SkQP: make_gmkb, gm_knowledge (GM Knowledgebase)

Add a real implementation for gm_knowledge.h  This depends on
the presence of files in the form $GMK_DIR/foo/{max,min}.png

The implementation also writes out failures in a report directory.

Add a utility: experimental/make_gmkb which is a stand-alone
go executable that generates the foo/{max,min}.png data.

tools/skqp/README.md has instructions on running SkQP.

Also: add SkFontMgrPriv.h

Change-Id: Ibe1e9a7e7de143d14eee3877f5f2d2d8713f7f49
Reviewed-on: https://skia-review.googlesource.com/65380
Reviewed-by: Yuqian Li <liyuqian@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>

1 files changed, 66 insertions, 0 deletions

diff --git a/tools/skqp/README.md b/tools/skqp/README.md
new file mode 100644
index 0000000000..beac911ba0
--- /dev/null
+++ b/tools/skqp/README.md
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+
+SkQP
+====
+
+**Motivation**: Test an Android device’s GPU and OpenGLES & Vulkan drivers with
+Skia and Skia’s existing unit & rendering tests.
+
+How To Use SkQP on your Android device:
+
+1.  To build SkQP you need to install the
+    [Android NDK](https://developer.android.com/ndk/).
+
+2.  Checkout Skia, then go to the source directory:
+
+        cd $SKIA_SOURCE_DIRECTORY
+
+3.  Configure and build Skia for your device's architecture:
+
+        arch='arm64'  # Also valid: 'arm', 'x68', 'x64'
+        android_ndk="${HOME}/ndk"  # Or wherever you installed the NDK.
+        mkdir -p out/${arch}-rel
+        cat > out/${arch}-rel/args.gn << EOF
+            ndk = "$android_ndk"
+            ndk_api = 24
+            target_cpu = "$arch"
+            skia_embed_resources = true
+            is_debug = false
+        EOF
+        tools/git-sync-deps
+        bin/gn gen out/${arch}-rel
+        ninja -C out/${arch}-rel skqp_lib
+
+4.  Download meta.json from [https://goo.gl/jBw3Dd](https://goo.gl/jBw3Dd) .
+    This is the data used to build the validation model.
+
+5.  Generate the validation model data:
+
+        rm -rf platform_tools/android/apps/skqp/src/main/assets/gmkb
+        go get go.skia.org/infra/golden/go/search
+        go run tools/skqp/make_gmkb.go ~/Downloads/meta.json \
+            platform_tools/android/apps/skqp/src/main/assets/gmkb
+
+Run as an executable
+--------------------
+
+1.  Build the SkQP program, load files on the device, and run skqp:
+
+        ninja -C out/${arch}-rel skqp
+        adb shell "cd /data/local/tmp; rm -rf gmkb report"
+        adb push platform_tools/android/apps/skqp/src/main/assets/gmkb \
+            /data/local/tmp/
+        adb push out/${arch}-rel/skqp /data/local/tmp/
+        adb shell "cd /data/local/tmp; ./skqp gmkb report"
+
+2.  Produce a one-page error report if there are errors:
+
+        rm -rf /tmp/report
+        if adb shell test -d /data/local/tmp/report; then
+            adb pull /data/local/tmp/report /tmp/
+            tools/skqp/make_report.py /tmp/report
+        fi
+
+Run as an APK
+-------------
+
+[TODO]