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Diffstat (limited to '')
-rw-r--r-- | dom/canvas/test/webgl-conf/checkout/conformance/ogles/GL/atan/atan_vec2_frag_xvaryyvary_ref.frag | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/dom/canvas/test/webgl-conf/checkout/conformance/ogles/GL/atan/atan_vec2_frag_xvaryyvary_ref.frag b/dom/canvas/test/webgl-conf/checkout/conformance/ogles/GL/atan/atan_vec2_frag_xvaryyvary_ref.frag new file mode 100644 index 0000000000..bfd7117d48 --- /dev/null +++ b/dom/canvas/test/webgl-conf/checkout/conformance/ogles/GL/atan/atan_vec2_frag_xvaryyvary_ref.frag @@ -0,0 +1,133 @@ + +/* +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; + vec2 x = 2.0 * (color.gg - 0.5); + vec2 y = 2.0 * (color.bb - 0.5); + vec2 c; + vec2 atan_c = vec2(0.0); + vec2 scale = vec2(1.0); + vec2 sign = vec2(1.0); + vec4 result = vec4(0.0, 0.0, 0.0, 1.0); + const float epsilon = 1.0e-4; + + // Avoid evaluating atan(0, x) for x < epsilon because it's implementation-dependent + if(x[0] > epsilon || abs(y[0]) > epsilon) + { + if(x[0] < 0.0 ^^ y[0] < 0.0) + { + sign[0] = -1.0; + } + + if(abs(y[0]) <= abs(x[0])) + { + c[0] = abs(y[0] / x[0]); + // Taylors series expansion for atan + atan_c[0] += scale[0] * pow(c[0], float(1)) / float(1); + scale[0] *= -1.0; + atan_c[0] += scale[0] * pow(c[0], float(3)) / float(3); + scale[0] *= -1.0; + atan_c[0] += scale[0] * pow(c[0], float(5)) / float(5); + scale[0] *= -1.0; + atan_c[0] += scale[0] * pow(c[0], float(7)) / float(7); + scale[0] *= -1.0; + atan_c[0] += scale[0] * pow(c[0], float(9)) / float(9); + scale[0] *= -1.0; + atan_c[0] += scale[0] * pow(c[0], float(11)) / float(11); + scale[0] *= -1.0; + + result[0] = sign[0] * atan_c[0] / (2.0 * M_PI) + 0.5; + } + else + { + c[0] = abs(x[0] / y[0]); + + // Taylors series expansion for atan + atan_c[0] += scale[0] * pow(c[0], float(1)) / float(1); + scale[0] *= -1.0; + atan_c[0] += scale[0] * pow(c[0], float(3)) / float(3); + scale[0] *= -1.0; + atan_c[0] += scale[0] * pow(c[0], float(5)) / float(5); + scale[0] *= -1.0; + atan_c[0] += scale[0] * pow(c[0], float(7)) / float(7); + scale[0] *= -1.0; + atan_c[0] += scale[0] * pow(c[0], float(9)) / float(9); + scale[0] *= -1.0; + atan_c[0] += scale[0] * pow(c[0], float(11)) / float(11); + scale[0] *= -1.0; + + result[0] = sign[0] * (M_PI / 2.0 - atan_c[0]) / (2.0 * M_PI) + 0.5; + } + + if(x[0] < 0.0) + if(y[0] < 0.0) result[0] -= 0.5; + else if(y[0] > 0.0) result[0] += 0.5; + } + + if(x[1] > epsilon || abs(y[1]) > epsilon) + { + + if(x[1] < 0.0 ^^ y[1] < 0.0) + { + sign[1] = -1.0; + } + + if(abs(y[1]) <= abs(x[1])) + { + c[1] = abs(y[1] / x[1]); + // Taylors series expansion for atan + atan_c[1] += scale[1] * pow(c[1], float(1)) / float(1); + scale[1] *= -1.0; + atan_c[1] += scale[1] * pow(c[1], float(3)) / float(3); + scale[1] *= -1.0; + atan_c[1] += scale[1] * pow(c[1], float(5)) / float(5); + scale[1] *= -1.0; + atan_c[1] += scale[1] * pow(c[1], float(7)) / float(7); + scale[1] *= -1.0; + atan_c[1] += scale[1] * pow(c[1], float(9)) / float(9); + scale[1] *= -1.0; + atan_c[1] += scale[1] * pow(c[1], float(11)) / float(11); + scale[1] *= -1.0; + + result[1] = sign[1] * atan_c[1] / (2.0 * M_PI) + 0.5; + } + else + { + c[1] = abs(x[1] / y[1]); + + // Taylors series expansion for atan + atan_c[1] += scale[1] * pow(c[1], float(1)) / float(1); + scale[1] *= -1.0; + atan_c[1] += scale[1] * pow(c[1], float(3)) / float(3); + scale[1] *= -1.0; + atan_c[1] += scale[1] * pow(c[1], float(5)) / float(5); + scale[1] *= -1.0; + atan_c[1] += scale[1] * pow(c[1], float(7)) / float(7); + scale[1] *= -1.0; + atan_c[1] += scale[1] * pow(c[1], float(9)) / float(9); + scale[1] *= -1.0; + atan_c[1] += scale[1] * pow(c[1], float(11)) / float(11); + scale[1] *= -1.0; + + result[1] = sign[1] * (M_PI / 2.0 - atan_c[1]) / (2.0 * M_PI) + 0.5; + } + + if(x[1] < 0.0) + if(y[1] < 0.0) result[1] -= 0.5; + else if(y[1] > 0.0) result[1] += 0.5; + } + + gl_FragColor = result; +} |