Here's a bounding box, in two dimensions. The blue dot is the entity's origin. The red dot is the entity's "max size." The green dot is the entity's "minimum size."
Since horizontally there are 24 pixels between the origin and the max size position, and vertically there are 48 pixels between the origin and the max size position, the max size (second parameter of EngFunc_SetSize) would be {24.0,48.0}.
Similarly, since horizontally there are 24 pixels between the origin and the min size position, and vertically there are 48 pixels between the origin and the min size position,
but in the opposite direction, the min size (first parameter of EngFunc_SetSize) would be {
-24.0,
-48.0}.
Essentially, the mins and maxs are the distances from the origin of the entity to the two extreme corners of the bounding box of the entity. Note that in Half-Life, these are in 3D.
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