Reimplement image input handling for toktx. (#702)

* Add imageio library.
* Rework toktx to use the imageio library and break up the
   gigantic main loop.
* Add git subrepo of {fmt} library 9.1.0 used by imageio
* Remove VS2017 builds from CI as fmt needs a more recent version.

The output plugins are empty shells.

All toktx tests pass. Some golden images are modified due to
toktx now doing a transfer function conversion from BT709
to sRGB when reading npbm files. Some tests are modified because
toktx no longer chooses sRGB or Linear when the gamma is
somewhere between them.

fmt was previously added to another branch via PR #662.

* Adopt fmt 9.1.0 for formatting (#662)

* git subrepo clone --branch=9.1.0 https://github.com/fmtlib/fmt.git other_projects/fmt

subrepo:
  subdir:   "other_projects/fmt"
  merged:   "a3370119"
upstream:
  origin:   "https://github.com/fmtlib/fmt.git"
  branch:   "9.1.0"
  commit:   "a3370119"
git-subrepo:
  version:  "0.4.5"
  origin:   "https://github.com/ingydotnet/git-subrepo"
  commit:   "dbb99be"

The parent in other_projects/fmt/.gitrepo has been updated to account for this current PR.


Co-authored-by: Császár Mátyás <VaderY@users.noreply.github.com>

.reuse/dep5

@@ -103,7 +103,7 @@ Files: lib/basisu/basisu_astc_decomp.*
 Copyright: 2016 The Android Open Source Project
 License: Apache-2.0
 
-Files: tools/toktx/lodepng.*
+Files: tools/imageio/png.imageio/lodepng.*
 Copyright: 2005-2019 Lode Vandevenne
 License: Zlib
 
@@ -200,3 +200,7 @@ License: MIT
 Files: the_khronos_group_inc.p12.enc
 Copyright: 2022 The Khronos Group Inc.
 License: Apache-2.0
+
+Files: other_projects/fmt/*
+Copyright: 2012 - present Victor Zverovich
+License: MIT

CMakeLists.txt

@@ -923,6 +923,9 @@ else()
     target_link_libraries(ktx PRIVATE ${ASTC_LIB_TARGET})
 endif()
 
+# FMT
+add_subdirectory(other_projects/fmt)
+
 # Tools
 if(KTX_FEATURE_TOOLS)
     add_subdirectory(tools)

other_projects/fmt/.clang-format

@@ -0,0 +1,8 @@
+# Run manually to reformat a file:
+# clang-format -i --style=file <file>
+Language: Cpp
+BasedOnStyle: Google
+IndentPPDirectives: AfterHash
+IndentCaseLabels: false
+AlwaysBreakTemplateDeclarations: false
+DerivePointerAlignment: false

other_projects/fmt/.github/issue_template.md

@@ -0,0 +1,6 @@
+<!--
+Please make sure that the problem reproduces on the current master before
+submitting an issue.
+If possible please provide a repro on Compiler Explorer:
+https://godbolt.org/z/fxccbh53W.
+-->

other_projects/fmt/.github/pull_request_template.md

@@ -0,0 +1,6 @@
+<!--
+Please read the contribution guidelines before submitting a pull request:
+https://github.com/fmtlib/fmt/blob/master/CONTRIBUTING.md.
+By submitting this pull request, you agree that your contributions are licensed
+under the {fmt} license, and agree to future changes to the licensing.
+-->

other_projects/fmt/.github/workflows/doc.yml

@@ -0,0 +1,27 @@
+name: doc
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    # Use Ubuntu 20.04 because doxygen 1.8.13 from Ubuntu 18.04 is broken.
+    runs-on: ubuntu-20.04
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Create Build Environment
+      run: |
+        sudo apt update
+        sudo apt install doxygen python3-virtualenv
+        sudo npm install -g less clean-css
+        cmake -E make_directory ${{runner.workspace}}/build
+
+    - name: Build
+      working-directory: ${{runner.workspace}}/build
+      env:
+        KEY: ${{secrets.KEY}}
+      run: $GITHUB_WORKSPACE/support/build-docs.py

other_projects/fmt/.github/workflows/linux.yml

@@ -0,0 +1,94 @@
+name: linux
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        cxx: [g++-4.8, g++-10, clang++-9]
+        build_type: [Debug, Release]
+        std: [11]
+        os: [ubuntu-18.04]
+        include:
+          - cxx: g++-4.8
+            install: sudo apt install g++-4.8
+            os: ubuntu-18.04
+          - cxx: g++-8
+            build_type: Debug
+            std: 14
+            install: sudo apt install g++-8
+            os: ubuntu-18.04
+          - cxx: g++-8
+            build_type: Debug
+            std: 17
+            install: sudo apt install g++-8
+            os: ubuntu-18.04
+          - cxx: g++-10
+            build_type: Debug
+            std: 17
+            os: ubuntu-18.04
+          - cxx: g++-11
+            build_type: Debug
+            std: 20
+            os: ubuntu-20.04
+            install: sudo apt install g++-11
+          - cxx: clang++-8
+            build_type: Debug
+            std: 17
+            cxxflags: -stdlib=libc++
+            os: ubuntu-18.04
+            install: sudo apt install clang-8 libc++-8-dev libc++abi-8-dev
+          - cxx: clang++-9
+            build_type: Debug
+            fuzz: -DFMT_FUZZ=ON -DFMT_FUZZ_LINKMAIN=ON
+            std: 17
+            os: ubuntu-18.04
+          - cxx: clang++-11
+            build_type: Debug
+            std: 20
+            os: ubuntu-20.04
+          - cxx: clang++-11
+            build_type: Debug
+            std: 20
+            cxxflags: -stdlib=libc++
+            os: ubuntu-20.04
+            install: sudo apt install libc++-11-dev libc++abi-11-dev
+          - shared: -DBUILD_SHARED_LIBS=ON
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Create Build Environment
+      run: |
+        ${{matrix.install}}
+        sudo apt update
+        sudo apt install locales-all
+        cmake -E make_directory ${{runner.workspace}}/build
+
+    - name: Configure
+      working-directory: ${{runner.workspace}}/build
+      env:
+        CXX: ${{matrix.cxx}}
+        CXXFLAGS: ${{matrix.cxxflags}}
+      run: |
+        cmake -DCMAKE_BUILD_TYPE=${{matrix.build_type}} ${{matrix.fuzz}} ${{matrix.shared}} \
+              -DCMAKE_CXX_STANDARD=${{matrix.std}} -DFMT_DOC=OFF \
+              -DCMAKE_CXX_VISIBILITY_PRESET=hidden -DCMAKE_VISIBILITY_INLINES_HIDDEN=ON \
+              -DFMT_PEDANTIC=ON -DFMT_WERROR=ON $GITHUB_WORKSPACE
+
+    - name: Build
+      working-directory: ${{runner.workspace}}/build
+      run: |
+        threads=`nproc`
+        cmake --build . --config ${{matrix.build_type}} --parallel $threads
+
+    - name: Test
+      working-directory: ${{runner.workspace}}/build
+      run: ctest -C ${{matrix.build_type}}
+      env:
+        CTEST_OUTPUT_ON_FAILURE: True