diff --git a/tests/visual_tests/grids/group-symbolizer-3-512-256-1.0-grid-reference.json b/tests/visual_tests/grids/group-symbolizer-3-512-256-1.0-grid-reference.json
new file mode 100644
index 000000000..ef2ac14e2
--- /dev/null
+++ b/tests/visual_tests/grids/group-symbolizer-3-512-256-1.0-grid-reference.json
@@ -0,0 +1,74 @@
+{
+ "keys": [
+  "", 
+  "1", 
+  "2"
+ ], 
+ "data": {}, 
+ "grid": [
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                         !                                            #                                         ", 
+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                "
+ ]
+}
\ No newline at end of file
diff --git a/tests/visual_tests/grids/group-symbolizer-3-512-256-2.0-grid-reference.json b/tests/visual_tests/grids/group-symbolizer-3-512-256-2.0-grid-reference.json
new file mode 100644
index 000000000..ef2ac14e2
--- /dev/null
+++ b/tests/visual_tests/grids/group-symbolizer-3-512-256-2.0-grid-reference.json
@@ -0,0 +1,74 @@
+{
+ "keys": [
+  "", 
+  "1", 
+  "2"
+ ], 
+ "data": {}, 
+ "grid": [
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                         !                                            #                                         ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
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+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                ", 
+  "                                                                                                                                "
+ ]
+}
\ No newline at end of file
diff --git a/tests/visual_tests/images/group-symbolizer-3-512-256-1.0-agg-reference.png b/tests/visual_tests/images/group-symbolizer-3-512-256-1.0-agg-reference.png
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diff --git a/tests/visual_tests/images/group-symbolizer-3-512-256-1.0-cairo-reference.png b/tests/visual_tests/images/group-symbolizer-3-512-256-1.0-cairo-reference.png
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diff --git a/tests/visual_tests/images/group-symbolizer-3-512-256-2.0-agg-reference.png b/tests/visual_tests/images/group-symbolizer-3-512-256-2.0-agg-reference.png
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diff --git a/tests/visual_tests/images/group-symbolizer-3-512-256-2.0-cairo-reference.png b/tests/visual_tests/images/group-symbolizer-3-512-256-2.0-cairo-reference.png
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