Compositor: Unify references between CPU and GPU tests

This patch removes the references for the GPU tests and uses the CPU
references for both CPU and GPU, since they are expected to match. This
also unifies the tests scripts into a single script with an argument
for execution device.

tests/python/compositor_render_tests.py

@@ -0,0 +1,80 @@
+#!/usr/bin/env python3
+# SPDX-FileCopyrightText: 2015-2022 Blender Authors
+#
+# SPDX-License-Identifier: Apache-2.0
+
+import argparse
+import os
+import sys
+
+
+# When run from inside Blender, render and exit.
+try:
+    import bpy
+    inside_blender = True
+except ImportError:
+    inside_blender = False
+
+
+def get_compositor_device_setter_script(execution_device):
+    return f"import bpy; bpy.data.scenes[0].render.compositor_device = '{execution_device}'"
+
+
+def get_arguments(filepath, output_filepath, execution_device):
+    return [
+        "--background",
+        "--factory-startup",
+        "--enable-autoexec",
+        "--debug-memory",
+        "--debug-exit-on-error",
+        filepath,
+        "-P", os.path.realpath(__file__),
+        "--python-expr", get_compositor_device_setter_script(execution_device),
+        "-o", output_filepath,
+        "-F", "PNG",
+        "-f", "1"]
+
+
+def create_argparse():
+    parser = argparse.ArgumentParser(
+        description="Run test script for each blend file in TESTDIR, comparing the render result with known output."
+    )
+    parser.add_argument("--blender", required=True)
+    parser.add_argument("--testdir", required=True)
+    parser.add_argument("--outdir", required=True)
+    parser.add_argument("--oiiotool", required=True)
+    parser.add_argument("--gpu", default=False, action='store_true')
+    parser.add_argument('--batch', default=False, action='store_true')
+    return parser
+
+
+def main():
+    parser = create_argparse()
+    args = parser.parse_args()
+
+    from modules import render_report
+    execution_device = "GPU" if args.gpu else "CPU"
+    report_title = f"Compositor {execution_device}"
+    report = render_report.Report(report_title, args.outdir, args.oiiotool)
+    report.set_pixelated(True)
+    report.set_reference_dir("compositor_renders")
+
+    if os.path.basename(args.testdir) == 'filter':
+        # Temporary change to pass OpenImageDenoise test with both 1.3 and 1.4.
+        report.set_fail_threshold(0.05)
+    elif os.path.basename(args.testdir) == 'matte':
+        # The node_keying_matte.blend test is very sensitive to the exact values in the
+        # input image. It makes it hard to precisely match results on different systems
+        # (with and without SSE, i.e.), especially when OCIO has different precision for
+        # the exponent transform on different platforms.
+        report.set_fail_threshold(0.06)
+        report.set_fail_percent(2)
+
+    arguments_callback = lambda filepath, output_filepath: get_arguments(filepath, output_filepath, execution_device)
+    ok = report.run(args.testdir, args.blender, arguments_callback, batch=args.batch)
+
+    sys.exit(not ok)
+
+
+if not inside_blender and __name__ == "__main__":
+    main()