#63 rectangle element

graphics/core.lua

@@ -30,6 +30,20 @@ graphics.TEXT_ALIGN = {
     RIGHT = 3
 }
 
+---@class graphics_border
+---@field width integer
+---@field color color
+
+---@param width integer
+---@param color color
+---@return graphics_border
+function graphics.border(width, color)
+    return {
+        width = width,
+        color = color
+    }
+end
+
 ---@class graphics_frame
 ---@field x integer
 ---@field y integer

graphics/element.lua

@@ -23,6 +23,7 @@ function element.new(args)
 
     local protected = {
         window = nil,   ---@type table
+        fg_bg = core.graphics.cpair(colors.white, colors.black),
         frame = core.graphics.gframe(1, 1, 1, 1)
     }
 
@@ -56,6 +57,7 @@ function element.new(args)
         protected.window.setBackgroundColor(args.fg_bg.bkg)
         protected.window.setTextColor(args.fg_bg.fgd)
         protected.window.clear()
+        protected.fg_bg = args.fg_bg
     end
 
     -- record position

graphics/elements/rectangle.lua

@@ -0,0 +1,64 @@
+-- Rectangle Graphics Element
+
+local element = require("graphics.element")
+
+---@class rectangle_args
+---@field border? graphics_border
+---@field parent graphics_element
+---@field x? integer 1 if omitted
+---@field y? integer 1 if omitted
+---@field width? integer parent width if omitted
+---@field height? integer parent height if omitted
+---@field gframe? graphics_frame frame instead of x/y/width/height
+---@field fg_bg cpair foreground/background colors
+
+-- new rectangle
+---@param args rectangle_args
+local function rectangle(args)
+    -- create new graphics element rectangle object
+    local e = element.new(args)
+
+    -- draw bordered box if requested
+    -- element constructor will have drawn basic colored rectangle regardless
+    if args.border ~= nil then
+        e.setCursorPos(1, 1)
+
+        local border_width = args.border.width
+        local border_blit = colors.toBlit(args.border.color)
+        local spaces = ""
+        local blit_fg = ""
+        local blit_bg_top_bot = ""
+        local blit_bg_sides = ""
+
+        -- form the basic and top/bottom blit strings
+        for _ = 1, e.frame.w do
+            spaces = spaces .. " "
+            blit_fg = blit_fg .. e.fg_bg.blit_fgd
+            blit_bg_top_bot = blit_bg_top_bot .. border_blit
+        end
+
+        -- form the body blit strings (sides are border, inside is normal)
+        for x = 1, e.frame.w do
+            -- edges get border color, center gets normal
+            if x <= border_width or x > (e.frame.w - border_width) then
+                blit_bg_sides = blit_bg_sides .. border_blit
+            else
+                blit_bg_sides = blit_bg_sides .. e.fg_bg.blit_bkg
+            end
+        end
+
+        -- draw rectangle with borders
+        for y = 1, e.frame.h do
+            e.setCursorPos(y, 1)
+            if y <= border_width or y > (e.frame.h - border_width) then
+                e.blit(spaces, blit_fg, blit_bg_top_bot)
+            else
+                e.blit(spaces, blit_fg, blit_bg_sides)
+            end
+        end
+    end
+
+    return e.get()
+end
+
+return rectangle