From 1b553478f6e0a0fa5c333409cb81f603aff0e8a3 Mon Sep 17 00:00:00 2001
From: Benjamin Otte <otte@redhat.com>
Date: Mon, 19 Dec 2016 23:30:02 +0100
Subject: [PATCH] cssimageradial: Handle "partial" gradients correctly

When the first/last color stop is not at 0%/100%, we need to start the
repeating at their offsets and not at 0%/100%.

Attached reftest demonstrates the problem.
---
 gtk/gtkcssimageradial.c                               |  2 +-
 testsuite/reftests/Makefile.am                        |  3 +++
 .../repeating-radial-gradient-at-beginning.css        | 11 +++++++++++
 .../repeating-radial-gradient-at-beginning.ref.ui     | 11 +++++++++++
 .../repeating-radial-gradient-at-beginning.ui         | 10 ++++++++++
 5 files changed, 36 insertions(+), 1 deletion(-)
 create mode 100644 testsuite/reftests/repeating-radial-gradient-at-beginning.css
 create mode 100644 testsuite/reftests/repeating-radial-gradient-at-beginning.ref.ui
 create mode 100644 testsuite/reftests/repeating-radial-gradient-at-beginning.ui

diff --git a/gtk/gtkcssimageradial.c b/gtk/gtkcssimageradial.c
index e22d9b805b..585d136d2c 100644
--- a/gtk/gtkcssimageradial.c
+++ b/gtk/gtkcssimageradial.c
@@ -163,7 +163,7 @@ gtk_css_image_radial_draw (GtkCssImage *image,
 
   gtk_css_image_radial_get_start_end (radial, radius, &start, &end);
 
-  pattern = cairo_pattern_create_radial (0, 0, 0, 0, 0, radius);
+  pattern = cairo_pattern_create_radial (0, 0, radius * start, 0, 0, radius * end);
   if (yscale != 1.0)
     {
       cairo_matrix_init_scale (&matrix, 1.0, 1.0 / yscale);
diff --git a/testsuite/reftests/Makefile.am b/testsuite/reftests/Makefile.am
index c0c1beab68..2dbca1209c 100644
--- a/testsuite/reftests/Makefile.am
+++ b/testsuite/reftests/Makefile.am
@@ -377,6 +377,9 @@ testdata = \
 	quit-mnemonic.css \
 	quit-mnemonic.ref.ui \
 	quit-mnemonic.ui \
+	repeating-radial-gradient-at-beginning.css \
+	repeating-radial-gradient-at-beginning.ref.ui \
+	repeating-radial-gradient-at-beginning.ui \
 	reset-to-defaults.css \
 	revealer-extra-size.ref.ui \
 	revealer-extra-size.ui \
diff --git a/testsuite/reftests/repeating-radial-gradient-at-beginning.css b/testsuite/reftests/repeating-radial-gradient-at-beginning.css
new file mode 100644
index 0000000000..0f4dd2eef6
--- /dev/null
+++ b/testsuite/reftests/repeating-radial-gradient-at-beginning.css
@@ -0,0 +1,11 @@
+window {
+  background: repeating-radial-gradient(red 50%, blue, red);
+}
+
+#reference {
+  background-image: radial-gradient(red, blue, red), repeating-radial-gradient(red 50%, blue, red);
+  background-size: 50% 50%, 100% 100%;
+  background-repeat: no-repeat;
+  background-position: center;
+}
+
diff --git a/testsuite/reftests/repeating-radial-gradient-at-beginning.ref.ui b/testsuite/reftests/repeating-radial-gradient-at-beginning.ref.ui
new file mode 100644
index 0000000000..3f0f3f1d4a
--- /dev/null
+++ b/testsuite/reftests/repeating-radial-gradient-at-beginning.ref.ui
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<interface>
+  <!-- interface-requires gtk+ 3.0 -->
+  <object class="GtkWindow" id="window1">
+    <property name="width_request">64</property>
+    <property name="height_request">32</property>
+    <property name="can_focus">False</property>
+    <property name="type">popup</property>
+    <property name="name">reference</property>
+  </object>
+</interface>
diff --git a/testsuite/reftests/repeating-radial-gradient-at-beginning.ui b/testsuite/reftests/repeating-radial-gradient-at-beginning.ui
new file mode 100644
index 0000000000..a6c83b876a
--- /dev/null
+++ b/testsuite/reftests/repeating-radial-gradient-at-beginning.ui
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<interface>
+  <!-- interface-requires gtk+ 3.0 -->
+  <object class="GtkWindow" id="window1">
+    <property name="width_request">64</property>
+    <property name="height_request">32</property>
+    <property name="can_focus">False</property>
+    <property name="type">popup</property>
+  </object>
+</interface>