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tools/skpdiff/generate_pmetric_tables.py

Index: tools/skpdiff/generate_pmetric_tables.py
diff --git a/tools/skpdiff/generate_pmetric_tables.py b/tools/skpdiff/generate_pmetric_tables.py
deleted file mode 100755
index 71c9114c06d0afd1f9f5b93ff0ff680fa1535cc5..0000000000000000000000000000000000000000
--- a/tools/skpdiff/generate_pmetric_tables.py
+++ /dev/null
@@ -1,149 +0,0 @@
-#!/usr/bin/python
-# -*- coding: utf-8 -*-
-
-from __future__ import print_function
-from math import *
-
-
-COPYRIGHT = '''/*
- * Copyright 2013 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */'''
-
-
-HELP = '// To regenerate SkPMetricUtil_generated.h, simply run ./generate_pmetric_tables.py'
-
-
-# From Barten SPIE 1989
-def contrast_sensitivity(cycles_per_degree, luminance):
-    a = 440.0 * pow(1.0 + 0.7 / luminance, -0.2)
-    b = 0.3 * pow(1 + 100.0 / luminance, 0.15)
-    return a * cycles_per_degree * exp(-b * cycles_per_degree) * sqrt(1.0 + 0.06 * exp(b * cycles_per_degree))
-
-
-# From Ward Larson Siggraph 1997
-def threshold_vs_intensity(adaptation_luminance):
-    log_lum = float('-inf') # Works in Python 2.6+
-    try:
-        log_lum = log10(adaptation_luminance)
-    except ValueError:
-        pass
-
-    x = 0.0
-
-    if log_lum < -3.94:
-        x = -2.86
-
-    elif log_lum < -1.44:
-        x = pow(0.405 * log_lum + 1.6, 2.18) - 2.86
-
-    elif log_lum < -0.0184:
-        x = log_lum - 0.395
-
-    elif log_lum < 1.9:
-        x = pow(0.249 * log_lum + 0.65, 2.7) - 0.72
-
-    else:
-        x = log_lum - 1.255
-
-    return pow(10.0, x)
-
-
-# From Daly 1993
-def visual_mask(contrast):
-    x = pow(392.498 * contrast, 0.7)
-    x = pow(0.0153 * x, 4.0)
-    return pow(1.0 + x, 0.25)
-
-
-# float gCubeRootTable[]
-CUBE_ROOT_ACCESS_FUNCTION = '''
-static float get_cube_root(float value) {
-    SkASSERT(value >= 0.0f);
-    SkASSERT(value * 1023.0f < 1024.0f);
-    return gCubeRootTable[(int)(value * 1023.0f)];
-}
-'''
-def generate_cube_root_table(stream):
-    print('static float gCubeRootTable[] = {', end='', file=stream)
-    for i in range(1024):
-        if i % 6 == 0:
-            print('\n    ', end='', file=stream)
-        print("%.10f" % pow(i / 1024.0, 1.0 / 3.0), end='f,', file=stream)
-    print('\n};', end='', file=stream)
-    print(CUBE_ROOT_ACCESS_FUNCTION, file=stream)
-
-
-# float gGammaTable[]
-GAMMA_ACCESS_FUNCTION = '''
-static float get_gamma(unsigned char value) {
-    return gGammaTable[value];
-}
-'''
-def generate_gamma_table(stream):
-    print('static float gGammaTable[] = {', end='', file=stream)
-    for i in range(256):
-        if i % 6 == 0:
-            print('\n    ', end='', file=stream)
-        print("%.10f" % pow(i / 255.0, 2.2), end='f,', file=stream)
-    print('\n};', end='', file=stream)
-    print(GAMMA_ACCESS_FUNCTION, file=stream)
-
-
-# float gTVITable[]
-TVI_ACCESS_FUNCTION = '''
-static float get_threshold_vs_intensity(float value) {
-    SkASSERT(value >= 0.0f);
-    SkASSERT(value < 100.0f);
-    return gTVITable[(int)(value * 100.0f)];
-}
-'''
-def generate_tvi_table(stream):
-    print('static float gTVITable[] = {', end='', file=stream)
-    for i in range(10000):
-        if i % 6 == 0:
-            print('\n    ', end='', file=stream)
-        print("%.10f" % threshold_vs_intensity(i / 100.0), end='f,', file=stream)
-    print('\n};', end='', file=stream)
-    print(TVI_ACCESS_FUNCTION, file=stream)
-
-
-# float gVisualMaskTable[]
-VISUAL_MASK_DOMAIN = 4000
-VISUAL_MASK_ACCESS_FUNCTION = '''
-static float get_visual_mask(float value) {{
-    SkASSERT(value >= 0.0f);
-    SkASSERT(value < {}.0f);
-    return gVisualMaskTable[(int)value];
-}}'''
-def generate_visual_mask_table(stream):
-    print('static float gVisualMaskTable[] = {', end='', file=stream)
-    for i in range(VISUAL_MASK_DOMAIN):
-        if i % 6 == 0:
-            print('\n    ', end='', file=stream)
-        print("%.10f" % visual_mask(i), end='f,', file=stream)
-    print('\n};', end='', file=stream)
-    print(VISUAL_MASK_ACCESS_FUNCTION.format(VISUAL_MASK_DOMAIN), file=stream)
-
-
-def generate_lookup_tables(stream):
-    print(COPYRIGHT, file=stream)
-    print(HELP, file=stream)
-    print('namespace SkPMetricUtil {', file=stream)
-    generate_cube_root_table(stream)
-    generate_gamma_table(stream)
-    generate_tvi_table(stream)
-    generate_visual_mask_table(stream)
-    print('}', file=stream)
-
-
-def main():
-    pmetric_util_out = open('SkPMetricUtil_generated.h', 'wb')
-    generate_lookup_tables(pmetric_util_out)
-    pmetric_util_out.close()
-
-
-if __name__ == '__main__':
-    main()