| ------------------------------------------------------------------------- |
| drawElements Quality Program Test Specification |
| ----------------------------------------------- |
| |
| Copyright 2014 The Android Open Source Project |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| ------------------------------------------------------------------------- |
| Mipmapping tests |
| |
| Tests: |
| + dEQP-GLES3.functional.texture.mipmap.* |
| |
| Includes: |
| + All mipmap filtering modes |
| + Lod computation verification |
| + Affine and projected transforms |
| + User-supplied bias to texture lookup |
| + Lod controls: min and max lod |
| + 2D and cube map textures |
| |
| Excludes: |
| + Only selected texture formats are exercised |
| |
| Description: |
| |
| Mipmapping tests render a pre-defined grid of quads. For 2D textures regular |
| 4x4 grid layout is used. For cube map textures the viewport is recursively |
| subdivided into smaller areas and each is filled with samples from single |
| cube face. |
| |
| Each texture level is filled with single color. However, each mipmap level |
| gets assigned a different color from a continuous gradient. Thus it is possible |
| to evaluate how accurately the lod was computed by inspecting the resulting |
| colorbuffer. |
| |
| OpenGL ES specification allows approximating both derivate- and lod computation. |
| Thus two reference images are rendered: one rendered according to the minimum |
| bound for the approximation and another based on the maximum bound. The rendered |
| pixels must be in between the two bounds in order to be valid. In order to |
| compensate the derivate approximation the pixels are actually checked against |
| a 3x3 neighbor around the pixel. |
