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This tutorial introduces the mechanics of zooming textures in order to change the size of their features as well as make them repeat more or less often.
In the Overview tab, start a new document and select the "Legacy Presets/Stone/Muted" preset category, then click the "Porous Rock" preset texture (you'll probably need to scroll down to find the preset).
As don't for previous tutorials, switch to the Nodes tab, and enter the Group. The texture's construction is revealed: a Substance Lab, which feeds into a Weather Lab, which in turn feeds into a Sharpen node.
Let's see what the texture looks like when tiled. Set the render resolution to 150 x 150, then click the Render Texture button. (Render resolution can be set using the numeric field in the main the main button bar.)
The rendered result is shown above. One of the texture's features has been circled in red to show how often it repeats. In a rendered scene where the viewpoint is fairly close to the texture, these repetitions are unlikely to be noticeable. However, as the viewpoint moves farther away from the texture causing a greater number of repetitions to fit in the scene, the repetitions will become increasingly noticeable as a grid-like pattern forms. Fortunately, with Genetica's zoom functionality this problem is easily solved by making a texture repeat less often.
Click the Nodes tab to switch back to the main workspace. Right-click the Sharpen node (the one at the very bottom), and in the popup menu select Zoom Out Branch > 2X. Next, set the render resolution to 300 x 300, then click the Render Texture button.
The left part of the above illustration shows the texture that was rendered in Step 1, while the right portion shows the result of the current step. As you can see the texture now covers four times as much surface area without repeating. This means that in your final scene the viewpoint can be twice the distance from a surface using our new texture before repetitions become noticeable.
The Zoom functions affect an entire branch, in other words, the current node plus all of its children. The reason the entire texture was zoomed in the previous step was because we right-clicked the very last node of the texture, which with its children encompassed the entire texture.
Zoom functions can also be used on individual sub-branches in order to change the relative sizes/frequencies of a texture's various elements. Inspecting the texture more closely we can see that it has two main elements, 1) tiny holes throughout its surface and 2) larger, lighter-colored mounds that give the surface a bubbly appearance. In this step we will increase the size of the holes without affecting the size and placement of the mounds.
If you haven't already switched back to the main workspace, click the Nodes tab. Now right-click the Substance Lab (the one at the very top), and select Zoom In Branch > 2X. (Note that this time we clicked Zoom In Branch, not Zoom Out Branch like last time.)
The above image shows the texture before and after our most recent Zoom In operation. As you can see, the holes have been zoomed in while the mounds have preserved their size.
Next: The Using Effect Maps tutorial shows you how to generate various effect maps, such as bump and specular maps, for use in your external 3D application.
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