libs/hwui/jni/text/MeasuredText.cpp

/*
 * 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.
 */

#include "GraphicsJNI.h"
#include "utils/misc.h"
#include "utils/Log.h"
#include <nativehelper/ScopedStringChars.h>
#include <nativehelper/ScopedPrimitiveArray.h>
#include <cstdint>
#include <vector>
#include <list>
#include <algorithm>

#include "SkPaint.h"
#include "SkTypeface.h"
#include <hwui/MinikinSkia.h>
#include <hwui/MinikinUtils.h>
#include <hwui/Paint.h>
#include <minikin/FontCollection.h>
#include <minikin/AndroidLineBreakerHelper.h>
#include <minikin/MinikinFont.h>

namespace android {

static inline minikin::MeasuredTextBuilder* toBuilder(jlong ptr) {
    return reinterpret_cast<minikin::MeasuredTextBuilder*>(ptr);
}

static inline Paint* toPaint(jlong ptr) {
    return reinterpret_cast<Paint*>(ptr);
}

static inline minikin::MeasuredText* toMeasuredParagraph(jlong ptr) {
    return reinterpret_cast<minikin::MeasuredText*>(ptr);
}

template<typename Ptr> static inline jlong toJLong(Ptr ptr) {
    return reinterpret_cast<jlong>(ptr);
}

static void releaseMeasuredParagraph(jlong measuredTextPtr) {
    delete toMeasuredParagraph(measuredTextPtr);
}

// Regular JNI
static jlong nInitBuilder(CRITICAL_JNI_PARAMS) {
    return toJLong(new minikin::MeasuredTextBuilder());
}

// Regular JNI
static void nAddStyleRun(JNIEnv* /* unused */, jclass /* unused */, jlong builderPtr,
                         jlong paintPtr, jint lbStyle, jint lbWordStyle, jboolean hyphenation,
                         jint start, jint end, jboolean isRtl) {
    Paint* paint = toPaint(paintPtr);
    const Typeface* typeface = Typeface::resolveDefault(paint->getAndroidTypeface());
    minikin::MinikinPaint minikinPaint = MinikinUtils::prepareMinikinPaint(paint, typeface);
    toBuilder(builderPtr)
            ->addStyleRun(start, end, std::move(minikinPaint), lbStyle, lbWordStyle, hyphenation,
                          isRtl);
}

// Regular JNI
static void nAddReplacementRun(JNIEnv* /* unused */, jclass /* unused */, jlong builderPtr,
                               jlong paintPtr, jint start, jint end, jfloat width) {
    toBuilder(builderPtr)->addReplacementRun(start, end, width,
                                             toPaint(paintPtr)->getMinikinLocaleListId());
}

// Regular JNI
static jlong nBuildMeasuredText(JNIEnv* env, jclass /* unused */, jlong builderPtr, jlong hintPtr,
                                jcharArray javaText, jboolean computeHyphenation,
                                jboolean computeLayout, jboolean computeBounds,
                                jboolean fastHyphenationMode) {
    ScopedCharArrayRO text(env, javaText);
    const minikin::U16StringPiece textBuffer(text.get(), text.size());

    // Pass the ownership to Java.
    return toJLong(toBuilder(builderPtr)
                           ->build(textBuffer, computeHyphenation, computeLayout, computeBounds,
                                   fastHyphenationMode, toMeasuredParagraph(hintPtr))
                           .release());
}

// Regular JNI
static void nFreeBuilder(JNIEnv* env, jclass /* unused */, jlong builderPtr) {
    delete toBuilder(builderPtr);
}

// CriticalNative
static jfloat nGetWidth(CRITICAL_JNI_PARAMS_COMMA jlong ptr, jint start, jint end) {
    minikin::MeasuredText* mt = toMeasuredParagraph(ptr);
    float r = 0.0f;
    for (int i = start; i < end; ++i) {
        r += mt->widths[i];
    }
    return r;
}

static jfloat nGetCharWidthAt(CRITICAL_JNI_PARAMS_COMMA jlong ptr, jint offset) {
    return toMeasuredParagraph(ptr)->widths[offset];
}

// Regular JNI
static void nGetBounds(JNIEnv* env, jobject, jlong ptr, jcharArray javaText, jint start, jint end,
                       jobject bounds) {
    ScopedCharArrayRO text(env, javaText);
    const minikin::U16StringPiece textBuffer(text.get(), text.size());
    const minikin::Range range(start, end);

    minikin::MinikinRect rect = toMeasuredParagraph(ptr)->getBounds(textBuffer, range);

    SkRect r;
    r.fLeft = rect.mLeft;
    r.fTop = rect.mTop;
    r.fRight = rect.mRight;
    r.fBottom = rect.mBottom;

    SkIRect ir;
    r.roundOut(&ir);
    GraphicsJNI::irect_to_jrect(ir, env, bounds);
}

// Regular JNI
static jlong nGetExtent(JNIEnv* env, jobject, jlong ptr, jcharArray javaText, jint start,
                        jint end) {
    ScopedCharArrayRO text(env, javaText);
    const minikin::U16StringPiece textBuffer(text.get(), text.size());
    const minikin::Range range(start, end);

    minikin::MinikinExtent extent = toMeasuredParagraph(ptr)->getExtent(textBuffer, range);

    int32_t ascent = SkScalarRoundToInt(extent.ascent);
    int32_t descent = SkScalarRoundToInt(extent.descent);

    return (((jlong)(ascent)) << 32) | ((jlong)descent);
}

// CriticalNative
static jlong nGetReleaseFunc(CRITICAL_JNI_PARAMS) {
    return toJLong(&releaseMeasuredParagraph);
}

static jint nGetMemoryUsage(CRITICAL_JNI_PARAMS_COMMA jlong ptr) {
    return static_cast<jint>(toMeasuredParagraph(ptr)->getMemoryUsage());
}

static const JNINativeMethod gMTBuilderMethods[] = {
        // MeasuredParagraphBuilder native functions.
        {"nInitBuilder", "()J", (void*)nInitBuilder},
        {"nAddStyleRun", "(JJIIZIIZ)V", (void*)nAddStyleRun},
        {"nAddReplacementRun", "(JJIIF)V", (void*)nAddReplacementRun},
        {"nBuildMeasuredText", "(JJ[CZZZZ)J", (void*)nBuildMeasuredText},
        {"nFreeBuilder", "(J)V", (void*)nFreeBuilder},
};

static const JNINativeMethod gMTMethods[] = {
        // MeasuredParagraph native functions.
        {"nGetWidth", "(JII)F", (void*)nGetWidth},                             // Critical Natives
        {"nGetBounds", "(J[CIILandroid/graphics/Rect;)V", (void*)nGetBounds},  // Regular JNI
        {"nGetExtent", "(J[CII)J", (void*)nGetExtent},                         // Regular JNI
        {"nGetReleaseFunc", "()J", (void*)nGetReleaseFunc},                    // Critical Natives
        {"nGetMemoryUsage", "(J)I", (void*)nGetMemoryUsage},                   // Critical Native
        {"nGetCharWidthAt", "(JI)F", (void*)nGetCharWidthAt},                  // Critical Native
};

int register_android_graphics_text_MeasuredText(JNIEnv* env) {
    return RegisterMethodsOrDie(env, "android/graphics/text/MeasuredText",
            gMTMethods, NELEM(gMTMethods))
        + RegisterMethodsOrDie(env, "android/graphics/text/MeasuredText$Builder",
            gMTBuilderMethods, NELEM(gMTBuilderMethods));
}

}