Mapping the Top of a Sphere With GIMP
- 1). Click the "Render" sub-menu of the "Filters" window, then click the "Pattern" item. Click the "Grid" command, then click the up or down arrows of the "Width" slider until the thickness of the gridlines in the preview window matches your needs. The "Grid" filter provides the hash marks that represent a grid map for spheres and other objects.
- 2). Click the up or down arrows of the "Spacing" control until the squares of the grid have reached a size you want, then click "OK" to create the grid.
- 3). Click the "Filter" menu's "Map" sub-menu, then click the "Object" item. This command maps images onto objects like planes and spheres.
- 4). Click the "Sphere" item from the dropdown menu next to the "Map to" label. This tells GIMP you want to wrap the grid image around a sphere rather than around a plane or other object. Click the checkbox labeled "Transparent" if it's checked to turn off the "Transparent" setting. This action will create the sphere on the current background without deleting that background. Click the "New image" checkbox if it's checked. This tells GIMP you want to create the sphere on the current canvas rather than create a new canvas.
- 5). Click "OK" to accept the default value for the remaining parameters and create the image of a sphere mapped with a grid image.
- 6). Click the tool palette icon shaped like a dashed ellipse to run the "Ellipse" selection tool, then drag it around the gridded sphere so that the top portion you want to keep lies within the selection region.
- 7). Click the "Invert" command of the "Select" menu, which selects all image regions besides the one you selected. Press "Delete" to delete those regions and display the top of a mapped sphere.
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