`fabric/graphics` module: all about graphics

Summary: `fabric/graphics` provides graphics primitives; the implementation should be platform-specific eventually.

Reviewed By: fkgozali

Differential Revision: D7230675

fbshipit-source-id: ff05d2673072fad5ee6f331f0155561969e1a8b6

ReactCommon/fabric/core/BUCK

@@ -48,5 +48,6 @@ rn_xplat_cxx_library(
         "xplat//folly:molly",
         "xplat//third-party/glog:glog",
         react_native_xplat_target("fabric/debug:debug"),
+        react_native_xplat_target("fabric/graphics:graphics"),
     ],
 )

ReactCommon/fabric/graphics/BUCK

@@ -0,0 +1,50 @@
+load("//configurations/buck/apple:flag_defs.bzl", "get_debug_preprocessor_flags")
+load("//ReactNative:DEFS.bzl", "IS_OSS_BUILD", "react_native_xplat_target", "rn_xplat_cxx_library", "APPLE_INSPECTOR_FLAGS")
+
+APPLE_COMPILER_FLAGS = []
+
+if not IS_OSS_BUILD:
+    load("@xplat//configurations/buck/apple:flag_defs.bzl", "get_static_library_ios_flags", "flags")
+    APPLE_COMPILER_FLAGS = flags.get_flag_value(get_static_library_ios_flags(), 'compiler_flags')
+
+rn_xplat_cxx_library(
+    name = "graphics",
+    srcs = glob(
+        [
+            "**/*.cpp",
+        ],
+    ),
+    headers = glob(
+        [
+            "**/*.h",
+        ],
+    ),
+    header_namespace = "",
+    exported_headers = subdir_glob(
+        [
+            ("", "*.h"),
+        ],
+        prefix = "fabric/graphics",
+    ),
+    compiler_flags = [
+        "-std=c++14",
+        "-Wall",
+        "-fexceptions",
+        "-frtti",
+    ],
+    fbobjc_compiler_flags = APPLE_COMPILER_FLAGS,
+    fbobjc_preprocessor_flags = get_debug_preprocessor_flags() + APPLE_INSPECTOR_FLAGS,
+    force_static = True,
+    preprocessor_flags = [
+        "-DLOG_TAG=\"ReactNative\"",
+        "-DWITH_FBSYSTRACE=1",
+    ],
+    visibility = ["PUBLIC"],
+    deps = [
+        "xplat//fbsystrace:fbsystrace",
+        "xplat//folly:headers_only",
+        "xplat//folly:memory",
+        "xplat//folly:molly",
+        "xplat//third-party/glog:glog",
+    ],
+)

ReactCommon/fabric/graphics/Color.cpp

@@ -0,0 +1,39 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "Color.h"
+#include <CoreGraphics/CoreGraphics.h>
+#include <CoreGraphics/CGColor.h>
+#include <cassert>
+
+namespace facebook {
+namespace react {
+
+SharedColor colorFromComponents(float red, float green, float blue, float alpha) {
+  const CGFloat components[] = {red, green, blue, alpha};
+  CGColorRef color = CGColorCreate(
+    CGColorSpaceCreateDeviceRGB(),
+    components
+  );
+
+  return SharedColor(color, CFRelease);
+}
+
+ColorComponents colorComponentsFromColor(SharedColor color) {
+  int numberOfComponents = CGColorGetNumberOfComponents(color.get());
+  assert(numberOfComponents == 4);
+  const CGFloat *components = CGColorGetComponents(color.get());
+  return ColorComponents {
+    (float)components[0],
+    (float)components[1],
+    (float)components[2],
+    (float)components[3]
+  };
+}
+
+} // namespace react
+} // namespace facebook

ReactCommon/fabric/graphics/Color.h

@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <CoreGraphics/CoreGraphics.h>
+#include <memory>
+
+namespace facebook {
+namespace react {
+
+using Color = CGColor;
+using SharedColor = std::shared_ptr<Color>;
+
+struct ColorComponents {
+  float red {0};
+  float green {0};
+  float blue {0};
+  float alpha {0};
+};
+
+SharedColor colorFromComponents(float red, float green, float blue, float alpha);
+ColorComponents colorComponentsFromColor(SharedColor color);
+
+} // namespace react
+} // namespace facebook

ReactCommon/fabric/graphics/Geometry.h

@@ -0,0 +1,60 @@
+// Copyright 2004-present Facebook. All Rights Reserved.
+
+#pragma once
+
+namespace facebook {
+namespace react {
+
+/*
+ * Exact type of float numbers which ideally should match a type behing
+ * platform- and chip-architecture-specific float type (something like
+ * CGFloat on iOS).
+ */
+using Float = double;
+
+/*
+ * Point
+ */
+struct Point {
+  Float x {0};
+  Float y {0};
+
+  Point& operator += (const Point& rhs) {
+    x += rhs.x;
+    y += rhs.y;
+    return *this;
+  }
+
+  friend Point operator + (Point lhs, const Point& rhs) {
+    return lhs += rhs;
+  }
+};
+
+/*
+ * Size
+ */
+struct Size {
+  Float width {0};
+  Float height {0};
+};
+
+/*
+ * Rect: Point and Size
+ */
+struct Rect {
+  Point origin {0, 0};
+  Size size {0, 0};
+};
+
+/*
+ * EdgeInsets
+ */
+struct EdgeInsets {
+  Float top {0};
+  Float left {0};
+  Float bottom {0};
+  Float right {0};
+};
+
+} // namespace react
+} // namespace facebook

ReactCommon/fabric/graphics/graphicValuesConversions.cpp

@@ -0,0 +1,51 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "graphicValuesConversions.h"
+
+namespace facebook {
+namespace react {
+
+SharedColor colorFromDynamic(folly::dynamic value) {
+  float red;
+  float green;
+  float blue;
+  float alpha;
+
+  if (value.isNumber()) {
+    auto argb = value.asInt();
+    float ratio = 256;
+    alpha = ((argb >> 24) & 0xFF) / ratio;
+    red = ((argb >> 16) & 0xFF) / ratio;
+    green = ((argb >> 8) & 0xFF) / ratio;
+    blue = (argb & 0xFF) / ratio;
+  } else if (value.isArray()) {
+    auto size = value.size();
+    assert(size == 3 || size == 4);
+    red = value[0].asDouble();
+    green = value[1].asDouble();
+    blue = value[2].asDouble();
+    alpha = size == 4 ? value[3].asDouble() : 1.0;
+  } else {
+    abort();
+  }
+
+  return colorFromComponents(red, green, blue, alpha);
+}
+
+std::string colorNameFromColor(SharedColor value) {
+  ColorComponents components = colorComponentsFromColor(value);
+  const float ratio = 256;
+  return "rgba(" +
+    folly::to<std::string>(round(components.red * ratio)) + ", " +
+    folly::to<std::string>(round(components.green * ratio)) + ", " +
+    folly::to<std::string>(round(components.blue * ratio)) + ", " +
+    folly::to<std::string>(round(components.alpha * ratio)) + ")";
+}
+
+} // namespace react
+} // namespace facebook

ReactCommon/fabric/graphics/graphicValuesConversions.h

@@ -0,0 +1,20 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <folly/dynamic.h>
+#include <fabric/graphics/Color.h>
+
+namespace facebook {
+namespace react {
+
+SharedColor colorFromDynamic(folly::dynamic value);
+std::string colorNameFromColor(SharedColor value);
+
+} // namespace react
+} // namespace facebook