main.lua

UI = require "lib.UI"
v2 = require "lib.v2"
require "kirkpatrick"

font_body = love.graphics.newFont("Cantarell-Regular.otf", 15)
font_title = love.graphics.newFont("Cantarell-Regular.otf", 18)
love.graphics.setLineJoin("bevel")

UI.font = font_body

function love.load()
   canvas = love.graphics.newCanvas()
   love.graphics.setBackgroundColor{ 1,1,1 }
   state = "drawing"
   drawn_layer = layer

   debug = false
   drawing_history = {}
   removed = {}
   edges = {}
   polygon = {}
   layers = {}
   mouse_position = v2(0,0)
   ui_width = 0
end

function love.mousepressed(x, y, button)
   if button == 1 then
      UI.mousepressed { x = x, y = y }
   end
end

function love.mousereleased(x, y, button)
   if button == 1 then
      UI.mousereleased { x = x, y = y }
      if state == "none" then
         -- do nothing
      elseif state == "search" then
         point_to_find = mouse_position
         state = "none"
      elseif state == "drawing" and mouse_position.x > ui_width + 10 then

         local to = mouse_position
         first = first or to

         if not edges[to] then edges[to] = {} end
         if last and (to == last or to == first) and #polygon > 2 
         then
            triangulate(edges, polygon, region_id)
            polygon = {}
            table.insert(drawing_history, region_id)
            first = nil
            last = nil
            generate_id()
         else
            last = to
            table.insert(polygon, to)
         end

         if edges then removed[layer] = independent(edges) end
      end
   end
end

function love.mousemoved(x, y)
   mouse_position = v2(x,y)
   snapped = false

   local closest
   local min_dist = math.huge
   for point,_ in pairs(edges) do
      local dist = (point - mouse_position):len()
      if dist < 15 and dist < min_dist then
         closest = point
         snapped = true
         min_dist = dist
      end
   end
   mouse_position = closest or mouse_position

   UI.mousemoved { x = x, y = y }
end

function love.resize()
   canvas = love.graphics.newCanvas()
end


-- Drawing

function love.draw()
   love.graphics.setCanvas(canvas)
   love.graphics.clear()
   for l = 1,drawn_layer do
      for i = 1,region_id do
         if triangles[i] then
            draw_region(i, l)
         end
      end
      if removed[drawn_layer] then
         for _,point in ipairs(removed[drawn_layer]) do
            love.graphics.setColor(1,1,1)
            love.graphics.circle("fill", point.x, point.y, 10)
            love.graphics.setColor(0,0,0)
            love.graphics.circle("line", point.x, point.y, 10)
            love.graphics.setColor(1,1,1)
         end
      end
   end
   if state == "drawing" and polygon then 
      draw_unfinished(polygon) 
   end
   view()
   if snapped then draw_red_point(mouse_position) end
   if point_to_find then draw_red_point(point_to_find) end
   love.graphics.setCanvas()
   love.graphics.draw(canvas)
end

function draw_red_point(p)
   local ps = love.graphics.getPointSize()
   love.graphics.setPointSize(10)
   love.graphics.points({{ p.x, p.y, .8,0,0,1 }})
   love.graphics.setPointSize(ps)
end

function draw_unfinished(polygon)
   local r,g,b,a = love.graphics.getColor()
   local ps = love.graphics.getPointSize()
   local lw = love.graphics.getLineWidth()
   local shape = {}

   for _,point in ipairs(polygon) do
      table.insert(shape, point.x)
      table.insert(shape, point.y)
   end

   if mouse_position.x > ui_width + 10 then
      table.insert(shape, mouse_position.x)
      table.insert(shape, mouse_position.y)
   end

   love.graphics.setLineWidth(2)
   love.graphics.setColor(0,0,0,.5)
   if #shape > 4 then love.graphics.polygon("fill", shape) end
   love.graphics.setColor(0,0,0,1)
   if #shape > 4 then love.graphics.polygon("line", shape) end
   love.graphics.setPointSize(6)
   love.graphics.points(shape)

   love.graphics.setLineWidth(lw)
   love.graphics.setPointSize(ps)
   love.graphics.setColor(r,g,b,a)
end

function view()
   ui_width, ui_height = UI.draw { x = 10, y = 10,
      UI.button { "debug", on_click = function() debug = not debug end },
      UI.button { "Refine triangulation", on_click = function() 
         state = "none"
         layers[layer] = edges
         local to_remove = removed[layer]
         if to_remove and #to_remove > 0 then
            layer = layer + 1
            edges = step_algorithm(edges, to_remove)
            drawn_layer = layer
            removed[layer] = independent(edges)
         end
      end },
      UI.label {""},
      UI.button { "Up", on_click = function() drawn_layer = math.min(layer, drawn_layer + 1) end },
      UI.button { "Down", on_click = function() drawn_layer = math.max(1, drawn_layer - 1) end },
      UI.button { "Find point", on_click = function() state = "search" end },
      UI.label { ("Punkt %s:"):format(point_to_find) },
   }
   if state == "drawing" then
      UI.draw { x = 10, y = ui_height + 30,
         UI.button { "Undo", on_click = function() 
            region_remove(edges, drawing_history[#drawing_history])
            table.remove(drawing_history)
            removed[layer] = independent(edges)
         end },
      }
   else
      UI.draw { x = ui_width + 30, y = 10,
         {
            UI.label { ("[%d] layer"):format(drawn_layer), font = font_title },
            point_to_find and UI.label { find_point(point_to_find) or "Point out of region", font = font_title },
         }
      }
   end

   love.graphics.line(ui_width + 20, 0, ui_width + 20, 2000)
end