1-------------------------------------------------------------------------
2drawElements Quality Program Test Specification
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4
5Copyright 2014 The Android Open Source Project
6
7Licensed under the Apache License, Version 2.0 (the "License");
8you may not use this file except in compliance with the License.
9You may obtain a copy of the License at
10
11     http://www.apache.org/licenses/LICENSE-2.0
12
13Unless required by applicable law or agreed to in writing, software
14distributed under the License is distributed on an "AS IS" BASIS,
15WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16See the License for the specific language governing permissions and
17limitations under the License.
18-------------------------------------------------------------------------
19    Geometry and tessellation shader interaction tests
20
21Tests:
22 + dEQP-GLES31.functional.tessellation_geometry_interaction.*
23 + dEQP-GLES31.stress.tessellation_geometry_interaction.*
24
25Includes:
26 + Basic render tests using a shader program with tessellation and
27   geometry shading stages.
28 + Render tests with maximum geometry amplification in different stages
29 + Scattering render tests where result primitives are scattered all
30   over the viewport and render layers.
31 + Basic transform feedback tests
32 + Point size render tests
33
34Excludes:
35 + Complex rendering tests
36 + SSBO memory access ordering test between tessellation and geometry shaders
37 + Transform feedback with all basic types
38
39Description:
40
41render.passthrough cases tests basic rendering with a shader program with
42attached tessellation and geometry shaders. Tests verify that attaching either a
43passthrough geometry or tessellation shader does not change the result image. In
44*_passthrough_geometry_* cases, the pattern is first rendered without a geometry
45shader and then with a passthrough geometry shader. In
46*_passthrough_tessellation_* cases, image is first rendered without a
47tessellation stage and then with a passthrough tessellation shader attached.
48
49render.limits.* cases test rendering with a five stage shader program with a
50shader that uses the maximum number of geometry output vertices, uses maximum
51number geometry shader instances, or sets the maximum tessellation level.
52*_required_* cases use the maximum limit as required by the extension
53specifications and *_implementation_* cases use the maximum limit reported by
54the glGetInteger(GL_MAX_...) queries. Cases render a grid of green and yellow
55cells, and the result image is verified.
56
57The
58dEQP-GLES31.stress.tessellation_geometry_interaction.render_multiple_limits.*
59cases are otherwise identical to the functional cases but the stress.*
60counterparts test multiple implementation and specification mandated limits at
61the same time. Due to the extreme geometry amplification in certain tests, the
62OUT_OF_MEMORY error is treated as a valid result (in addition to the valid
63render result).
64
65render.scatter.* cases use geometry shader to scatter the output primitives all
66over the viewport. In the geometry_scatter_instances case, each geometry shader
67instance emits its primitives near to each other but far form the primitives
68emitted by the other instances of the same geometry shader execution. In the
69geometry_scatter_primitives, each geometry shader instance emits its primitives
70far form each other. In geometry_scatter_layers case, each emitted primitive of
71a geometry shader instance is assigned a different layer index. Cases render a
72grid of green and yellow cells, and the result image is verified.
73
74feedback.tessellation_output_*_geometry_output_* cases test that transform
75feedback works with five stage shader programs with different tessellation and
76geometry output primitive types. Tests verify the validity of feedback results
77and the value GL_PRIMITIVES_GENERATED query and then compare the rendered image
78against the feedback results.
79
80feedback.record_variable_selection case tests that when using transform
81feedback the recorded variable is selected from the geometry shader if the
82geometry shader is active.
83
84point_size.* cases test reading and writing to gl_PointSize varible in different
85shader stages. In {vertex, control, evaluation, geometry}_set cases, a constant
86is assigned to the gl_PointSize in the corresponding shader stage. In {vertex,
87control, ...}_add cases, gl_PointSize is incremented by a constant. In {eval,
88default}_default cases, the corresponding shader stage is active, but it does
89not modify the point size or use the shader stage specific point size extension.
90The shader program is used to render a single point, and the rendered point size
91is then verified from the image.
92