skia2/gm/userfont.cpp
Mike Reed d240d76b34 extract original paths at big size to improve precision
As part of this, start introducing more consistent factories (matching classes like SkM44)

Change-Id: I453f1856c0427b008faaed9dbba5263e53a48ce4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/290766
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Mike Reed <reed@google.com>
2020-05-19 17:27:22 +00:00

121 lines
3.5 KiB
C++

/*
* Copyright 2020 Google LLC
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "gm/gm.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkFont.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPath.h"
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "include/utils/SkCustomTypeface.h"
#include "tools/Resources.h"
static sk_sp<SkTypeface> make_tf() {
SkCustomTypefaceBuilder builder;
SkFont font;
const float upem = font.getTypefaceOrDefault()->getUnitsPerEm();
// request a big size, to improve precision at the fontscaler level
font.setSize(upem);
font.setHinting(SkFontHinting::kNone);
// so we can scale our paths back down to 1-point
const SkMatrix scale = SkMatrix::Scale(1.0f/upem, 1.0f/upem);
{
SkFontMetrics metrics;
font.getMetrics(&metrics);
builder.setMetrics(metrics, 1.0f/upem);
}
// Steal the first 128 chars from the default font
for (SkGlyphID index = 0; index <= 127; ++index) {
SkGlyphID glyph = font.unicharToGlyph(index);
SkScalar width;
font.getWidths(&glyph, 1, &width);
SkPath path;
font.getPath(glyph, &path);
// we use the charcode to be our glyph index, since we have no cmap table
builder.setGlyph(index, width/upem, path.makeTransform(scale));
}
return builder.detach();
}
#include "include/core/SkTextBlob.h"
static sk_sp<SkTypeface> round_trip(sk_sp<SkTypeface> tf) {
auto data = tf->serialize();
SkMemoryStream stream(data->data(), data->size());
return SkTypeface::MakeDeserialize(&stream);
}
class UserFontGM : public skiagm::GM {
sk_sp<SkTypeface> fTF;
public:
UserFontGM() {}
void onOnceBeforeDraw() override {
fTF = make_tf();
// test serialization
fTF = round_trip(fTF);
}
static sk_sp<SkTextBlob> make_blob(sk_sp<SkTypeface> tf, float size, float* spacing) {
SkFont font(tf);
font.setSize(size);
font.setEdging(SkFont::Edging::kAntiAlias);
*spacing = font.getMetrics(nullptr);
return SkTextBlob::MakeFromString("Typeface", font);
}
bool runAsBench() const override { return true; }
SkString onShortName() override { return SkString("user_typeface"); }
SkISize onISize() override { return {810, 452}; }
void onDraw(SkCanvas* canvas) override {
auto waterfall = [&](sk_sp<SkTypeface> tf) {
SkPaint paint;
paint.setAntiAlias(true);
float spacing;
float x = 20,
y = 16;
for (float size = 9; size <= 100; size *= 1.25f) {
auto blob = make_blob(tf, size, &spacing);
// shared baseline
if (tf == nullptr) {
paint.setColor(0xFFDDDDDD);
canvas->drawRect({0, y, 810, y+1}, paint);
}
paint.setColor(0xFFCCCCCC);
paint.setStyle(SkPaint::kStroke_Style);
canvas->drawRect(blob->bounds().makeOffset(x, y), paint);
paint.setStyle(SkPaint::kFill_Style);
paint.setColor(SK_ColorBLACK);
canvas->drawTextBlob(blob, x, y, paint);
y += SkScalarRoundToInt(spacing * 1.25f + 2);
}
};
waterfall(nullptr);
canvas->translate(400, 0);
waterfall(fTF);
}
};
DEF_GM(return new UserFontGM;)