The editing of model grid through 2DH View is mainly done in the Layer Control window. The user first have to click on the pen icon 
to enable modifying, then RMC on the cells to directly edit or RMC on the layer to see additional options.
1. Model Grid Layer: RMC on Model Grid show options to modify the I and J indices of the model such as rotate, flip, transpose (Figure 1). These I-J functions are used during the grid generation- importing process to correct any model I-J orientation issues. Additionally, RMC on the model cell allow us to deactivate that cell or rotate grid cell corners for that cell (Figure 2). This function applies a rotation to the cell rotation angles, it does not rotate the actual cell. If using the CORNERS.INP file, it just applies a user specified rotation to the cell rotation matrix. In EFDC the cell’s rotation matrix is used for velocity plots and interaction with the wind field.
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Figure 3. Triangular cell option in Model Grid layer.
Add New 2. Grid Mask Layer: RMC to add masks add masks (zero-thickness flow barriers) or delete existing masks, as shown in Figure 4.
Anchor Figure 4 Figure 4
Figure 4. Add grid mask.
Add New 3. Grid Connection Layer: Add N-S or E-W grid connectors for different grid domains. Select Grid Connections layer in Layer Control then RMC on a cell from one grid which is to be connected to another grid, and select Add N-S Connection (or Add E-W Connection), then LMC to set the second connection point (see Figure 5).
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