pipe indicator graphics element

graphics/elements/indicators/pipe.lua

@@ -0,0 +1,110 @@
+-- Pipe Graphics Element
+
+local util    = require("scada-common.util")
+
+local element = require("graphics.element")
+
+---@class pipe_args
+---@field parent graphics_element
+---@field x? integer 1 if omitted
+---@field y? integer 1 if omitted
+---@field end_x integer end of pipe
+---@field end_y integer end of pipe
+---@field thin boolean true for 1 subpixels, false (default) for 2
+---@field align_tr? boolean false to align bottom left (default), true to align top right
+---@field fg_bg? cpair foreground/background colors
+
+-- new pipe
+---@param args pipe_args
+local function pipe(args)
+    assert(util.is_int(args.end_x), "graphics.elements.indicators.pipe: end_x is a required field")
+    assert(util.is_int(args.end_y), "graphics.elements.indicators.pipe: end_y is a required field")
+
+    args.x = args.x or 1
+    args.y = args.y or 1
+    args.width = args.end_x - args.x
+    args.height = args.end_y - args.y
+
+    -- create new graphics element base object
+    local e = element.new(args)
+
+    -- draw pipe
+
+    local align_tr = args.align_tr or false
+
+    local x = 1
+    local y = 1
+
+    if align_tr then
+        -- cross width then height
+        for i = 1, args.width do
+            if args.thin then
+                if i == args.width then
+                    -- corner
+                    e.window.blit("\x93", e.fg_bg.blit_bkg, e.fg_bg.blit_fgd)
+                else
+                    e.window.blit("\x8c", e.fg_bg.blit_fgd, e.fg_bg.blit_bkg)
+                end
+            else
+                if i == args.width then
+                    -- corner
+                    e.window.blit(" ", e.fg_bg.blit_bkg, e.fg_bg.blit_fgd)
+                else
+                    e.window.blit("\x8f", e.fg_bg.blit_fgd, e.fg_bg.blit_bkg)
+                end
+            end
+
+            x = x + 1
+            e.window.setCursorPos(x, y)
+        end
+
+        -- back up one
+        x = x - 1
+
+        for _ = 1, args.height do
+            y = y + 1
+            e.window.setCursorPos(x, y)
+
+            if args.thin then
+                e.window.blit("\x95", e.fg_bg.blit_bkg, e.fg_bg.blit_fgd)
+            else
+                e.window.blit(" ", e.fg_bg.blit_bkg, e.fg_bg.blit_fgd)
+            end
+        end
+    else
+        -- cross height then width
+        for i = 1, args.height do
+            if args.thin then
+                if i == args.height then
+                    -- corner
+                    e.window.blit("\x8d", e.fg_bg.blit_fgd, e.fg_bg.blit_bkg)
+                else
+                    e.window.blit("\x95", e.fg_bg.blit_fgd, e.fg_bg.blit_bkg)
+                end
+            else
+                e.window.blit(" ", e.fg_bg.blit_bkg, e.fg_bg.blit_fgd)
+            end
+
+            y = y + 1
+            e.window.setCursorPos(x, y)
+        end
+
+        -- back up one
+        y = y - 1
+
+        for _ = 1, args.width do
+            x = x + 1
+            e.window.setCursorPos(x, y)
+
+            if args.thin then
+                e.window.blit("\x8c", e.fg_bg.blit_fgd, e.fg_bg.blit_bkg)
+            else
+                e.window.blit("\x83", e.fg_bg.blit_bkg, e.fg_bg.blit_fgd)
+            end
+        end
+    end
+
+    return e.get()
+end
+
+return pipe