tests with a striped background for ciecam-sliders...

gui/colors/adjbases.py

@@ -985,6 +985,25 @@ def render_background_cb(self, cr, wd, ht):
         b_w = wd - b - b - 1
         b_h = ht - b - b - 1
 
+        # Build a background (wip and very hacky!!!)
+        # temporarly check type to only show in these sliders...
+        from gui.colors.sliders import CIECAMLumaSlider, CIECAMChromaSlider, CIECAMHueSlider
+        if isinstance(self, (CIECAMLumaSlider, CIECAMChromaSlider, CIECAMHueSlider)):
+            if self.vertical:
+                stripes_gradient = cairo.LinearGradient(0, b, bar_length / 4, b + bar_length)
+            else:
+                stripes_gradient = cairo.LinearGradient(b, 0, b + bar_length, bar_length / 4)
+            num_stripes = int(bar_length / 2)  # 2px per line, high dpi scaling? :)
+            for s in xrange(num_stripes):
+                p = s / num_stripes
+                r = g = b = 1  # white lines
+                if s % 2 == 0:
+                    r = g = b = 0  # black lines
+                stripes_gradient.add_color_stop_rgba(p, r, g, b, 0.4)
+            cr.set_source(stripes_gradient)
+            cr.rectangle(b_x - 0.5, b_y - 0.5, b_w + 1, b_h + 1)
+            cr.fill()
+
         # Build the gradient
         if self.vertical:
             bar_gradient = cairo.LinearGradient(0, b, 0, b + bar_length)
@@ -995,9 +1014,21 @@ def render_background_cb(self, cr, wd, ht):
             p = s / samples
             col = self.get_color_for_bar_amount(p)
             r, g, b = col.get_rgb()
+            a = 1
+
+            if isinstance(self, (CIECAMLumaSlider, CIECAMChromaSlider, CIECAMHueSlider)):
+                # assume grey means invalid color
+                # TODO: need actual alpha in given color (return separate rgba color for sliders maybe?)
+                # TODO: "position" is inaccurate, more samples?
+                if r == g == b:
+                    r = g = b = 0.4
+                    a = 0
+                    # test for clean cut
+                    bar_gradient.add_color_stop_rgba(p - (1 / samples - 0.0001), r, g, b, a)
+                    bar_gradient.add_color_stop_rgba(p + (1 / samples - 0.0001), r, g, b, a)
             if self.vertical:
                 p = 1 - p
-            bar_gradient.add_color_stop_rgb(p, r, g, b)
+            bar_gradient.add_color_stop_rgba(p, r, g, b, a)
 
         # Paint bar with Tango-like edges
         cr.set_line_join(cairo.LINE_JOIN_ROUND)