From 6b50de5e356ebdee7748bdacfe7aca4c361b8b1f Mon Sep 17 00:00:00 2001
From: "Edgar P. Burkhart" <git@edgarpierre.fr>
Date: Sun, 31 Dec 2023 18:41:54 +0100
Subject: [PATCH] Fix opacity calculation on chrome

---
 nummi/history/templates/history/plot.html | 3 +--
 nummi/main/templatetags/main_extras.py    | 7 +++++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/nummi/history/templates/history/plot.html b/nummi/history/templates/history/plot.html
index 1f0d858..399bc4e 100644
--- a/nummi/history/templates/history/plot.html
+++ b/nummi/history/templates/history/plot.html
@@ -102,8 +102,7 @@
                         {% endif %}
                         {% if m %}
                             <td class="{% if m.sum > 0 %}p{% else %}m{% endif %}"
-                                style="opacity: calc( sin( abs({% widthratio m.sum history.years_max 100 %}) / 400 * 1turn ) )">
-                            </td>
+                                style="opacity: {% opacity m.sum history.years_max %}"></td>
                         {% else %}
                             <td></td>
                         {% endif %}
diff --git a/nummi/main/templatetags/main_extras.py b/nummi/main/templatetags/main_extras.py
index a85d8db..670bda9 100644
--- a/nummi/main/templatetags/main_extras.py
+++ b/nummi/main/templatetags/main_extras.py
@@ -1,3 +1,5 @@
+import math
+
 from django import template
 from django.templatetags.static import static
 from django.utils import formats
@@ -67,3 +69,8 @@ def css(href):
     return mark_safe(
         f"""<link rel="stylesheet" href="{static(href)}" type="text/css">"""
     )
+
+
+@register.simple_tag
+def opacity(v, vmax):
+    return f"{math.sin(math.fabs(v/vmax)*math.pi/2):.2f}"