From df717cb9b0386972a93f35f9365d4524134f4aac Mon Sep 17 00:00:00 2001
From: visionmercer <62051836+visionmercer@users.noreply.github.com>
Date: Fri, 22 May 2026 13:56:25 +0200
Subject: [PATCH] Shifty circles

---
 pixler.bas | 63 +++++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 50 insertions(+), 13 deletions(-)

diff --git a/pixler.bas b/pixler.bas
index 6b2eec6..70a149a 100644
--- a/pixler.bas
+++ b/pixler.bas
@@ -450,9 +450,11 @@ sub canvas
         case 2
             do.line state.startx,state.starty,canx,cany,drawcol
         case 3
-            do.circle state.startx,state.starty,sqr((canx-state.startx)^2+(cany-state.starty)^2),drawcol
+            ' Pass current mouse canvas coordinates directly
+            do.circle state.startx,state.starty,canx,cany,drawcol
         case 4
-            do.fcircle state.startx,state.starty,sqr((canx-state.startx)^2+(cany-state.starty)^2),drawcol
+            ' Pass current mouse canvas coordinates directly
+            do.fcircle state.startx,state.starty,canx,cany,drawcol
         case 5
             do.box state.startx,state.starty,canx,cany,drawcol
         case 6
@@ -492,26 +494,19 @@ sub do.line(sx as long,sy as long,ex as long,ey as long,col as long)
         osource=_source
         odest=_dest
 
-        ' --- 45-Degree Angle Snapping Logic ---
         if _keydown(100303) or _keydown(100304) then
             dim dx as single:dx=ex-sx
             dim dy as single:dy=ey-sy
-
             if dx<>0 or dy<>0 then
                 dim linelen as single:linelen=sqr(dx*dx+dy*dy)
                 dim angle as single:angle=_atan2(dy,dx)
-
-                dim pi as single:pi=3.14159265
-                dim degrees as single:degrees=angle*(180.0/pi)
+                dim degrees as single:degrees=angle*(180.0/_pi)
                 dim snappeddegrees as single:snappeddegrees=int((degrees+22.5)/45.0)*45.0
-                dim snappedangle as single:snappedangle=snappeddegrees*(pi/180.0)
-
-                ' FIX: Changed int() to _round() to prevent left/top pixel drifting
+                dim snappedangle as single:snappedangle=snappeddegrees*(_pi/180.0)
                 ex=sx+_round(linelen*cos(snappedangle))
                 ey=sy+_round(linelen*sin(snappedangle))
             end if
         end if
-        ' --------------------------------------
 
         if mouseclicked or rmouseclicked then
             _dest layers(1).ihandle
@@ -527,12 +522,33 @@ sub do.line(sx as long,sy as long,ex as long,ey as long,col as long)
     end if
 end sub
 
-sub do.circle (x as long,y as long,r as long,col as long)
+sub do.circle (sx as long,sy as long,ex as long,ey as long,col as long)
     dim osource as long
     dim odest as long
+    dim x as long,y as long,r as long
+    
     if state.isdrawing then
         osource=_source
         odest=_dest
+        
+        if _keydown(100303) or _keydown(100304) then
+            ' --- Shift Held: Locked Edge Diameter Mode ---
+            ' Calculate the full distance from the start click to the mouse pointer
+            dim diameter as single
+            diameter = sqr((ex - sx) ^ 2 + (ey - sy) ^ 2)
+            
+            r = _round(diameter / 2)
+            
+            ' The center is the exact midpoint between the click and the cursor
+            x = _round((sx + ex) / 2)
+            y = _round((sy + ey) / 2)
+        else
+            ' --- No Shift: Default Center-Radius Mode ---
+            x = sx
+            y = sy
+            r = _round(sqr((ex - sx) ^ 2 + (ey - sy) ^ 2))
+        end if
+
         if mouseclicked or rmouseclicked then
             _dest layers(1).ihandle
             addcommand"circle ("+tst(x)+","+tst(y)+","+tst(int(r))+","+hex$(col)+")"
@@ -546,12 +562,33 @@ sub do.circle (x as long,y as long,r as long,col as long)
     end if
 end sub
 
-sub do.fcircle (x as long,y as long,r as long,col as long)
+sub do.fcircle (sx as long,sy as long,ex as long,ey as long,col as long)
     dim osource as long
     dim odest as long
+    dim x as long,y as long,r as long
+    
     if state.isdrawing then
         osource=_source
         odest=_dest
+        
+        if _keydown(100303) or _keydown(100304) then
+            ' --- Shift Held: Locked Edge Diameter Mode ---
+            ' Calculate the full distance from the start click to the mouse pointer
+            dim diameter as single
+            diameter = sqr((ex - sx) ^ 2 + (ey - sy) ^ 2)
+            
+            r = _round(diameter / 2)
+            
+            ' The center is the exact midpoint between the click and the cursor
+            x = _round((sx + ex) / 2)
+            y = _round((sy + ey) / 2)
+        else
+            ' --- No Shift: Default Center-Radius Mode ---
+            x = sx
+            y = sy
+            r = _round(sqr((ex - sx) ^ 2 + (ey - sy) ^ 2))
+        end if
+
         if mouseclicked or rmouseclicked then
             _dest layers(1).ihandle
             addcommand"fcircle ("+tst(x)+","+tst(y)+","+tst(int(r))+","+hex$(col)+")"