1 files changed, 72 insertions, 0 deletions
diff --git a/dom/canvas/test/webgl-conf/checkout/conformance/ogles/GL/acos/acos_vec3_vert_xvary_ref.vert b/dom/canvas/test/webgl-conf/checkout/conformance/ogles/GL/acos/acos_vec3_vert_xvary_ref.vert
new file mode 100644
index 0000000000..37ace0f04f
--- /dev/null
+++ b/dom/canvas/test/webgl-conf/checkout/conformance/ogles/GL/acos/acos_vec3_vert_xvary_ref.vert
@@ -0,0 +1,72 @@
+
+/*
+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.
+*/
+
+
+attribute vec4 gtf_Vertex;
+attribute vec4 gtf_Color;
+uniform mat4 gtf_ModelViewProjectionMatrix;
+varying vec4 color;
+
+void main (void)
+{
+	const float M_PI = 3.14159265358979323846;
+	vec3 c = 2.0 * (gtf_Color.rgb - 0.5);
+	vec3 acos_c = vec3(0.0);
+	vec3 scale = vec3(1.0);
+	vec3 sign = vec3(1.0);
+
+	// pow can't handle negative numbers so take advantage of symmetry
+	if(c.r < 0.0)
+	{
+		sign.r = -1.0;
+		c.r *= -1.0;
+	}
+
+	// Taylors series expansion for acos
+	// 1000/2 iterations necessary to get the accuracy with this method
+	for(int i = 1; i < 1000; i += 2)
+	{
+		acos_c.r += scale.r * pow(c.r, float(i)) / float(i);
+		scale.r *= float(i) / float(i + 1);
+	}
+	acos_c.r = M_PI / 2.0 - sign.r * acos_c.r;
+
+	// pow can't handle negative numbers so take advantage of symmetry
+	if(c.g < 0.0)
+	{
+		sign.g = -1.0;
+		c.g *= -1.0;
+	}
+
+	// Taylors series expansion for acos
+	// 1000/2 iterations necessary to get the accuracy with this method
+	for(int i = 1; i < 1000; i += 2)
+	{
+		acos_c.g += scale.g * pow(c.g, float(i)) / float(i);
+		scale.g *= float(i) / float(i + 1);
+	}
+	acos_c.g = M_PI / 2.0 - sign.g * acos_c.g;
+
+	// pow can't handle negative numbers so take advantage of symmetry
+	if(c.b < 0.0)
+	{
+		sign.b = -1.0;
+		c.b *= -1.0;
+	}
+
+	// Taylors series expansion for acos
+	// 1000/2 iterations necessary to get the accuracy with this method
+	for(int i = 1; i < 1000; i += 2)
+	{
+		acos_c.b += scale.b * pow(c.b, float(i)) / float(i);
+		scale.b *= float(i) / float(i + 1);
+	}
+	acos_c.b = M_PI / 2.0 - sign.b * acos_c.b;
+
+	color = vec4(acos_c / M_PI, 1.0);
+	gl_Position = gtf_ModelViewProjectionMatrix * gtf_Vertex;
+}