Merge "Add tool to generate color space conversion 3D LUTs"
diff --git a/include/ui/ColorSpace.h b/include/ui/ColorSpace.h
index b1863df..e9260b5 100644
--- a/include/ui/ColorSpace.h
+++ b/include/ui/ColorSpace.h
@@ -212,14 +212,14 @@
         return v;
     }
 
-    const std::string mName;
+    std::string mName;
 
-    const mat3 mRGBtoXYZ;
-    const mat3 mXYZtoRGB;
+    mat3 mRGBtoXYZ;
+    mat3 mXYZtoRGB;
 
-    const transfer_function mOETF;
-    const transfer_function mEOTF;
-    const clamping_function mClamper;
+    transfer_function mOETF;
+    transfer_function mEOTF;
+    clamping_function mClamper;
 
     std::array<float2, 3> mPrimaries;
     float2 mWhitePoint;
diff --git a/libs/ui/tools/Android.bp b/libs/ui/tools/Android.bp
new file mode 100644
index 0000000..fb46c2b
--- /dev/null
+++ b/libs/ui/tools/Android.bp
@@ -0,0 +1,35 @@
+//
+// Copyright (C) 2017 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.
+//
+
+cc_defaults {
+    name: "libui_tools_default",
+    clang_cflags: [
+        "-Wall",
+        "-Wextra",
+        "-Werror",
+    ],
+}
+
+cc_binary {
+    name: "lutgen",
+    cppflags: [
+        "-Wall",
+        "-Wextra",
+        "-Werror",
+    ],
+    shared_libs: ["libui"],
+    srcs: ["lutgen.cpp"],
+}
diff --git a/libs/ui/tools/lutgen.cpp b/libs/ui/tools/lutgen.cpp
new file mode 100644
index 0000000..97b0822
--- /dev/null
+++ b/libs/ui/tools/lutgen.cpp
@@ -0,0 +1,196 @@
+/*
+ * Copyright 2017 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.
+ */
+
+#include <algorithm>
+#include <fstream>
+#include <iomanip>
+#include <iostream>
+#include <string>
+
+#include <getopt.h>
+
+#include <ui/ColorSpace.h>
+
+using namespace android;
+using namespace std;
+
+uint32_t gSize = 32;
+ColorSpace gColorSpaceSrc = ColorSpace::DisplayP3();
+ColorSpace gColorSpaceDst = ColorSpace::extendedSRGB();
+string gNameSrc = "DisplayP3";
+string gNameDst = "extendedSRGB";
+
+static void printHelp() {
+    cout << "lutgen -d SIZE -s SOURCE -t TARGET <lut file>" << endl;
+    cout << endl;
+    cout << "Generate a 3D LUT to convert between two color spaces." << endl;
+    cout << endl;
+    cout << "If <lut file> ends in .inc, data is generated without the array declaration." << endl;
+    cout << endl;
+    cout << "Options:" << endl;
+    cout << "  --help, -h" << endl;
+    cout << "    print this message" << endl;
+    cout << "  --dimension=, -d" << endl;
+    cout << "    the dimension of the 3D LUT. Example: 17 for a 17x17x17 LUT. 32 by default" << endl;
+    cout << "  --source=COLORSPACE, -s" << endl;
+    cout << "    the source color space, see below for available names. DisplayP3 by default" << endl;
+    cout << "  --target=COLORSPACE, -t" << endl;
+    cout << "    the target color space, see below for available names. extendedSRGB by default" << endl;
+    cout << endl;
+    cout << "Colorspace names:" << endl;
+    cout << "    sRGB" << endl;
+    cout << "    linearSRGB" << endl;
+    cout << "    extendedSRGB" << endl;
+    cout << "    linearExtendedSRGB" << endl;
+    cout << "    NTSC" << endl;
+    cout << "    BT709" << endl;
+    cout << "    BT2020" << endl;
+    cout << "    AdobeRGB" << endl;
+    cout << "    ProPhotoRGB" << endl;
+    cout << "    DisplayP3" << endl;
+    cout << "    DCIP3" << endl;
+    cout << "    ACES" << endl;
+    cout << "    ACEScg" << endl;
+}
+
+static const ColorSpace findColorSpace(const string& name) {
+    if (name == "linearSRGB") return ColorSpace::linearSRGB();
+    if (name == "extendedSRGB") return ColorSpace::extendedSRGB();
+    if (name == "linearExtendedSRGB") return ColorSpace::linearExtendedSRGB();
+    if (name == "NTSC") return ColorSpace::NTSC();
+    if (name == "BT709") return ColorSpace::BT709();
+    if (name == "BT2020") return ColorSpace::BT2020();
+    if (name == "AdobeRGB") return ColorSpace::AdobeRGB();
+    if (name == "ProPhotoRGB") return ColorSpace::ProPhotoRGB();
+    if (name == "DisplayP3") return ColorSpace::DisplayP3();
+    if (name == "DCIP3") return ColorSpace::DCIP3();
+    if (name == "ACES") return ColorSpace::ACES();
+    if (name == "ACEScg") return ColorSpace::ACEScg();
+    return ColorSpace::sRGB();
+}
+
+static int handleCommandLineArgments(int argc, char* argv[]) {
+    static constexpr const char* OPTSTR = "h:d:s:t:";
+    static const struct option OPTIONS[] = {
+            { "help",       no_argument,       0, 'h' },
+            { "dimension",  required_argument, 0, 'd' },
+            { "source",     required_argument, 0, 's' },
+            { "target",     required_argument, 0, 't' },
+            { 0, 0, 0, 0 }  // termination of the option list
+    };
+
+    int opt;
+    int index = 0;
+
+    while ((opt = getopt_long(argc, argv, OPTSTR, OPTIONS, &index)) >= 0) {
+        string arg(optarg ? optarg : "");
+        switch (opt) {
+            default:
+            case 'h':
+                printHelp();
+                exit(0);
+                break;
+            case 'd':
+                gSize = max(2, min(stoi(arg), 256));
+                break;
+            case 's':
+                gNameSrc = arg;
+                gColorSpaceSrc = findColorSpace(arg);
+                break;
+            case 't':
+                gNameDst = arg;
+                gColorSpaceDst = findColorSpace(arg);
+                break;
+        }
+    }
+
+    return optind;
+}
+
+int main(int argc, char* argv[]) {
+    int optionIndex = handleCommandLineArgments(argc, argv);
+    int numArgs = argc - optionIndex;
+
+    if (numArgs < 1) {
+        printHelp();
+        return 1;
+    }
+    
+    bool isInclude = false;
+
+    string filename(argv[optionIndex]);
+    size_t index = filename.find_last_of('.');
+
+    if (index != string::npos) {
+        string extension(filename.substr(index + 1));
+        isInclude = extension == "inc";
+    }
+
+    ofstream outputStream(filename, ios::trunc);
+    if (outputStream.good()) {
+        auto lut = ColorSpace::createLUT(gSize, gColorSpaceSrc, gColorSpaceDst);
+        auto data = lut.get();
+
+        outputStream << "// generated with lutgen " << filename.c_str() << endl;
+        outputStream << "// 3D LUT stored as an RGB16F texture, in GL order" << endl;
+        outputStream << "// Size is " << gSize << "x" << gSize << "x" << gSize << endl;
+
+        string src(gNameSrc);
+        string dst(gNameDst);
+
+        if (!isInclude) {
+            transform(src.begin(), src.end(), src.begin(), ::toupper);
+            transform(dst.begin(), dst.end(), dst.begin(), ::toupper);
+
+            outputStream << "const size_t LUT_" << src << "_TO_" << dst << "_SIZE = " << gSize << endl;
+            outputStream << "const uint16_t LUT_" << src << "_TO_" << dst << "[] = {";
+        } else {
+            outputStream << "// From " << src << " to " << dst << endl;
+        }
+
+        for (size_t z = 0; z < gSize; z++) {
+            for (size_t y = 0; y < gSize; y++) {
+                for (size_t x = 0; x < gSize; x++) {
+                    if (x % 4 == 0) outputStream << endl << "    ";
+
+                    half3 rgb = half3(*data++);
+
+                    const uint16_t r = rgb.r.getBits();
+                    const uint16_t g = rgb.g.getBits();
+                    const uint16_t b = rgb.b.getBits();
+
+                    outputStream << "0x" << setfill('0') << setw(4) << hex << r << ", ";
+                    outputStream << "0x" << setfill('0') << setw(4) << hex << g << ", ";
+                    outputStream << "0x" << setfill('0') << setw(4) << hex << b << ", ";
+                }
+            }
+        }
+
+        if (!isInclude) {
+            outputStream << endl << "}; // end LUT" << endl;
+        }
+
+        outputStream << endl;
+        outputStream.flush();
+        outputStream.close();
+    } else {
+        cerr << "Could not write to file: " << filename << endl;
+        return 1;
+
+    }
+
+    return 0;
+}