From 2bddfe68bcbf6a9b01a44d8f059ab04f49e6755d Mon Sep 17 00:00:00 2001
From: Eric Mehl <eric@thinkhypothetical.com>
Date: Fri, 2 Aug 2024 11:31:45 -0400
Subject: [PATCH] fixup! ColorChooser : Add `_ColorField` widget

---
 python/GafferUI/ColorChooser.py | 56 +++++++++++++++++++++------------
 1 file changed, 36 insertions(+), 20 deletions(-)

diff --git a/python/GafferUI/ColorChooser.py b/python/GafferUI/ColorChooser.py
index ade3cf2a93..44b9ff5b76 100644
--- a/python/GafferUI/ColorChooser.py
+++ b/python/GafferUI/ColorChooser.py
@@ -387,44 +387,60 @@ def __drawValue( self, painter ) :
 		painter.setBrush( QtGui.QBrush( color ) )
 
 		size = self.size()
+
+		# Use a dot when both axes are a valid value.
 		if position.x >= 0 and position.y >= 0 and position.x <= size.x and position.y <= size.y :
 			painter.drawEllipse( QtCore.QPoint( position.x, position.y ), 4.5, 4.5 )
 			return
 
-		# Draw a triangle pointing out of the field. Prioritize corners to avoid cutting
-		# off part of the triangle out of the field when one axis is right at 0 or size.
-		#        |\  <-- We don't want this overhang.
-		# -------|->
-		#        |/|
-		#          |
-		#          |
-		if position.x >= size.x and position.y <= 0 :
+		triangleWidth = 5.0
+		triangleSpacing = 2.0
+		positionClamped = imath.V2f(
+			min( max( 0.0, position.x ), size.x ),
+			min( max( 0.0, position.y ), size.y )
+		)
+		offset = imath.V2f( 0 )
+		# Use a corner triangle if both axes are invalid values.
+		if position.x > size.x and position.y < 0 :
 			rotation = -45.0  # Triangle pointing to the top-right
-		elif position.x <= 0 and position.y <= 0 :
+			offset = imath.V2f( -triangleSpacing, triangleSpacing )
+		elif position.x < 0 and position.y < 0 :
 			rotation = -135.0  # Top-left
-		elif position.x <= 0 and position.y >= size.y :
+			offset = imath.V2f( triangleSpacing, triangleSpacing )
+		elif position.x < 0 and position.y > size.y :
 			rotation = -225.0  # Bottom-left
-		elif position.x >= size.x and position.y >= size.y :
+			offset = imath.V2f( triangleSpacing, -triangleSpacing )
+		elif position.x > size.x and position.y > size.y :
 			rotation = -315.0  # Bottom-right
+			offset = imath.V2f( -triangleSpacing, -triangleSpacing )
 
-		elif position.x <= size.x and position.x >= 0 and position.y <= 0 :
+		# Finally, use a top / left / bottom / right triangle if one axis is an invalid value.
+		elif position.y < 0 :
 			rotation = -90.0  # Top
-		elif position.x <= 0 and position.y >= 0 and position.y <= size.y :
+			offset = imath.V2f( 0, triangleSpacing )
+			# Clamp it in more to account for the triangle size
+			positionClamped.x = min( max( triangleWidth + triangleSpacing, positionClamped.x ), size.x - triangleWidth - triangleSpacing )
+		elif position.x < 0 :
 			rotation = -180.0  # Left
-		elif position.x >= 0 and position.x <= size.x and position.y >= size.y :
+			offset = imath.V2f( triangleSpacing, 0 )
+			positionClamped.y = min( max( triangleWidth + triangleSpacing, positionClamped.y ), size.y - triangleWidth - triangleSpacing )
+		elif position.y > size.y :
 			rotation = -270.0  # Bottom
+			offset = imath.V2f( 0, -triangleSpacing )
+			positionClamped.x = min( max( triangleWidth + triangleSpacing, positionClamped.x ), size.x - triangleWidth - triangleSpacing )
 		else :
 			rotation = 0.0  # Right
+			offset = imath.V2f( -triangleSpacing, 0 )
+			positionClamped.y = min( max( triangleWidth + triangleSpacing, positionClamped.y ), size.y - triangleWidth - triangleSpacing )
 
-		rightPoints = [ imath.V2f( 0, 0 ), imath.V2f( -6, 5 ), imath.V2f( -6, -5 ) ]
+		rightPoints = [ imath.V2f( 0, 0 ), imath.V2f( -6, triangleWidth ), imath.V2f( -6, -triangleWidth ) ]
 		xform = imath.M33f().rotate( math.radians( rotation ) ) * imath.M33f().translate(
-			imath.V2f(
-				min( max( 0.0, position.x ), size.x ),
-				min( max( 0.0, position.y ), size.y )
-			)
+			positionClamped + offset
 		)
 		points = [ p * xform for p in rightPoints ]
-		points = [ QtCore.QPoint( p.x, p.y ) for p in points ]
+		# Transforming the points introduces slight precision errors which can be noticeable
+		# when drawing polygons. Round the values to compensate.
+		points = [ QtCore.QPoint( round( p.x ), round( p.y ) ) for p in points ]
 
 		painter.drawConvexPolygon( points )