Melon's Rounded Boxes

A way of rounding polygons with proper UV mapping

Installation

1. Download the file
2. Put it in your project
3. Modify the file to declare the local as global or use the return

Usage

Rounded Boxes

The primary use of this library is for creating Rounded Box polygons, you can do this very simply with boxes.RoundedBox

--- Expensive operation
--- Create a rounded box with a rounding of 10
--- Position of 0, 0
--- And size of 100, 100
local box = boxes.RoundedBox(10, 0, 0, 100, 100)

--- Set the draw color to red
--- And material to Material("vgui/gradient-l")
--- Then call surface.DrawPoly with the box polygon
--- Done!
surface.SetDrawColor(255, 0, 0)
surface.SetMaterial(mat_vgui_gradient_l)
surface.DrawPoly(box)

Per-Vertex Rounding

This library also supports per-vertex rounding, which means, you can have a polygon which looks like the header image above.

This is done very simply with arguments on boxes.RoundedBox

--- Create a rounded box with the same parameters as above
--- But also round each corner differently
--- Note: I do not recommend mixing arg#1 with the individual corner arguments, it seems to have issues I have not diagnosed
local box = boxes.RoundedBox(
  nil, 0, 0, 100, 100, --- rnd, x, y, w, h,
  10, --- Bottom left
  20, --- Top left
  30, --- Top right
  40, --- Bottom right
)

--- Now you can surface.DrawPoly here

Rounded Polygons

At the core of boxes.RoundedBox, is a function called boxes.RoundedPolygonUV, this function simply rounds the vertices of a polygon individually
This function reads a new polygon vertexdata parameter called radius, as seen below

--- Define a polygon
--- Notice the radius parameter on [2], this determines a vertex-specific radii
local poly = {
  {x = 0, y = 0},
  {x = 100, y = 0, radius = 15},
  {x = 0, y = 150}
}

--- Copy and round that polygon with the default radius being 10
--- And provide the bounds of the polygon, for UV purposes
local rounded = boxes.RoundedPolygonUV(poly, 10, 0, 0, 100, 150) --- Furthest right is 100, furthest down is 150

--- And now you can draw it the same as above here