Defines a pixel grid on the surface of the Earth, via a map projection. If the projection has a standard code, then `crsCode` will be set (non-empty). If the projection is non-standard, then `crsWkt` will be set. If the post-projection transformation is affine, then `affineTransform` will be set.

| JSON representation |
|---|
| ``` { "dimensions": { object (`https://developers.google.com/earth-engine/reference/rest/v1alpha/GridDimensions`) }, "affineTransform": { object (`https://developers.google.com/earth-engine/reference/rest/v1alpha/AffineTransform`) }, // The following is a list of mutually exclusive fields. At most one of the // fields will be set in a response: "crsCode": string, "crsWkt": string // End of mutually exclusive fields. } ``` |

| Fields ||
|---|---|
| `dimensions` | ``object (`https://developers.google.com/earth-engine/reference/rest/v1alpha/GridDimensions`)`` The dimensions of the pixel grid. |
| `affineTransform` | ``object (`https://developers.google.com/earth-engine/reference/rest/v1alpha/AffineTransform`)`` The affine transform. |
| The coordinate reference system of the pixel grid, specified as a standard code where possible, and in WKT format otherwise. The following is a list of mutually exclusive fields. At most one of the fields will be set in a response: ||
| `crsCode` | `string` A standard coordinate reference system code (e.g. "EPSG:4326"). |
| `crsWkt` | `string` A coordinate reference system in WKT format ("Well-Known Text"). |
| End of mutually exclusive fields. ||