Add shaders re-implemented in HLSL

These were written against the shaders at revision eddd724e7.
There have been changes made since then, which will need to be mirrored.

See `data/hlsl/README.md` for the current status of each sample.

data/hlsl/compile.py

@@ -0,0 +1,73 @@
+# Copyright 2020 Google LLC
+
+import argparse
+import fileinput
+import os
+import subprocess
+import sys
+
+parser = argparse.ArgumentParser(description='Compile all .hlsl shaders')
+parser.add_argument('--dxc', type=str, help='path to DXC executable')
+args = parser.parse_args()
+
+def findDXC():
+    def isExe(path):
+        return os.path.isfile(path) and os.access(path, os.X_OK)
+
+    if args.dxc != None and isExe(args.dxc):
+        return args.dxc
+
+    exe_name = "dxc"
+    if os.name == "nt":
+        exe_name += ".exe"
+
+    for exe_dir in os.environ["PATH"].split(os.pathsep):
+        full_path = os.path.join(exe_dir, exe_name)
+        if isExe(full_path):
+            return full_path
+
+    sys.exit("Could not find DXC executable on PATH, and was not specified with --dxc")
+
+dxc_path = findDXC()
+dir_path = os.path.dirname(os.path.realpath(__file__))
+dir_path = dir_path.replace('\\', '/')
+for root, dirs, files in os.walk(dir_path):
+    for file in files:
+        if file.endswith(".vert") or file.endswith(".frag") or file.endswith(".comp") or file.endswith(".geom") or file.endswith(".tesc") or file.endswith(".tese") or file.endswith(".rgen") or file.endswith(".rchit") or file.endswith(".rmiss"):
+            hlsl_file = os.path.join(root, file)
+
+            spv_out = os.path.abspath(os.path.join(dir_path, "..", "shaders", os.path.relpath(hlsl_file, dir_path) + ".spv"))
+
+            # Make the spv directory if it does not already exist
+            spv_dir = os.path.dirname(spv_out)
+            if not os.path.exists(spv_dir):
+                os.makedirs(spv_dir)
+
+            profile = ''
+            if(hlsl_file.find('.vert') != -1):
+                profile = 'vs_6_1'
+            elif(hlsl_file.find('.frag') != -1):
+                profile = 'ps_6_1'
+            elif(hlsl_file.find('.comp') != -1):
+                profile = 'cs_6_1'
+            elif(hlsl_file.find('.geom') != -1):
+                profile = 'gs_6_1'
+            elif(hlsl_file.find('.tesc') != -1):
+                profile = 'hs_6_1'
+            elif(hlsl_file.find('.tese') != -1):
+                profile = 'ds_6_1'
+            elif(hlsl_file.find('.rgen') != -1 or
+				hlsl_file.find('.rchit') != -1 or
+				hlsl_file.find('.rmiss') != -1):
+                profile = 'lib_6_3'
+
+            print('Compiling %s' % (hlsl_file))
+            subprocess.check_output([
+                dxc_path,
+                '-spirv',
+                '-T', profile,
+                '-E', 'main',
+                '-fspv-extension=SPV_NV_ray_tracing',
+                '-fspv-extension=SPV_KHR_multiview',
+                hlsl_file,
+                '-Fo', spv_out])