1/*
2 * Copyright 2021 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include <jni.h>
9
10#include "experimental/sktext/src/Paint.h"
11#include "modules/androidkit/src/Utils.h"
12#include <string>
13
14using namespace skia::text;
15
16namespace {
17
18// conversion function for passing jstrings to SkText static calls
19static std::u16string JStringToU16String(JNIEnv* env, const jstring& jstr) {
20    const jchar* u16 = env->GetStringChars(jstr, nullptr);
21    std::u16string str(reinterpret_cast<const char16_t*>(u16), env->GetStringLength(jstr));
22    env->ReleaseStringChars(jstr, u16);
23    return str;
24}
25
26static void Text_RenderText(JNIEnv* env, jobject, jstring jtext,
27                            jlong native_canvas, jlong native_fg_paint,
28                            jfloat x, jfloat y) {
29    auto* canvas = reinterpret_cast<SkCanvas*>(native_canvas);
30    auto foreground = reinterpret_cast<SkPaint*>(native_fg_paint);
31    std::u16string u16str = JStringToU16String(env, jtext);
32    if (canvas && foreground) {
33        SkPaint background(SkColors::kTransparent);
34        Paint::drawText(u16str, canvas,
35                        skia::text::TextDirection::kLtr, skia::text::TextAlign::kLeft,
36                        *foreground, background, SkString("arial"), 50, SkFontStyle::Bold(), x, y);
37    }
38}
39
40} //namespace
41
42int register_androidkit_Text(JNIEnv* env) {
43    static const JNINativeMethod methods[] = {
44        {"nRenderText", "(Ljava/lang/String;JJFF)V", reinterpret_cast<void*>(Text_RenderText)},
45    };
46
47    const auto clazz = env->FindClass("org/skia/androidkit/Text");
48    return clazz
49        ? env->RegisterNatives(clazz, methods, SK_ARRAY_COUNT(methods))
50        : JNI_ERR;
51}
52