a while to see the effect.
Lower the Opacity and use the Free Transform Tool to resize the texture.
Let's shade the stone in a simple way. Create a New Layer and fill it with any color. Double click it and check Gradient Overlay. Use a radial, black and white gradient with white in the center.
Right click the layer and Rasterize Layer Style. Then use the Free Transform Tool to adjust the shading.
Press Control-B to tint the shadow with the color of the environment.
Drag the shading layer below the texture. Double click the texture and play with its Blend If options. The black marker defines the opacity of the texture right above the black areas of the layer beneath. If you move it to the right, the opacity will increase. Alt-click the marker to split it and get a more transitional effect.
Duplicate (Control-J) the shading layer and put it over the texture. Change the Blend Mode to Overlay and play with the Blend If sliders to make dark areas transparent.
Duplicate the texture layer and place it on the top. Right click it and Clear Layer Style. Then use Control-U to reset the Saturation.
Use the Layer Mask or the Eraser Tool to remove this texture almost completely, leaving a subtle area of reflected light in the shadow.
If you want to create a back light effect, create a radial gradient with black in the center and place it like this:
Change its Blend Mode to Screen. Then play with the Blend If sliders to make the light more natural.
3. Paint a Rocky Mountain
Start with a rough outline of the mountain.
Divide the mountain horizontally into big slices.
Add vertical slices.
Lower the Opacity of the sketch and create a New Layer. Using the guide lines below, draw big rock plates.
Repeat the horizontal splitting.
Create a New Layer below the lines and paint a solid base for the mountain. From now on, clip (Control-Alt-G) all new layers to it (including the line art).
Create a New Layer above the lines. Paint the shadows in the crevices.
Paint light in the illuminated areas.
Lower the Opacity of the line art to almost 0. Draw irregular horizontal cracks.
Add irregular vertical cracks.
Shade the cracks.
You can adjust the contrast of the mountain by adding the Levels adjustment layer (Window > Adjustments) and dragging both the outer markers towards the middle.
Find a texture for the surface of your mountain, like Rock 2.
Double click the texture. By changing the Blend If options you'll be able to reveal the crevices without changing the rest of the texture.
Go to Edit > Puppet Warp. Add "pins" all over the mountain.
Then reshape the texture to fit the 3D form of the mountain.
Change the Blend Mode to Hard Light.
If you want to make the near-shadow area textured too, duplicate (Control-J) the texture and change its Blend Mode to Soft Light. Then adjust its Blend If settings to make the light areas transparent.
Finish the mountain by cutting some of the crevices in the edge. You can also adjust Contrast to fit your style.
4. Create a Mountainside
Find a nice, uniform texture, like Rock 3.
Go to Edit > Puppet Warp. This tool is literally made for this sort of transformation! First, "draw" the slopes with the pins.
Drag the pins on the slopes to make the texture bigger and stretched in these areas.
Drag more pins in between the slopes, to make the texture smaller and squeezed in these areas.
Use the Layer Mask or the Eraser Tool to cut the outline of the mountain. It's done! It may take some practice to get a satisfying result, but once you get it, it's an unbelievably fast technique!
Let's shade the slopes. Create a New Layer and clip it (Control-Alt-G) to the texture. Set its Blend Mode to Multiply and paint the shadows—first with light gray, then going darker.
Do the same for the lights, this time using Soft Light for the Blend Mode.
If you want to make the slopes less shiny, double click the light layer and play with the Blend If options.
5. Paint a Mountain Ledge
Create a separate file (from the one you want to paint the ledge in). Draw an ellipse with the Ellipse Tool and modify the shape, or just paint it with a hard brush. This will be the main surface of the ledge.
Go to Edit > Define Brush Preset. Press F5 and change the settings as shown below.
Draw the rock. If the individual "plates" are too far or too close to each other, play with Spacing in Brush Tip Shape in the settings.
Create a New Layer over every part of the ledge and set its Blend Mode to Multiply. Use this layer to paint the shadows.
Merge all the parts and their shadows, and paint over the ledge to make it more natural.
If you feel the contrast is too weak, use the Levels panel (Control-L) to fix it.
If you want to put the focus on the upper side of the ledge, create two New Layers, one in Soft Light mode, and the other in Multiply mode, and paint light and shadow on them.
Find a texture (like Rock 4) and set it to Overlay mode. Use the Free Transform Tool (Control-T) to adjust the perspective to the ledge. Control-drag the corners for this effect.
Use the Layer Mask or the Eraser Tool to cut the redundant parts.
Take the same texture and squish it vertically/stretch horizontally with the Free Transform Tool to get textured lines. Duplicate it (Control-J) to create two copies.
Use Edit > Puppet Warp to add a proper shape to the texture.
Use the Layer Mask or the Eraser Tool to cut the parts outside the ledge.
Do the same with the other part.
6. Paint a Sand Desert
Draw the triangle as below in any way you like. You can create the halves with the Pen Tool (P), or draw it all and color the halves later.
Create a New Layer, clip it (Control-Alt-G), and shade the triangle slightly.
Merge (Control-E) both layers and blend the edge between the halves. You can safely use the Smudge Tool or the Blur Tool for it.
Go to Filter > Noise > Add Noise and add a little grain to the surface of the triangle.
Take the Mixer Brush Tool and set its options as shown below. Resize your brush to fit all the triangle inside, and then hold Alt and press firmly.
Paint a stroke. The effect should be similar to this.
The jagged edge comes from either too much Spacing, or too small a canvas size. However, the smoother the stroke, the harder it is for your computer to handle. A compromise is necessary.
Paint the sand dunes. Pay attention to the direction and the way they overlap.
Use the Free Transform Tool (Control-T) to adjust the perspective. Control-drag the corners to move them individually.
To fix the jagged edges, use your favorite blurring tool on them. I recommend the Mixer Brush Tool in its default mode (Reset Tool to make it go back to the default). The more important the background is, the more attention you should pay to fixing these edges.
Go into Quick Mask Mode (Q) and paint the distant part with the Soft Round brush.
Exit Quick Mask Mode and add the Color Balance adjustment layer to the selection. Make that nearest part warmer in color.
We're Still Not Done!
That's a lot to learn, isn't it? If you liked this tutorial, make sure to check the other ones of the series. And if you want to harness all the elements, stay tuned for the last one—air. It will be more interesting than you may think!