From d8c17c429eef3c352239b1d1350ea7091afe672e Mon Sep 17 00:00:00 2001
From: Travis Shears <t@travisshears.com>
Date: Sat, 5 Jul 2025 21:03:04 +0200
Subject: [PATCH] write pixels to canvas and preview

---
 one_line/main.fnl | 83 ++++++++++++++++++++++++++++++++++-------------
 1 file changed, 60 insertions(+), 23 deletions(-)

diff --git a/one_line/main.fnl b/one_line/main.fnl
index b6d5782..cd6a0db 100644
--- a/one_line/main.fnl
+++ b/one_line/main.fnl
@@ -1,26 +1,70 @@
-
-(tset _G :img-width 88)
-(tset _G :img-height 31)
-
 (local scale 6)
-(tset _G :canvas-width (* scale (. _G :img-width)))
-(tset _G :canvas-height (* scale (. _G :img-height)))
+(local canvas-w (* scale 88))
+(local canvas-h (* scale 31))
+(local canvas-x (* -1 (/ canvas-w 2)))
+(local canvas-y (* -1 (/ canvas-h 2)))
+(local theme {
+  :white (lambda [cb] (cb (love.math.colorFromBytes 247 246 246)))
+  :black (lambda [cb] (cb (love.math.colorFromBytes 60 54 51)))
+})
 
 (lambda set-center-origin []
   (let [(w h f) (love.window.getMode)
     x (/ w 2)
     y (/ h 2)
     ]
-    ; (print (..  "setting orgin to middle of window: " x "," y))
     (love.graphics.push)
     (love.graphics.translate x y)))
 
+; setup pixels for image that we are drawing
+(var pixel-canvas nil)
+(local pixels {})
+(tset pixels :ordered-keys [])
+(tset pixels :cords {})
+(for [y 1 31]
+  (for [x 1 88]
+    (let [key (.. x "," y)]
+      (tset pixels.cords key {: x : y :val false})
+      (table.insert pixels.ordered-keys key))))
+
+(fn draw-canvases []
+  "Draw main drawing canvas and preview canvas to screen"
+  (pixel-canvas:setFilter "nearest" "nearest")
+  (love.graphics.draw pixel-canvas canvas-x canvas-y 0 scale scale)
+  (love.graphics.draw pixel-canvas canvas-x (- canvas-y 60)))
+
+(fn update-canvas []
+  (love.graphics.setCanvas pixel-canvas)
+  (love.graphics.clear 0 0 0 0)
+  (each [key {: x  : y : val} (pairs pixels.cords)]
+    (when val (love.graphics.points x y)))
+  (love.graphics.setCanvas)
+)
+
+(fn love.update []
+  (let [
+    (w h _) (love.window.getMode)
+    (mouse-x-raw mouse-y-raw) (love.mouse.getPosition)
+    mouse-x (- mouse-x-raw (/ w 2))
+    mouse-y (- mouse-y-raw (/ h 2))
+    ]
+    (when (and (> mouse-x canvas-x) (> mouse-y canvas-y) (< mouse-x (+ canvas-x canvas-w)) (< mouse-y (+ canvas-y canvas-h)))
+      (let [
+        x (+ 1 (math.floor (/ (+ (/ canvas-w 2) mouse-x) scale)))
+        y (+ 1 (math.floor (/ (+ (/ canvas-h 2) mouse-y) scale)))
+        key (.. x "," y)
+        ]
+        (tset (. pixels.cords key) :val true)
+        (update-canvas)
+        (print (.. x "," y))))))
+
 (fn love.load []
   ;; 480p 720×480
   (love.window.setMode  720 480)
-  ; (set-center-origin)
-  ; (love.graphics.pop)
 
+  ; prep canvas
+  (set pixel-canvas (love.graphics.newCanvas 88 31))
+  (update-canvas)
 
   ;; start a thread listening on stdin
   (: (love.thread.newThread "require('love.event')
@@ -31,29 +75,22 @@ while 1 do love.event.push('stdin', io.read('*line')) end") :start))
   (let [(ok val) (pcall fennel.eval line)]
     (print (if ok (fennel.view val) val))))
 
-
 (lambda draw-static-bg []
-  (let [
-    canvas-w (* scale 88)
-    canvas-h (* scale 31)
-    canvas-x (* -1 (/ canvas-w 2))
-    canvas-y (* -1 (/ canvas-h 2))
-    ]
-    ; canvas
+    ; canvas outline and text
     (love.graphics.print "Canvas:" canvas-x (- canvas-y 20))
     (love.graphics.rectangle "line" canvas-x canvas-y canvas-w canvas-h)
-    ; preview
+    ; preview outline and text
     (love.graphics.print "Preview:" canvas-x (- canvas-y 80))
     (love.graphics.rectangle "line" canvas-x (- canvas-y 60) 89 32)
-    )
 )
 
 (fn love.draw []
   (set-center-origin)
-  (love.graphics.setBackgroundColor (love.math.colorFromBytes 192 192 192))
-  (love.graphics.setColor (love.math.colorFromBytes 29 29 29))
+  (theme.white love.graphics.setBackgroundColor)
+  (theme.black love.graphics.setColor)
   (draw-static-bg)
+  (draw-canvases)
   (love.graphics.pop))
 
-(fn love.keypressed [key]
-  (love.event.quit))
+; (fn love.keypressed [key]
+  ; (love.event.quit))