When "Snap to grid" is selected, any time a component is added to or dragged around the diagram, its position will jump to the nearest intersection on the placement grid. When submodel boundaries are dragged, they will jump to the nearest parallel line on the grid. This does not affect link routing, or caption or bowtie positioning.
When "Quick drag" is selected, collision detection is turned off when dragging components and boundaries, and only done at the end of the drag. This allows dragging to be smoother in very complex models on a slow computer.
The keypad in the equation dialogue has a button for inserting a special character (left of AC). By default this is μ, the 'micro-' prefix for physical units. In this box you can set it to any hard-to-find character you use frequently, e.g., π (the numerical constant pi -- copy it from here!). You can also set it to a word.
Influences and other arrows that cross submodel borders are divided into sections. This option controls whether sections of influence arrows can be selected individually. The default is that clicking on a link at any point, or selecting either of its end points, will select all the sections of the link that are part of the same branch. This alternative, of selecting only the section clicked on, allows parts of a link to be deleted, leaving hanging sections that can be rejoined in different combinations. This is useful for separating and rejoining parts of a model, particularly when building a model from a selection of modules which can be connected together in different arrangements.
Flows and squirts can be drawn as either a series of horizontal and vertical sections (following a rectilinear route) or as a straight line (at any angle) between source and sink. Checking or unchecking the 'kink flows' box does not cause the diagram to be redrawn immediately, but when flows are redrawn, they will be redrawn in the new style. The default is for rectilinear flow routing, i.e., kinked if necessary rather than diagonal.
Influences and role arrows are drawn with a default clockwise curvature, but their routes can be adjusted after adding them. The values here set the number of degrees through which they turn when first added -- zero means draw them straight, negative means curve anticlockwise.
Submodels can have a background colour and/or a background image, or neither, in which case the background is transparent. A transparent submodel will show the background of its parent submodel through it. This can look messy if the placement grids do not align, so Simile's default behaviour is to give new submodels their own white background. This opton allows new submodels to be transparent (or black for that retro glow look) by default instead.
In: Contents >> Working with model diagrams >> Preferences