1-------------------------------------------------------------------------
2drawElements Quality Program Test Specification
3-----------------------------------------------
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    Title
20
21Tests:
22 + dEQP-GLES31.functional.fbo.no_attachments.*
23 + dEQP-GLES31.functional.fbo.completeness.no_attachments
24
25Includes:
26 + Framebuffer completeness
27 + Rendering
28   - Multiple sizes
29   - Multisampled
30 + Limits
31
32Excludes:
33 + Most usefull forms of output
34   - Atomic counter use (none guaranteed in fragment shader)
35   - Image read/write (no image units guaranteed in fragment shader)
36 + Fixed sample locations (no way to verify)
37
38Description:
39
40Framebuffer completenss is tested trivially
41
42Rendering is verified to happen with occlusion queries. This rather limited
43method has been chosen since there is a general shortage of guaranteed valid
44ways of outputting data from a fragment shader without a color/depth/stencil
45buffer. Namely all relevant minimum maximums (atomic counters, atomic counter
46buffers, shader storage blocks and image uniforms) are zero.
47
48Basic functioning of the framebuffer is tested by rendering a full buffer quad
49and verifying its presence with an occlusion query. Size of the framebuffer
50is verified by running a shader that discard all fragments that are not within
51a given pixel's boundaries with several pixels placed around the edge of the
52framebuffer and checking for that these fragments were (not) rendered with
53an occlusion query. Each tested pixel has its own render call and occlusion
54query.
55
56Basic functionality tests iterate a number of size & sampling parameters,
57including the required maximum and implementation reported limits
58
59The completeness test verifies that a framebuffer with both widht and height
60set is considered complete.
61