1 files changed, 55 insertions, 0 deletions
diff --git a/dom/canvas/test/webgl-conf/checkout/conformance/ogles/GL/atan/atan_float_frag_xvary_ref.frag b/dom/canvas/test/webgl-conf/checkout/conformance/ogles/GL/atan/atan_float_frag_xvary_ref.frag
new file mode 100644
index 0000000000..83546d9d72
--- /dev/null
+++ b/dom/canvas/test/webgl-conf/checkout/conformance/ogles/GL/atan/atan_float_frag_xvary_ref.frag
@@ -0,0 +1,55 @@
+
+/*
+Copyright (c) 2019 The Khronos Group Inc.
+Use of this source code is governed by an MIT-style license that can be
+found in the LICENSE.txt file.
+*/
+
+
+#ifdef GL_ES
+precision mediump float;
+#endif
+varying vec4 color;
+
+void main (void)
+{
+	const float M_PI = 3.14159265358979323846;
+	float c = 4.0 * 2.0 * (color.r - 0.5);
+	float atan_c = 0.0;
+	float scale = 1.0;
+	float sign = 1.0;
+	vec4 result;
+
+	if(c < 0.0)
+	{
+		sign = -1.0;
+		c *= -1.0;
+	}
+
+	if(c <= 1.0)
+	{
+		// Taylors series expansion for atan
+		for(int i = 1; i < 12; i += 2)
+		{
+			atan_c += scale * pow(c, float(i)) / float(i);
+			scale *= -1.0;
+		}
+
+		result = vec4(sign * atan_c / M_PI + 0.5, 0.0, 0.0, 1.0);
+	}
+	else
+	{
+		c = 1.0 / c;
+
+		// Taylors series expansion for atan
+		for(int i = 1; i < 12; i += 2)
+		{
+			atan_c += scale * pow(c, float(i)) / float(i);
+			scale *= -1.0;
+		}
+
+		result = vec4(sign * (M_PI / 2.0 - atan_c) / M_PI + 0.5, 0.0, 0.0, 1.0);
+	}
+
+	gl_FragColor = result;
+}