summaryrefslogtreecommitdiff
path: root/generated_tests/builtin_function.py
blob: 7a42441570298144e9e2a0607aa120809d8215cf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
# coding=utf-8
#
# Copyright © 2011 Intel Corporation
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice (including the next
# paragraph) shall be included in all copies or substantial portions of the
# Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
# DEALINGS IN THE SOFTWARE.

# This source file defines a set of test vectors that can be used to
# test GLSL's built-in functions.  It is intended to be used by
# Python code that generates Piglit tests.
#
# The key export is the dictionary test_suite.  It contains an entry
# for each possible overload of every pure built-in function.  By
# iterating through this dictionary you can find a set of test vectors
# for testing nearly every built-in GLSL function.  Notable exceptions
# include the fragment shader functions dFdx(), dFdy(), and fwidth(),
# the texture lookup functions, and the ftransform() function, since
# they are not pure, so they can't be tested using simple test
# vectors.

import collections
import itertools
import numpy as np



# Floating point types used by Python and numpy
FLOATING_TYPES = (float, np.float64, np.float32)



class GlslBuiltinType(object):
    """Class representing a GLSL built-in type."""
    def __init__(self, name, base_type, num_cols, num_rows,
		 version_introduced):
	self.__name = name
	if base_type is not None:
	    self.__base_type = base_type
	else:
	    self.__base_type = self
	self.__num_cols = num_cols
	self.__num_rows = num_rows
	self.__version_introduced = version_introduced

    @property
    def name(self):
	"""The name of the type, as a string."""
	return self.__name

    @property
    def base_type(self):
	"""For vectors and matrices, the type of data stored in each
	element.  For scalars, equal to self.
	"""
	return self.__base_type

    @property
    def num_cols(self):
	"""For matrices, the number of columns.  For vectors and
	scalars, 1.
	"""
	return self.__num_cols

    @property
    def num_rows(self):
	"""For vectors and matrices, the number of rows.  For scalars,
	1.
	"""
	return self.__num_rows

    @property
    def is_scalar(self):
	return self.__num_cols == 1 and self.__num_rows == 1

    @property
    def is_vector(self):
	return self.__num_cols == 1 and self.__num_rows != 1

    @property
    def is_matrix(self):
	return self.__num_cols != 1

    @property
    def version_introduced(self):
	"""The earliest version of GLSL that this type appears in (as
	a string, e.g. '1.10').
	"""
	return self.__version_introduced

    def __str__(self):
	return self.__name

    def __repr__(self):
	return 'glsl_{0}'.format(self.__name)



# Concrete declarations of GlslBuiltinType
glsl_bool   = GlslBuiltinType('bool',   None,       1, 1, '1.10')
glsl_int    = GlslBuiltinType('int',    None,       1, 1, '1.10')
glsl_float  = GlslBuiltinType('float',  None,       1, 1, '1.10')
glsl_vec2   = GlslBuiltinType('vec2',   glsl_float, 1, 2, '1.10')
glsl_vec3   = GlslBuiltinType('vec3',   glsl_float, 1, 3, '1.10')
glsl_vec4   = GlslBuiltinType('vec4',   glsl_float, 1, 4, '1.10')
glsl_bvec2  = GlslBuiltinType('bvec2',  glsl_bool,  1, 2, '1.10')
glsl_bvec3  = GlslBuiltinType('bvec3',  glsl_bool,  1, 3, '1.10')
glsl_bvec4  = GlslBuiltinType('bvec4',  glsl_bool,  1, 4, '1.10')
glsl_ivec2  = GlslBuiltinType('ivec2',  glsl_int,   1, 2, '1.10')
glsl_ivec3  = GlslBuiltinType('ivec3',  glsl_int,   1, 3, '1.10')
glsl_ivec4  = GlslBuiltinType('ivec4',  glsl_int,   1, 4, '1.10')
glsl_mat2   = GlslBuiltinType('mat2',   glsl_float, 2, 2, '1.10')
glsl_mat3   = GlslBuiltinType('mat3',   glsl_float, 3, 3, '1.10')
glsl_mat4   = GlslBuiltinType('mat4',   glsl_float, 4, 4, '1.10')
glsl_mat2x2 = glsl_mat2
glsl_mat3x2 = GlslBuiltinType('mat3x2', glsl_float, 3, 2, '1.20')
glsl_mat4x2 = GlslBuiltinType('mat4x2', glsl_float, 4, 2, '1.20')
glsl_mat2x3 = GlslBuiltinType('mat2x3', glsl_float, 2, 3, '1.20')
glsl_mat3x3 = glsl_mat3
glsl_mat4x3 = GlslBuiltinType('mat4x3', glsl_float, 4, 3, '1.20')
glsl_mat2x4 = GlslBuiltinType('mat2x4', glsl_float, 2, 4, '1.20')
glsl_mat3x4 = GlslBuiltinType('mat3x4', glsl_float, 3, 4, '1.20')
glsl_mat4x4 = glsl_mat4



# Named tuple representing the signature of a single overload of a
# built-in GLSL function:
# - name is the function name.
# - version_introduced earliest version of GLSL the test applies to
#   (as a string, e.g. '1.10').
# - rettype is the return type of the function (as a GlslBuiltinType).
# - argtypes is a tuple containing the types of each function
#   parameter (as GlslBuiltinTypes).
#
# For example, the function
#
#   vec3 step(float edge, vec3 x)
#
# has a signature of
#
# Signature(name='step', version_introduced='1.10', rettype='vec3',
#           argtypes=('float', 'vec3'))
Signature = collections.namedtuple(
    'Signature', ('name', 'version_introduced', 'rettype', 'argtypes'))



# Named tuple representing a single piece of test data for testing a
# built-in GLSL function:
# - arguments is a tuple containing the arguments to apply to the
#   function.  Each argument is of a type native to numpy (e.g.
#   numpy.float32 or numpy.ndarray)
# - result is the value the function is expected to return.  It is
#   also of a type native to numpy.
# - tolerance is a float32 representing how much deviation from the
#   result we expect, considering the floating point precision
#   requirements of GLSL and OpenGL.  The value may be zero for test
#   vectors involving booleans and integers.  If result is a vector or
#   matrix, tolerance should be interpreted as the maximum permissible
#   RMS error (as would be computed by the distance() function).
TestVector = collections.namedtuple(
    'TestVector', ('arguments', 'result', 'tolerance'))



def glsl_type_of(value):
    """Return the GLSL type corresponding to the given native numpy
    value, as a GlslBuiltinType.
    """
    if isinstance(value, FLOATING_TYPES):
	return glsl_float
    elif isinstance(value, (bool, np.bool_)):
	return glsl_bool
    elif isinstance(value, (int, long)):
	return glsl_int
    else:
	assert isinstance(value, np.ndarray)
	if len(value.shape) == 1:
	    # Vector
	    vector_length = value.shape[0]
	    assert 2 <= vector_length <= 4
	    if value.dtype in FLOATING_TYPES:
		return (glsl_vec2, glsl_vec3, glsl_vec4)[vector_length - 2]
	    elif value.dtype == bool:
		return (glsl_bvec2, glsl_bvec3, glsl_bvec4)[vector_length - 2]
	    elif value.dtype == int:
		return (glsl_ivec2, glsl_ivec3, glsl_ivec4)[vector_length - 2]
	    else:
		raise Exception(
		    'Unexpected vector base type {0}'.format(value.dtype))
	else:
	    # Matrix
	    assert value.dtype in FLOATING_TYPES
	    assert len(value.shape) == 2
	    matrix_rows = value.shape[0]
	    assert 2 <= matrix_rows <= 4
	    matrix_columns = value.shape[1]
	    assert 2 <= matrix_columns <= 4
	    matrix_types = ((glsl_mat2x2, glsl_mat2x3, glsl_mat2x4),
			    (glsl_mat3x2, glsl_mat3x3, glsl_mat3x4),
			    (glsl_mat4x2, glsl_mat4x3, glsl_mat4x4))
	    return matrix_types[matrix_columns - 2][matrix_rows - 2]



def column_major_values(value):
    """Given a native numpy value, return a list of the scalar values
    comprising it, in column-major order."""
    if isinstance(value, np.ndarray):
	return list(np.reshape(value, -1, 'F'))
    else:
	return [value]



def glsl_constant(value):
    """Given a native numpy value, return GLSL code that constructs
    it."""
    column_major = np.reshape(np.array(value), -1, 'F')
    if column_major.dtype == bool:
	values = ['true' if x else 'false' for x in column_major]
    else:
	values = [repr(x) for x in column_major]
    if len(column_major) == 1:
	return values[0]
    else:
	return '{0}({1})'.format(glsl_type_of(value), ', '.join(values))



def round_to_32_bits(value):
    """If value is a floating point type, round it down to 32 bits.
    Otherwise return it unchanged.
    """
    if isinstance(value, float):
	return np.float32(value)
    elif isinstance(value, np.ndarray) and value.dtype == np.float64:
	return np.array(value, dtype=np.float32)
    else:
	return value



def extend_to_64_bits(value):
    """If value is a floating point type, extend it to 64 bits.
    Otherwise return it unchanged.
    """
    if isinstance(value, np.float32):
	return np.float64(value)
    elif isinstance(value, np.ndarray) and value.dtype == np.float32:
	return np.array(value, dtype=np.float64)
    else:
	return value



# Dictionary containing the test vectors.  Each entry in the
# dictionary represents a single overload of a single built-in
# function.  Its key is a Signature tuple, and its value is a list of
# TestVector tuples.
#
# Note: the dictionary is initialized to {} here, but it is filled
# with test vectors by code later in this file.
test_suite = {}



# Implementation
# ==============
#
# The functions below shouldn't be necessary to call from outside this
# file.  They exist solely to populate test_suite with test vectors.

# Functions that simulate GLSL built-in functions (in the cases where
# the GLSL built-in functions have no python or numpy equivalent, or
# in cases where there is a behavioral difference).  These functions
# return None if the behavior of the GLSL built-in is undefined for
# the given set of inputs.
def _arctan2(y, x):
    if x == y == 0.0:
	return None
    return np.arctan2(y, x)
def _pow(x, y):
    if x < 0.0:
	return None
    if x == 0.0 and y <= 0.0:
	return None
    return np.power(x, y)
def _exp2(x):
    # exp2() is not available in versions of numpy < 1.3.0 so we
    # emulate it with power().
    return np.power(2, x)
def _clamp(x, minVal, maxVal):
    if minVal > maxVal:
	return None
    return min(max(x, minVal), maxVal)
def _smoothstep(edge0, edge1, x):
    if edge0 >= edge1:
	return None
    t = _clamp((x-edge0)/(edge1-edge0),0.0,1.0)
    return t*t*(3.0-2.0*t)
def _normalize(x):
    return x/np.linalg.norm(x)
def _faceforward(N, I, Nref):
    if np.dot(Nref, I) < 0.0:
	return N
    else:
	return -N
def _reflect(I, N):
    return I-2*np.dot(N,I)*N
def _refract(I, N, eta):
    k = 1.0-eta*eta*(1.0-np.dot(N,I)*np.dot(N,I))
    if k < 0.0:
	return I*0.0
    else:
	return eta*I-(eta*np.dot(N,I)+np.sqrt(k))*N



def _argument_types_match(arguments, argument_indices_to_match):
    """Return True if all of the arguments indexed by
    argument_indices_to_match have the same GLSL type.
    """
    types = [glsl_type_of(arguments[i]) for i in argument_indices_to_match]
    return all(x == types[0] for x in types)



def _strict_tolerance(arguments, result):
    """Compute tolerance using a strict interpretation of the GLSL and
    OpenGL standards.

    From the GLSL 1.20 spec (4.1.4 "Floats"):

      "As an input value to one of the processing units, a
      floating-point variable is expected to match the IEEE single
      precision floating-point definition for precision and dynamic
      range.  It is not required that the precision of internal
      processing match the IEEE floating-point specification for
      floating-point operations, but the guidelines for precision
      established by the OpenGL 1.4 specification must be met."

    From the OpenGL 1.4 spec (2.1.1 "Floating-Point Computation"):

      "We require simply that numbers' floating-point parts contain
      enough bits ... so that individual results of floating-point
      operations are accurate to about 1 part in 10^5."

    A harsh interpretation of the above is that (a) no precision is
    lost in moving numbers into or out of the GPU, and (b) any
    built-in function constitutes a single operation, so therefore the
    error in applying any built-in function should be off by no more
    than 1e-5 times its theoretically correct value.

    This is not the only possible interpretation, however.  Certain
    built-in functions, such as the cross product, are computed by a
    formula consisting of many elementary multiplications and
    additions, in which a large amount of cancellation sometimes
    occurs.  It's possible that these rules are meant to apply to
    those elementary multiplications and additions, and not the full
    built-in function. Other built-in functions, such as the trig
    functions, are typically implemented by a series approximation, in
    which 1 part in 10^5 accuracy seems like overkill.  See below for
    the tolerance computation we use on these other functions.
    """
    return 1e-5 * np.linalg.norm(result)



def _trig_tolerance(arguments, result):
    """Compute a more lenient tolerance bound for trig functions.

    The GLSL and OpenGL specs don't provide any guidance as to the
    required accuracy of trig functions (other than the "1 part in
    10^5" general accuracy requirement, which seems like overkill for
    trig functions.

    So the tolerance here is rather arbitrarily chosen to be either 1
    part in 10^3 or 10^-4, whichever is larger.
    """
    return max(1e-4, 1e-3 * np.linalg.norm(result))



def _cross_product_tolerance(arguments, result):
    """Compute a more lenient tolerance bound for cross product.

    Since the computation of a cross product may involve a large
    amount of cancellation, an error tolerance of 1 part in 10^5
    (referred to the magnitude of the result vector) is overly tight.

    So instead we allow the error to be 1 part in 10^5 referred to the
    product of the magnitudes of the arguments.
    """
    assert len(arguments) == 2
    return 1e-5 * np.linalg.norm(arguments[0]) * np.linalg.norm(arguments[1])



def _simulate_function(test_inputs, python_equivalent, tolerance_function):
    """Construct test vectors by simulating a GLSL function on a list
    of possible inputs, and return a list of test vectors.

    test_inputs is a list of possible input sequences, each of which
    represents a set of arguments that should be applied to the
    function.

    python_equivalent is the function to simulate--it should return
    None if the GLSL function returns undefined results for the given
    set of inputs, otherwise it should return the expected result.
    Input sequences for which python_equivalent returns None are
    ignored.

    The function is simulated using 64 bit floats for maximum possible
    accuracy, but the output is rounded to 32 bits since that is the
    data type that we expect to get back form OpenGL.

    tolerance_function is the function to call to compute the
    tolerance.  It should take the set of arguments and the expected
    result as its parameters.  It is only used for functions that
    return floating point values.
    """
    test_vectors = []
    for inputs in test_inputs:
	expected_output = round_to_32_bits(
	    python_equivalent(*[extend_to_64_bits(x) for x in inputs]))
	if expected_output is not None:
	    if glsl_type_of(expected_output).base_type != glsl_float:
		tolerance = np.float32(0.0)
	    else:
		tolerance = np.float32(
		    tolerance_function(inputs, expected_output))
	    test_vectors.append(TestVector(inputs, expected_output, tolerance))
    return test_vectors



def _vectorize_test_vectors(test_vectors, scalar_arg_indices, vector_length):
    """Build a new set of test vectors by combining elements of
    test_vectors into vectors of length vector_length. For example,
    vectorizing the test vectors

    [TestVector((10, 20), 30, tolerance), TestVector((11, 20), 31, tolerance)]

    into vectors of length 2 would produce the result:

    [TestVector((vec2(10, 11), vec2(20, 20)), vec2(30, 31), new_tolerance)].

    Tolerances are combined in root-sum-square fashion.

    scalar_arg_indices is a sequence of argument indices which should
    not be vectorized.  So, if scalar_arg_indices is [1] in the above
    example, the result would be:

    [TestVector((vec2(10, 11), 20), vec2(30, 31), new_tolerance)].
    """
    def make_groups(test_vectors):
	"""Group test vectors according to the values passed to the
	arguments that should not be vectorized.
	"""
	groups = {}
	for tv in test_vectors:
	    key = tuple(tv.arguments[i] for i in scalar_arg_indices)
	    if key not in groups:
		groups[key] = []
	    groups[key].append(tv)
	return groups
    def partition_vectors(test_vectors, partition_size):
	"""Partition test_vectors into lists of length partition_size.
	If partition_size does not evenly divide the number of test
	vectors, wrap around as necessary to ensure that every input
	test vector is included.
	"""
	for i in xrange(0, len(test_vectors), partition_size):
	    partition = []
	    for j in xrange(partition_size):
		partition.append(test_vectors[(i + j) % len(test_vectors)])
	    yield partition
    def merge_vectors(test_vectors):
	"""Merge the given set of test vectors (whose arguments and
	result are scalars) into a single test vector whose arguments
	and result are vectors.  For argument indices in
	scalar_arg_indices, leave the argument as a scalar.
	"""
	arity = len(test_vectors[0].arguments)
	arguments = []
	for j in xrange(arity):
	    if j in scalar_arg_indices:
		arguments.append(test_vectors[0].arguments[j])
	    else:
		arguments.append(
		    np.array([tv.arguments[j] for tv in test_vectors]))
	result = np.array([tv.result for tv in test_vectors])
	tolerance = np.float32(
	    np.linalg.norm([tv.tolerance for tv in test_vectors]))
	return TestVector(arguments, result, tolerance)
    vectorized_test_vectors = []
    groups = make_groups(test_vectors)
    for key in sorted(groups.keys()):
	test_vectors = groups[key]
	vectorized_test_vectors.extend(
	    merge_vectors(partition)
	    for partition in partition_vectors(test_vectors, vector_length))
    return vectorized_test_vectors



def _store_test_vector(test_suite_dict, name, glsl_version, test_vector):
    """Store a test vector in the appropriate place in
    test_suite_dict.  The dictionary key (which is a Signature tuple)
    is generated by consulting the argument and return types of the
    test vector, and combining them with name and glsl_version.

    glsl_version is adjusted if necessary to reflect when the argument
    and return types were introduced into GLSL.
    """
    rettype = glsl_type_of(test_vector.result)
    argtypes = tuple(glsl_type_of(arg) for arg in test_vector.arguments)
    adjusted_glsl_version = max(
	glsl_version, rettype.version_introduced,
	*[t.version_introduced for t in argtypes])
    signature = Signature(name, adjusted_glsl_version, rettype, argtypes)
    if signature not in test_suite_dict:
	test_suite_dict[signature] = []
    test_suite_dict[signature].append(test_vector)



def _store_test_vectors(test_suite_dict, name, glsl_version, test_vectors):
    """Store multiple test vectors in the appropriate places in
    test_suite_dict.
    """
    for test_vector in test_vectors:
	_store_test_vector(test_suite_dict, name, glsl_version, test_vector)



def make_arguments(input_generators):
    """Construct a list of tuples of input arguments to test.

    input_generators is a list, the ith element of which is a sequence
    of values that are suitable for use as the ith argument of the
    function under test.

    Output is a list, each element of which is a tuple of arguments to
    be passed to the function under test.  These values are produced
    by taking the cartesian product of the input sequences.

    In addition, this function rounds floating point inputs to 32
    bits, so that there will be no rounding errors when the input
    values are passed into OpenGL.
    """
    input_generators = [
	[round_to_32_bits(x) for x in seq] for seq in input_generators]
    return list(itertools.product(*input_generators))



def _make_componentwise_test_vectors(test_suite_dict):
    """Add test vectors to test_suite_dict for GLSL built-in
    functions that operate on vectors in componentwise fashion.
    Examples include sin(), cos(), min(), max(), and clamp().
    """
    # Make sure atan(x) and atan(x,y) don't misbehave for very large
    # or very small input values.
    atan_inputs = [0.0]
    for exponent in (-10, -1, 0, 1, 10):
	atan_inputs.append(pow(10.0, exponent))
	atan_inputs.append(-pow(10.0, exponent))
    def f(name, arity, glsl_version, python_equivalent,
	  alternate_scalar_arg_indices, test_inputs,
	  tolerance_function = _strict_tolerance):
	"""Create test vectors for the function with the given name
	and arity, which was introduced in the given glsl_version.

	python_equivalent is a Python function which operates on scalars,
	and simulates the GLSL function.  This function should return None
	in any case where the output of the GLSL function is undefined.

	If alternate_scalar_arg_indices is not None, also create test
	vectors for an alternate vectorized version of the function,
	in which some arguments are scalars.
	alternate_scalar_arg_indices is a sequence of the indices of
	the arguments which are scalars.

	test_inputs is a list, the ith element of which is a list of
	values that are suitable for use as the ith argument of the
	function.

	If tolerance_function is supplied, it is a function which
	should be used to compute the tolerance for the test vectors.
	Otherwise, _strict_tolerance is used.
	"""
	scalar_test_vectors = _simulate_function(
	    make_arguments(test_inputs), python_equivalent, tolerance_function)
	_store_test_vectors(
	    test_suite_dict, name, glsl_version, scalar_test_vectors)
	if alternate_scalar_arg_indices is None:
	    scalar_arg_indices_list = [()]
	else:
	    scalar_arg_indices_list = [(), alternate_scalar_arg_indices]
	for scalar_arg_indices in scalar_arg_indices_list:
	    for vector_length in (2, 3, 4):
		_store_test_vectors(
		    test_suite_dict, name, glsl_version,
		    _vectorize_test_vectors(
			scalar_test_vectors, scalar_arg_indices,
			vector_length))
    f('radians', 1, '1.10', np.radians, None, [np.linspace(-180.0, 180.0, 4)])
    f('degrees', 1, '1.10', np.degrees, None, [np.linspace(-np.pi, np.pi, 4)])
    f('sin', 1, '1.10', np.sin, None, [np.linspace(-np.pi, np.pi, 4)], _trig_tolerance)
    f('cos', 1, '1.10', np.cos, None, [np.linspace(-np.pi, np.pi, 4)], _trig_tolerance)
    f('tan', 1, '1.10', np.tan, None, [np.linspace(-np.pi, np.pi, 4)], _trig_tolerance)
    f('asin', 1, '1.10', np.arcsin, None, [np.linspace(-1.0, 1.0, 4)], _trig_tolerance)
    f('acos', 1, '1.10', np.arccos, None, [np.linspace(-1.0, 1.0, 4)], _trig_tolerance)
    f('atan', 1, '1.10', np.arctan, None, [atan_inputs], _trig_tolerance)
    f('atan', 2, '1.10', _arctan2, None, [atan_inputs, atan_inputs], _trig_tolerance)
    f('pow', 2, '1.10', _pow, None, [np.linspace(0.0, 2.0, 4), np.linspace(-2.0, 2.0, 4)])
    f('exp', 1, '1.10', np.exp, None, [np.linspace(-2.0, 2.0, 4)])
    f('log', 1, '1.10', np.log, None, [np.linspace(0.01, 2.0, 4)])
    f('exp2', 1, '1.10', _exp2, None, [np.linspace(-2.0, 2.0, 4)])
    f('log2', 1, '1.10', np.log2, None, [np.linspace(0.01, 2.0, 4)])
    f('sqrt', 1, '1.10', np.sqrt, None, [np.linspace(0.0, 2.0, 4)])
    f('inversesqrt', 1, '1.10', lambda x: 1.0/np.sqrt(x), None, [np.linspace(0.1, 2.0, 4)])
    f('abs', 1, '1.10', np.abs, None, [np.linspace(-1.5, 1.5, 5)])
    f('sign', 1, '1.10', np.sign, None, [np.linspace(-1.5, 1.5, 5)])
    f('floor', 1, '1.10', np.floor, None, [np.linspace(-2.0, 2.0, 4)])
    f('ceil', 1, '1.10', np.ceil, None, [np.linspace(-2.0, 2.0, 4)])
    f('fract', 1, '1.10', lambda x: x-np.floor(x), None, [np.linspace(-2.0, 2.0, 4)])
    f('mod', 2, '1.10', lambda x, y: x-y*np.floor(x/y), [1], [np.linspace(-1.9, 1.9, 4), np.linspace(-2.0, 2.0, 4)])
    f('min', 2, '1.10', min, [1], [np.linspace(-2.0, 2.0, 4), np.linspace(-2.0, 2.0, 4)])
    f('max', 2, '1.10', max, [1], [np.linspace(-2.0, 2.0, 4), np.linspace(-2.0, 2.0, 4)])
    f('clamp', 3, '1.10', _clamp, [1, 2], [np.linspace(-2.0, 2.0, 4), np.linspace(-1.5, 1.5, 3), np.linspace(-1.5, 1.5, 3)])
    f('mix', 3, '1.10', lambda x, y, a: x*(1-a)+y*a, [2], [np.linspace(-2.0, 2.0, 2), np.linspace(-3.0, 3.0, 2), np.linspace(0.0, 1.0, 4)])
    f('step', 2, '1.10', lambda edge, x: 0.0 if x < edge else 1.0, [0], [np.linspace(-2.0, 2.0, 4), np.linspace(-2.0, 2.0, 4)])
    f('smoothstep', 3, '1.10', _smoothstep, [0, 1], [np.linspace(-1.9, 1.9, 4), np.linspace(-1.9, 1.9, 4), np.linspace(-2.0, 2.0, 4)])
_make_componentwise_test_vectors(test_suite)



def _make_vector_relational_test_vectors(test_suite_dict):
    """Add test vectors to test_suite_dict for GLSL built-in functions
    that operate on vectors of floats, ints, or bools, but not on
    single floats, ints, or bools.  Examples include lessThan(),
    equal(), and not().
    """
    _default_inputs = {
	'v': np.linspace(-1.5, 1.5, 4),
	'i': np.array([1, 2, 3, 4]),
	'b': np.array([False, True])
	}
    def f(name, arity, glsl_version, python_equivalent, arg_types,
	  tolerance_function = _strict_tolerance):
	"""Make test vectors for the function with the given name and
	arity, which was introduced in the given glsl_version.

	python_equivalent is a Python function which operates on scalars,
	and simulates the GLSL function.

	arg_types is a string containing 'v' if the function supports
	standard "vec" inputs, 'i' if it supports "ivec" inputs, and 'b'
	if it supports "bvec" inputs.  The output type of the function is
	assumed to be the same as its input type.

	If tolerance_function is supplied, it is a function which
	should be used to compute the tolerance for the test vectors.
	Otherwise, _strict_tolerance is used.
	"""
	for arg_type in arg_types:
	    test_inputs = [_default_inputs[arg_type]]*arity
	    scalar_test_vectors = _simulate_function(
		make_arguments(test_inputs), python_equivalent,
		tolerance_function)
	    for vector_length in (2, 3, 4):
		_store_test_vectors(
		    test_suite_dict, name, glsl_version,
		    _vectorize_test_vectors(
			scalar_test_vectors, (), vector_length))
    f('lessThan', 2, '1.10', lambda x, y: x < y, 'vi')
    f('lessThanEqual', 2, '1.10', lambda x, y: x <= y, 'vi')
    f('greaterThan', 2, '1.10', lambda x, y: x > y, 'vi')
    f('greaterThanEqual', 2, '1.10', lambda x, y: x >= y, 'vi')
    f('equal', 2, '1.10', lambda x, y: x == y, 'vib')
    f('not', 1, '1.10', lambda x: not x, 'b')
_make_vector_relational_test_vectors(test_suite)



def _make_vector_or_matrix_test_vectors(test_suite_dict):
    """Add test vectors to test_suite_dict for GLSL built-in functions
    that operate on vectors/matrices as a whole.  Examples include
    length(), dot(), cross(), normalize(), and refract().
    """
    _std_vectors = [
	-1.33,
	 0.85,
	 np.array([-0.10, -1.20]),
	 np.array([-0.42, 0.48]),
	 np.array([-0.03, -0.85, -0.94]),
	 np.array([1.67, 0.66, 1.87]),
	 np.array([-1.65, 1.33, 1.93, 0.76]),
	 np.array([0.80, -0.15, -0.51, 0.0])
	 ]
    _std_vectors3 = [
	np.array([-0.03, -0.85, -0.94]),
	np.array([1.67, 0.66, 1.87]),
	]
    _normalized_vectors = [_normalize(x) for x in _std_vectors]
    _nontrivial_vectors = [x for x in _std_vectors if not isinstance(x, FLOATING_TYPES)]
    _std_matrices = [
	np.array([[ 1.60,  0.76],
		  [ 1.53, -1.00]]), # mat2
	np.array([[-0.13, -0.87],
		  [-1.40,  1.40]]), # mat2
	np.array([[-1.11,  1.67, -0.41],
		  [ 0.13,  1.09, -0.02],
		  [ 0.56,  0.95,  0.24]]), # mat3
	np.array([[-1.69, -0.46, -0.18],
		  [-1.09,  1.75,  2.00],
		  [-1.53, -0.70, -1.47]]), # mat3
	np.array([[-1.00, -0.55, -1.08,  1.79],
		  [ 1.77,  0.62,  0.48, -1.35],
		  [ 0.09, -0.71, -1.39, -1.21],
		  [-0.91, -1.82, -1.43,  0.72]]), # mat4
	np.array([[ 0.06,  1.31,  1.52, -1.96],
		  [ 1.60, -0.32,  0.51, -1.84],
		  [ 1.25,  0.45,  1.90, -0.72],
		  [-0.16,  0.45, -0.88,  0.39]]), # mat4
	np.array([[ 0.09,  1.30,  1.25],
		  [-1.19,  0.08,  1.08]]), # mat3x2
	np.array([[-0.36, -1.08, -0.60],
		  [-0.53,  0.88, -1.79]]), # mat3x2
	np.array([[-0.46,  1.94],
		  [-0.45, -0.75],
		  [ 1.03, -0.50]]), # mat2x3
	np.array([[ 1.38, -1.08],
		  [-1.27,  1.83],
		  [ 1.00, -0.74]]), # mat2x3
	np.array([[ 1.81, -0.87,  0.81,  0.65],
		  [-1.16, -1.52,  0.25, -1.51]]), # mat4x2
	np.array([[ 1.93, -1.63,  0.29,  1.60],
		  [ 0.49,  0.27,  0.14,  0.94]]), # mat4x2
	np.array([[ 0.16, -1.69],
		  [-0.80,  0.59],
		  [-1.74, -1.43],
		  [-0.02, -1.21]]), # mat2x4
	np.array([[-1.02,  0.74],
		  [-1.64, -0.13],
		  [-1.59,  0.47],
		  [ 0.30,  1.13]]), # mat2x4
	np.array([[-0.27, -1.38, -1.41, -0.12],
		  [-0.17, -0.56,  1.47,  1.86],
		  [-1.85, -1.29,  1.77,  0.01]]), # mat4x3
	np.array([[-0.47, -0.15,  1.97, -1.05],
		  [-0.20,  0.53, -1.82, -1.41],
		  [-1.39, -0.19,  1.62,  1.58]]), # mat4x3
	np.array([[ 1.42, -0.86,  0.27],
		  [ 1.80, -1.74,  0.04],
		  [-1.88, -0.37,  0.43],
		  [ 1.37,  1.90,  0.71]]), # mat3x4
	np.array([[-1.72,  0.09,  0.45],
		  [-0.31, -1.58,  1.92],
		  [ 0.14,  0.18, -0.56],
		  [ 0.40, -0.77,  1.76]]), # mat3x4
	]
    _ft = [False, True]
    _bvecs = [np.array(bs) for bs in itertools.product(_ft, _ft)] + \
	[np.array(bs) for bs in itertools.product(_ft, _ft, _ft)] + \
	[np.array(bs) for bs in itertools.product(_ft, _ft, _ft, _ft)]
    def f(name, arity, glsl_version, python_equivalent,
	  argument_indices_to_match, test_inputs,
	  tolerance_function = _strict_tolerance):
	"""Make test vectors for the function with the given name and
	arity, which was introduced in the given glsl_version.

	python_equivalent is a Python function which simulates the GLSL
	function.  This function should return None in any case where the
	output of the GLSL function is undefined.  However, it need not
	check that the lengths of the input vectors are all the same.

	If argument_indices_to_match is not None, it is a sequence of
	argument indices indicating which arguments of the function
	need to have matching types.

	test_inputs is a list, the ith element of which is a list of
	vectors and/or scalars that are suitable for use as the ith
	argument of the function.

	If tolerance_function is supplied, it is a function which
	should be used to compute the tolerance for the test vectors.
	Otherwise, _strict_tolerance is used.
	"""
	test_inputs = make_arguments(test_inputs)
	if argument_indices_to_match is not None:
	    test_inputs = [
		arguments
		for arguments in test_inputs
		if _argument_types_match(arguments, argument_indices_to_match)]
	_store_test_vectors(
	    test_suite_dict, name, glsl_version,
	    _simulate_function(
		test_inputs, python_equivalent, tolerance_function))
    f('length', 1, '1.10', np.linalg.norm, None, [_std_vectors])
    f('distance', 2, '1.10', lambda x, y: np.linalg.norm(x-y), [0, 1], [_std_vectors, _std_vectors])
    f('dot', 2, '1.10', np.dot, [0, 1], [_std_vectors, _std_vectors])
    f('cross', 2, '1.10', np.cross, [0, 1], [_std_vectors3, _std_vectors3], _cross_product_tolerance)
    f('normalize', 1, '1.10', _normalize, None, [_std_vectors])
    f('faceforward', 3, '1.10', _faceforward, [0, 1, 2], [_std_vectors, _std_vectors, _std_vectors])
    f('reflect', 2, '1.10', _reflect, [0, 1], [_std_vectors, _normalized_vectors])
    f('refract', 3, '1.10', _refract, [0, 1], [_normalized_vectors, _normalized_vectors, [0.5, 2.0]])

    # Note: technically matrixCompMult operates componentwise.
    # However, since it is the only componentwise function to operate
    # on matrices, it is easier to generate test cases for it here
    # than to add matrix support to _make_componentwise_test_vectors.
    f('matrixCompMult', 2, '1.10', lambda x, y: x*y, [0, 1], [_std_matrices, _std_matrices])

    f('outerProduct', 2, '1.20', np.outer, None, [_nontrivial_vectors, _nontrivial_vectors])
    f('transpose', 1, '1.20', np.transpose, None, [_std_matrices])
    f('any', 1, '1.10', any, None, [_bvecs])
    f('all', 1, '1.10', all, None, [_bvecs])
_make_vector_or_matrix_test_vectors(test_suite)