skia2/gm/texteffects.cpp
Mike Klein ea3f014e2b sk_tool_utils -> ToolUtils, and git clang-format
sk_tool_utils doesn't really fit the naming convention
the rest of code under tools/ tends to use.

Change-Id: I45326a174101c6eb4b6149e9c742f658f2fd23b1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/202313
Auto-Submit: Mike Klein <mtklein@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
2019-03-20 18:05:42 +00:00

252 lines
8.9 KiB
C++

/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "ToolUtils.h"
#include "gm.h"
#include "SkBlurMask.h"
#include "SkBlurMaskFilter.h"
#include "SkReadBuffer.h"
#include "SkTextBlob.h"
#include "SkTo.h"
#include "SkWriteBuffer.h"
#include "Sk2DPathEffect.h"
static SkPath create_underline(const SkTDArray<SkScalar>& intersections,
SkScalar last, SkScalar finalPos,
SkScalar uPos, SkScalar uWidth, SkScalar textSize) {
SkPath underline;
SkScalar end = last;
for (int index = 0; index < intersections.count(); index += 2) {
SkScalar start = intersections[index] - uWidth;
end = intersections[index + 1] + uWidth;
if (start > last && last + textSize / 12 < start) {
underline.moveTo(last, uPos);
underline.lineTo(start, uPos);
}
last = end;
}
if (end < finalPos) {
underline.moveTo(end, uPos);
underline.lineTo(finalPos, uPos);
}
return underline;
}
namespace {
sk_sp<SkTextBlob> MakeFancyBlob(const SkPaint& paint, const SkFont& font, const char* text) {
const size_t textLen = strlen(text);
const int glyphCount = font.countText(text, textLen, kUTF8_SkTextEncoding);
SkAutoTArray<SkGlyphID> glyphs(glyphCount);
font.textToGlyphs(text, textLen, kUTF8_SkTextEncoding, glyphs.get(), glyphCount);
SkAutoTArray<SkScalar> widths(glyphCount);
font.getWidths(glyphs.get(), glyphCount, widths.get());
SkTextBlobBuilder blobBuilder;
int glyphIndex = 0;
SkScalar advance = 0;
// Default-positioned run.
{
const int defaultRunLen = glyphCount / 3;
const SkTextBlobBuilder::RunBuffer& buf = blobBuilder.allocRun(font,
defaultRunLen,
advance, 0);
memcpy(buf.glyphs, glyphs.get(), SkTo<uint32_t>(defaultRunLen) * sizeof(SkGlyphID));
for (int i = 0; i < defaultRunLen; ++i) {
advance += widths[glyphIndex++];
}
}
// Horizontal-positioned run.
{
const int horizontalRunLen = glyphCount / 3;
const SkTextBlobBuilder::RunBuffer& buf = blobBuilder.allocRunPosH(font,
horizontalRunLen,
0);
memcpy(buf.glyphs, glyphs.get() + glyphIndex,
SkTo<uint32_t>(horizontalRunLen) * sizeof(SkGlyphID));
for (int i = 0; i < horizontalRunLen; ++i) {
buf.pos[i] = advance;
advance += widths[glyphIndex++];
}
}
// Full-positioned run.
{
const int fullRunLen = glyphCount - glyphIndex;
const SkTextBlobBuilder::RunBuffer& buf = blobBuilder.allocRunPos(font, fullRunLen);
memcpy(buf.glyphs, glyphs.get() + glyphIndex,
SkTo<uint32_t>(fullRunLen) * sizeof(SkGlyphID));
for (int i = 0; i < fullRunLen; ++i) {
buf.pos[i * 2 + 0] = advance; // x offset
buf.pos[i * 2 + 1] = 0; // y offset
advance += widths[glyphIndex++];
}
}
return blobBuilder.make();
}
} // anonymous ns
DEF_SIMPLE_GM(fancyblobunderline, canvas, 1480, 1380) {
SkPaint paint;
paint.setAntiAlias(true);
const char* fam[] = { "sans-serif", "serif", "monospace" };
const char test[] = "aAjJgGyY_|{-(~[,]qQ}pP}zZ";
const SkPoint blobOffset = { 10, 80 };
for (size_t font = 0; font < SK_ARRAY_COUNT(fam); ++font) {
for (SkScalar textSize = 100; textSize > 10; textSize -= 20) {
SkFont skFont(ToolUtils::create_portable_typeface(fam[font], SkFontStyle()), textSize);
const SkScalar uWidth = textSize / 15;
paint.setStrokeWidth(uWidth);
paint.setStyle(SkPaint::kFill_Style);
sk_sp<SkTextBlob> blob = MakeFancyBlob(paint, skFont, test);
canvas->drawTextBlob(blob, blobOffset.x(), blobOffset.y(), paint);
const SkScalar uPos = uWidth;
const SkScalar bounds[2] = { uPos - uWidth / 2, uPos + uWidth / 2 };
const int interceptCount = blob->getIntercepts(bounds, nullptr, &paint);
SkASSERT(!(interceptCount % 2));
SkTDArray<SkScalar> intercepts;
intercepts.setCount(interceptCount);
blob->getIntercepts(bounds, intercepts.begin(), &paint);
const SkScalar start = blob->bounds().left();
const SkScalar end = blob->bounds().right();
SkPath underline = create_underline(intercepts, start, end, uPos, uWidth, textSize);
underline.offset(blobOffset.x(), blobOffset.y());
paint.setStyle(SkPaint::kStroke_Style);
canvas->drawPath(underline, paint);
canvas->translate(0, textSize * 1.3f);
}
canvas->translate(0, 60);
}
}
///////////////////////////////////////////////////////////////////////////////////////////////////
static sk_sp<SkTextBlob> make_text(const SkFont& font, const SkGlyphID glyphs[], int count) {
return SkTextBlob::MakeFromText(glyphs, count * sizeof(SkGlyphID), font,
kGlyphID_SkTextEncoding);
}
static sk_sp<SkTextBlob> make_posh(const SkFont& font, const SkGlyphID glyphs[], int count,
SkScalar spacing) {
SkAutoTArray<SkScalar> xpos(count);
font.getXPos(glyphs, count, xpos.get());
for (int i = 1; i < count; ++i) {
xpos[i] += spacing * i;
}
return SkTextBlob::MakeFromPosTextH(glyphs, count * sizeof(SkGlyphID), xpos.get(), 0, font,
kGlyphID_SkTextEncoding);
}
static sk_sp<SkTextBlob> make_pos(const SkFont& font, const SkGlyphID glyphs[], int count,
SkScalar spacing) {
SkAutoTArray<SkPoint> pos(count);
font.getPos(glyphs, count, pos.get());
for (int i = 1; i < count; ++i) {
pos[i].fX += spacing * i;
}
return SkTextBlob::MakeFromPosText(glyphs, count * sizeof(SkGlyphID), pos.get(), font,
kGlyphID_SkTextEncoding);
}
// widen the gaps with a margin (on each side of the gap), elimnating segments that go away
static int trim_with_halo(SkScalar intervals[], int count, SkScalar margin) {
SkASSERT(count > 0 && (count & 1) == 0);
int n = count;
SkScalar* stop = intervals + count;
*intervals++ -= margin;
while (intervals < stop - 1) {
intervals[0] += margin;
intervals[1] -= margin;
if (intervals[0] >= intervals[1]) { // went away
int remaining = stop - intervals - 2;
SkASSERT(remaining >= 0 && (remaining & 1) == 1);
if (remaining > 0) {
memmove(intervals, intervals + 2, remaining * sizeof(SkScalar));
}
stop -= 2;
n -= 2;
} else {
intervals += 2;
}
}
*intervals += margin;
return n;
}
static void draw_blob_adorned(SkCanvas* canvas, sk_sp<SkTextBlob> blob) {
SkPaint paint;
canvas->drawTextBlob(blob.get(), 0, 0, paint);
const SkScalar yminmax[] = { 8, 16 };
int count = blob->getIntercepts(yminmax, nullptr);
if (!count) {
return;
}
SkAutoTArray<SkScalar> intervals(count);
blob->getIntercepts(yminmax, intervals.get());
count = trim_with_halo(intervals.get(), count, SkScalarHalf(yminmax[1] - yminmax[0]) * 1.5f);
SkASSERT(count >= 2);
const SkScalar y = SkScalarAve(yminmax[0], yminmax[1]);
SkScalar end = 900;
SkPath path;
path.moveTo({0, y});
for (int i = 0; i < count; i += 2) {
path.lineTo(intervals[i], y).moveTo(intervals[i+1], y);
}
if (intervals[count - 1] < end) {
path.lineTo(end, y);
}
paint.setAntiAlias(true);
paint.setStyle(SkPaint::kStroke_Style);
paint.setStrokeWidth(yminmax[1] - yminmax[0]);
canvas->drawPath(path, paint);
}
DEF_SIMPLE_GM(textblob_intercepts, canvas, 940, 800) {
const char text[] = "Hyjay {worlp}.";
const size_t length = strlen(text);
SkFont font;
font.setTypeface(ToolUtils::create_portable_typeface());
font.setSize(100);
font.setEdging(SkFont::Edging::kAntiAlias);
const int count = font.countText(text, length, kUTF8_SkTextEncoding);
SkAutoTArray<SkGlyphID> glyphs(count);
font.textToGlyphs(text, length, kUTF8_SkTextEncoding, glyphs.get(), count);
auto b0 = make_text(font, glyphs.get(), count);
canvas->translate(20, 120);
draw_blob_adorned(canvas, b0);
for (SkScalar spacing = 0; spacing < 30; spacing += 20) {
auto b1 = make_posh(font, glyphs.get(), count, spacing);
auto b2 = make_pos( font, glyphs.get(), count, spacing);
canvas->translate(0, 150);
draw_blob_adorned(canvas, b1);
canvas->translate(0, 150);
draw_blob_adorned(canvas, b2);
}
}