src/game: add a gui module with a border generator

sonic-radiance.love/game/modules/gui/init.lua

@@ -0,0 +1,41 @@
+local gui = {}
+
+function gui.newBorder(width, height, middlePosition)
+  local tileset   = love.graphics.newImage("assets/gui/borders.png")
+  local tilequad  = {}
+  local w, h = tileset:getDimensions()
+  tilequad[1]     = love.graphics.newQuad(0, 0, 20, 20, w, h)
+  tilequad[2]     = love.graphics.newQuad(20, 0, 20, 20, w, h)
+  tilequad[3]     = love.graphics.newQuad(40, 0, 20, 20, w, h)
+  tilequad[4]     = love.graphics.newQuad(60, 0, 20, 20, w, h)
+
+  local Texture = love.graphics.newCanvas(width, height)
+
+  love.graphics.setCanvas(Texture)
+  utils.graphics.resetColor()
+
+  local height  = math.ceil(height / 20)
+  local width   = math.ceil(width  / 20)
+
+  for i=1, width do
+    if i < middlePosition then
+      love.graphics.draw(tileset, tilequad[1], (i-1) * 20, 0)
+    elseif (i == middlePosition) then
+      love.graphics.draw(tileset, tilequad[2], (i-1) * 20, 0)
+    else
+      love.graphics.draw(tileset, tilequad[3], (i-1) * 20, 0)
+    end
+
+    if height > 1 then
+      for j = 2, height do
+        love.graphics.draw(tileset, tilequad[4], (i-1) * 20, (j-1) * 20)
+      end
+    end
+  end
+
+  love.graphics.setCanvas( )
+
+  return Texture
+end
+
+return gui