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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.
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19    Depth test
20
21Tests:
22 + dEQP-GLES2.functional.depth.*
23
24Includes:
25 + Depth buffer update when rendering triangles with GL_ALWAYS
26 + Depth test when rendering triangles
27 + All depth comparison functions
28
29Excludes:
30 + Lines and points
31 + Depth mask
32 + glPolygonOffset()
33 + Overlapping primitives in single draw call
34 + Interaction with stencil test
35
36Description:
37
38Each test case renders 4 pairs of quads, arranged in a 2x2 grid. First
39quad is rendered with GL_ALWAYS depth test mode, while the second uses
40the depth test mode stated in test case name. First pair of quads have
41exactly same z, in the second pair z1 < z2 and in the third pair z2 < z1.
42In the fourth pair z1 = 0 and z2 is interpolated between -1.0 and 1.0,
43e.g. the quads are intersecting.
44
45The first quad in each pair is red, while the second one is green.
46The resulting image depends on the depth test mode used when rendering
47the second quads.
48
49Test results are verified by comparing the rendered image against a
50reference image. The reference is rendered using a simplified model
51of the GL rendering pipe.
52