Image Subrect Editor

The Image Subrect Editor window

Image Subrect Editor is a tool in Source 2 used for making Hotspots. Hotspots are predefined sections of a texture used to apply materials to Hammer geometry fast and easy.

Note: Image Subrect Editor is not included in SteamVR Home.

Todo: Figure out what should and shouldn't be on this page. Should the Half-Life: Alyx Workshop Tools/Level Design/Hotspot Texturing be reformatted to be hotspot applying only?

Todo: Should the rect file in the material editor be mentioned here? Should this just be the hotspot page, even though it'd then make it pertain to hammer, mat, and ISE?

1. Viewport

The viewport is where rectangles are drawn to specify what parts of the texture can get applied to hammer geometry.

• In Create mode, click dragging in the viewport will draw a rectangle.
• In Adjust mode, click dragging on an existing rectangle will move it. You can also move edges and corners.
• Clicking an existing rectangle will select that rectangle, allowing you to change it's properties. You can hold ⇧ Shift to select multiple rectangles and hold Ctrl to deselect rectangles.
• The grid size can be changed with [ to make it smaller and ] to make it bigger. These options are also under "Edit." Grid visibility can also be toggled here.
• Holding Alt will let you adjust the rectangles as you were in Adjust mode.

Note:You can only select existing rectangles in Create mode.

Note:Adjusting an existing rectangle will reset that rectangles properties. (If it's marked as "Allow Rotation" or "Allow Tiling.")

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  Drawing rectangles in the Subrect Editor (Click to See Gif!)

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  Adjusting rectangles in the Subrect Editor (Click to See Gif!)

2. Rectangle Properties

This is where you draw the squares that make up where UV. There are two modes: Create and Adjust.

• Create will allow you to draw new rectangles across the texture.
• Adjust lets you change the size of previously drawn rectangles.

There are two options available to change on selected rectangles.

• "Allow Rotation" allows that rectangle to be rotated when applying the hotspot in Hammer.
• "Allow Tiling" (not in ) will tile that rectangle when applied to faces in hammer.

Note:  When you check "Allow Tiling" on a rectangle, that rectangle will tile horizontally, never vertically.

Note:  Checking "Allow Tiling" on a rectangle that isn't the width of the texture will still tile the whole width, not the rectangle. Basic UV rules still apply.

"Inset X/Y" fields will make the that rectangle smaller without needing to change grid size. This is useful for fine tuning.

Rectangle Properties Section

3. Active Material

You can choose a material to reference in the viewport. This is useful for creating rectangles for a trimsheet.
When a material is selected, you can then change the preview to any texture the currently selected material uses.

Image Subrect Editor with Preview Texture

TODO

Create section specifying use in Material Editor and Hammer