From 482b92d700bc544c3ce65fc1a7aaba2c4792c24c Mon Sep 17 00:00:00 2001
From: KIU Shueng Chuan <nixchuan@gmail.com>
Date: Tue, 3 Aug 2021 20:29:11 +0800
Subject: [PATCH] GLGradientLegendItem: remove opengl code

change fontColor to take a mkColor() argument

use hyperlink when referring to other functions
---
 .../opengl/items/GLGradientLegendItem.py      | 70 ++++++-------------
 1 file changed, 23 insertions(+), 47 deletions(-)

diff --git a/pyqtgraph/opengl/items/GLGradientLegendItem.py b/pyqtgraph/opengl/items/GLGradientLegendItem.py
index 1409a160..eb33a886 100644
--- a/pyqtgraph/opengl/items/GLGradientLegendItem.py
+++ b/pyqtgraph/opengl/items/GLGradientLegendItem.py
@@ -1,6 +1,6 @@
 from ... Qt import QtCore, QtGui
 from ... import functions as fn
-from OpenGL.GL import *
+from ... colormap import ColorMap
 from ..GLGraphicsItem import GLGraphicsItem
 
 __all__ = ['GLGradientLegendItem']
@@ -18,7 +18,8 @@ class GLGradientLegendItem(GLGraphicsItem):
             gradient: a pg.ColorMap used to color the colorbar
             labels: a dict of "text":value to display next to the colorbar.
                 The value corresponds to a position in the gradient from 0 to 1.
-            fontColor: sets the color of the texts
+            fontColor: sets the color of the texts. Accepts any single argument accepted by
+                :func:`~pyqtgraph.mkColor`
             #Todo:
                 size as percentage
                 legend title
@@ -28,10 +29,12 @@ class GLGradientLegendItem(GLGraphicsItem):
         self.setGLOptions(glopts)
         self.pos = (10, 10)
         self.size = (10, 100)
-        self.fontColor = (1.0, 1.0, 1.0, 1.0)
-        self.stops = None
-        self.colors = None
-        self.gradient = None
+        self.fontColor = QtGui.QColor(QtCore.Qt.GlobalColor.white)
+        # setup a default trivial gradient
+        stops = (0.0, 1.0)
+        self.gradient = ColorMap(pos=stops, color=(0.0, 1.0))
+        self._gradient = None
+        self.labels = {str(x) : x for x in stops}
         self.setData(**kwds)
 
     def setData(self, **kwds):
@@ -45,54 +48,31 @@ class GLGradientLegendItem(GLGraphicsItem):
 
         self.antialias = False
 
-        for arg in args:
-            if arg in kwds:
-                setattr(self, arg, kwds[arg])
+        for key in kwds:
+            value = kwds[key]
+            if key == 'fontColor':
+                value = fn.mkColor(value)
+            elif key == 'gradient':
+                self._gradient = None
+            setattr(self, key, value)
 
         ##todo: add title
         ##todo: take more gradient types
-        if self.gradient is not None and hasattr(self.gradient, "getStops"):
-            self.stops, self.colors = self.gradient.getStops("float")
-            self.qgradient = self.gradient.getGradient()
         self.update()
 
     def paint(self):
-        if self.pos is None or self.stops is None:
-            return
         self.setupGLState()
-        glMatrixMode(GL_PROJECTION)
-        glPushMatrix()
-        glLoadIdentity()
-        glOrtho(0.0, self.view().width(), self.view().height(), 0.0, -1.0, 10.0)
-        glMatrixMode(GL_MODELVIEW)
-        glLoadIdentity()
-        glDisable(GL_CULL_FACE)
 
-        glClear(GL_DEPTH_BUFFER_BIT)
+        if self._gradient is None:
+            self._gradient = self.gradient.getGradient()
 
-        # draw the colorbar
-        glTranslate(self.pos[0], self.pos[1], 0)
-        glScale(self.size[0], self.size[1], 0)
-        glBegin(GL_QUAD_STRIP)
-        for p, c in zip(self.stops, self.colors):
-            glColor4f(*c)
-            glVertex2d(0, 1 - p)
-            glColor4f(*c)
-            glVertex2d(1, 1 - p)
-        glEnd()
-
-        # draw labels
-        # scaling and translate doesnt work on rendertext
-        fontColor = QtGui.QColor(*[x * 255 for x in self.fontColor])
-
-        # could also draw the gradient using QPainter
-        barRect = QtCore.QRectF(self.view().width() - 60, self.pos[1], self.size[0], self.size[1])
-        self.qgradient.setStart(barRect.bottomLeft())
-        self.qgradient.setFinalStop(barRect.topLeft())
+        barRect = QtCore.QRectF(self.pos[0], self.pos[1], self.size[0], self.size[1])
+        self._gradient.setStart(barRect.bottomLeft())
+        self._gradient.setFinalStop(barRect.topLeft())
 
         painter = QtGui.QPainter(self.view())
-        painter.fillRect(barRect, self.qgradient)
-        painter.setPen(fn.mkPen(fontColor))
+        painter.fillRect(barRect, self._gradient)
+        painter.setPen(self.fontColor)
         for labelText, labelPosition in self.labels.items():
             ## todo: draw ticks, position text properly
             x = 1.1 * self.size[0] + self.pos[0]
@@ -101,7 +81,3 @@ class GLGradientLegendItem(GLGraphicsItem):
             painter.drawText(x, y, labelText)
         painter.end()
 
-        glMatrixMode(GL_PROJECTION)
-        glPopMatrix()
-        glMatrixMode(GL_MODELVIEW)
-