| #Topic Text_Blob
|
| #Alias Text_Blob_Reference ##
|
|
|
| #Class SkTextBlob
|
|
|
| #Code
|
| #Populate
|
| ##
|
|
|
| SkTextBlob combines multiple text runs into an immutable container. Each text
|
| run consists of Glyphs, Paint, and position. Only parts of Paint related to
|
| fonts and text rendering are used by run.
|
|
|
| # ------------------------------------------------------------------------------
|
|
|
| #Method const SkRect& bounds() const
|
| #In Property
|
| #Line # returns conservative bounding box ##
|
| #Populate
|
|
|
| #Example
|
| #Height 70
|
| SkTextBlobBuilder textBlobBuilder;
|
| const char bunny[] = "/(^x^)\\";
|
| const int len = sizeof(bunny) - 1;
|
| uint16_t glyphs[len];
|
| SkPaint paint;
|
| paint.textToGlyphs(bunny, len, glyphs);
|
| paint.setTextEncoding(kGlyphID_SkTextEncoding);
|
| SkFont font;
|
| int runs[] = { 3, 1, 3 };
|
| SkPoint textPos = { 20, 50 };
|
| int glyphIndex = 0;
|
| for (auto runLen : runs) {
|
| font.setSize(1 == runLen ? 20 : 50);
|
| paint.setTextSize(1 == runLen ? 20 : 50);
|
| const SkTextBlobBuilder::RunBuffer& run =
|
| textBlobBuilder.allocRun(font, runLen, textPos.fX, textPos.fY);
|
| memcpy(run.glyphs, &glyphs[glyphIndex], sizeof(glyphs[0]) * runLen);
|
| textPos.fX += paint.measureText(&glyphs[glyphIndex], sizeof(glyphs[0]) * runLen, nullptr);
|
| glyphIndex += runLen;
|
| }
|
| sk_sp<const SkTextBlob> blob = textBlobBuilder.make();
|
| canvas->drawTextBlob(blob.get(), 0, 0, paint);
|
| paint.setStyle(SkPaint::kStroke_Style);
|
| canvas->drawRect(blob->bounds(), paint);
|
| ##
|
|
|
| #SeeAlso SkPath::getBounds
|
|
|
| #Method ##
|
|
|
| # ------------------------------------------------------------------------------
|
|
|
| #Method uint32_t uniqueID() const
|
| #In Property
|
| #Line # returns identifier for Text_Blob ##
|
| #Populate
|
|
|
| #Example
|
| for (int index = 0; index < 2; ++index) {
|
| SkTextBlobBuilder textBlobBuilder;
|
| const char bunny[] = "/(^x^)\\";
|
| const int len = sizeof(bunny) - 1;
|
| uint16_t glyphs[len];
|
| SkPaint paint;
|
| paint.textToGlyphs(bunny, len, glyphs);
|
| paint.setTextEncoding(kGlyphID_SkTextEncoding);
|
| paint.setTextScaleX(0.5);
|
| SkFont font;
|
| font.setScaleX(0.5);
|
| int runs[] = { 3, 1, 3 };
|
| SkPoint textPos = { 20, 50 };
|
| int glyphIndex = 0;
|
| for (auto runLen : runs) {
|
| font.setSize(1 == runLen ? 20 : 50);
|
| paint.setTextSize(1 == runLen ? 20 : 50);
|
| const SkTextBlobBuilder::RunBuffer& run =
|
| textBlobBuilder.allocRun(font, runLen, textPos.fX, textPos.fY);
|
| memcpy(run.glyphs, &glyphs[glyphIndex], sizeof(glyphs[0]) * runLen);
|
| textPos.fX += paint.measureText(&glyphs[glyphIndex], sizeof(glyphs[0]) * runLen, nullptr);
|
| glyphIndex += runLen;
|
| }
|
| sk_sp<const SkTextBlob> blob = textBlobBuilder.make();
|
| paint.reset();
|
| canvas->drawTextBlob(blob.get(), 0, 0, paint);
|
| std::string id = "unique ID:" + std::to_string(blob->uniqueID());
|
| canvas->drawString(id.c_str(), 30, blob->bounds().fBottom + 15, paint);
|
| canvas->translate(blob->bounds().fRight + 10, 0);
|
| }
|
| ##
|
|
|
| #SeeAlso SkRefCnt
|
|
|
| #Method ##
|
|
|
| # ------------------------------------------------------------------------------
|
|
|
| #Method int getIntercepts(const SkScalar bounds[2], SkScalar intervals[], |
| const SkPaint* paint = nullptr) const; |
| #In Utility |
| #Line # returns where lines intersect Text_Blob; underlines ## |
| #Populate |
| |
| #Example |
| #Height 143 |
| void draw(SkCanvas* canvas) { |
| SkFont font; |
| font.setSize(120); |
| SkPoint textPos = { 20, 110 }; |
| int len = 3; |
| SkTextBlobBuilder textBlobBuilder; |
| const SkTextBlobBuilder::RunBuffer& run = |
| textBlobBuilder.allocRun(font, len, textPos.fX, textPos.fY); |
| run.glyphs[0] = 10; |
| run.glyphs[1] = 20; |
| run.glyphs[2] = 30; |
| sk_sp<const SkTextBlob> blob = textBlobBuilder.make(); |
| SkPaint paint; |
| SkScalar bounds[] = { 116, 134 }; |
| int count = blob->getIntercepts(bounds, nullptr); |
| std::vector<SkScalar> intervals; |
| intervals.resize(count); |
| (void) paint.getTextBlobIntercepts(blob.get(), bounds, &intervals.front()); |
| canvas->drawTextBlob(blob.get(), 0, 0, paint); |
| paint.setColor(0xFFFF7777); |
| SkScalar x = textPos.fX; |
| for (int i = 0; i < count; i+= 2) { |
| canvas->drawRect({x, bounds[0], intervals[i], bounds[1]}, paint); |
| x = intervals[i + 1]; |
| } |
| canvas->drawRect({intervals[count - 1], bounds[0], 180, bounds[1]}, paint); |
| } |
| ## |
|
|
| #Method ##
|
|
|
| # ------------------------------------------------------------------------------
|
|
|
| #Method static sk_sp<SkTextBlob> MakeFromText(const void* text, size_t byteLength, const SkFont& font,
|
| SkTextEncoding encoding = kUTF8_SkTextEncoding)
|
| #In Constructors
|
| #Line # constructs Text_Blob with one run ##
|
|
|
| Creates Text_Blob with a single run. text meaning depends on Text_Encoding;
|
| by default, text is encoded as UTF-8.
|
|
|
| font contains attributes used to define the run text: #font_metrics#.
|
|
|
| #Param text character code points or Glyphs drawn ##
|
| #Param byteLength byte length of text array ##
|
| #Param font text size, typeface, text scale, and so on, used to draw ##
|
| #Param encoding one of: kUTF8_SkTextEncoding, kUTF16_SkTextEncoding,
|
| kUTF32_SkTextEncoding, kGlyphID_SkTextEncoding
|
| ##
|
|
|
| #Return Text_Blob constructed from one run ##
|
|
|
| #Example
|
| #Height 24
|
| SkFont font;
|
| font.setSize(24);
|
| SkPaint canvasPaint;
|
| canvasPaint.setColor(SK_ColorBLUE); // respected
|
| canvasPaint.setTextSize(2); // ignored
|
| sk_sp<SkTextBlob> blob = SkTextBlob::MakeFromText("Hello World", 11, font);
|
| canvas->drawTextBlob(blob, 20, 20, canvasPaint);
|
| ##
|
|
|
| #SeeAlso MakeFromString SkTextBlobBuilder
|
|
|
| ##
|
|
|
| # ------------------------------------------------------------------------------
|
|
|
| #Method static sk_sp<SkTextBlob> MakeFromString(const char* string, const SkFont& font,
|
| SkTextEncoding encoding = kUTF8_SkTextEncoding)
|
| #In Constructors
|
| #Line # constructs Text_Blob with one run ##
|
|
|
| Creates Text_Blob with a single run. string meaning depends on Text_Encoding;
|
| by default, string is encoded as UTF-8.
|
|
|
| font contains Font_Metrics used to define the run text: #font_metrics#.
|
|
|
| #Param string character code points or Glyphs drawn ##
|
| #Param font text size, typeface, text scale, and so on, used to draw ##
|
| #Param encoding one of: kUTF8_SkTextEncoding, kUTF16_SkTextEncoding,
|
| kUTF32_SkTextEncoding, kGlyphID_SkTextEncoding
|
| ##
|
|
|
| #Return Text_Blob constructed from one run ##
|
|
|
| #Example
|
| #Height 24
|
| SkFont font;
|
| font.setSize(24);
|
| SkPaint canvasPaint;
|
| canvasPaint.setColor(SK_ColorBLUE); // respected
|
| canvasPaint.setTextSize(2); // ignored
|
| sk_sp<SkTextBlob> blob = SkTextBlob::MakeFromString("Hello World", font);
|
| canvas->drawTextBlob(blob, 20, 20, canvasPaint);
|
| ##
|
|
|
| #SeeAlso MakeFromText SkTextBlobBuilder
|
|
|
| ##
|
|
|
| # ------------------------------------------------------------------------------
|
|
|
| #Method size_t serialize(const SkSerialProcs& procs, void* memory, size_t memory_size) const
|
| #In Utility
|
| #Line # writes Text_Blob to memory ##
|
| #Populate
|
|
|
| #Example
|
| #Height 64
|
| ###$
|
| $Function
|
| #include "SkSerialProcs.h"
|
| $$
|
| $$$#
|
| SkFont blobFont;
|
| blobFont.setSize(24);
|
| sk_sp<SkTextBlob> blob = SkTextBlob::MakeFromText("Hello World", 11, blobFont);
|
| char storage[2048];
|
| size_t used = blob->serialize(SkSerialProcs(), storage, sizeof(storage));
|
| sk_sp<SkTextBlob> copy = SkTextBlob::Deserialize(storage, used, SkDeserialProcs());
|
| canvas->drawTextBlob(copy, 20, 20, SkPaint());
|
| std::string usage = "size=" + std::to_string(sizeof(storage)) + " used=" + std::to_string(used);
|
| canvas->drawString(usage.c_str(), 20, 40, SkPaint());
|
| ##
|
|
|
| #SeeAlso Deserialize SkSerialProcs
|
|
|
| #Method ##
|
|
|
| # ------------------------------------------------------------------------------
|
|
|
| #Method sk_sp<SkData> serialize(const SkSerialProcs& procs) const
|
| #In Utility
|
| #Line # writes Text_Blob to Data ##
|
| #Populate
|
|
|
| #Example
|
| #Height 24
|
| ###$
|
| $Function
|
| #include "SkSerialProcs.h"
|
| $$
|
| $$$#
|
| SkFont blobFont;
|
| blobFont.setSize(24);
|
| sk_sp<SkTextBlob> blob = SkTextBlob::MakeFromText("Hello World", 11, blobFont);
|
| sk_sp<SkData> data = blob->serialize(SkSerialProcs());
|
| sk_sp<SkTextBlob> copy = SkTextBlob::Deserialize(data->data(), data->size(), SkDeserialProcs());
|
| canvas->drawTextBlob(copy, 20, 20, SkPaint());
|
| ##
|
|
|
| #SeeAlso Deserialize SkData SkSerialProcs
|
|
|
| #Method ##
|
|
|
| # ------------------------------------------------------------------------------
|
|
|
| #Method static sk_sp<SkTextBlob> Deserialize(const void* data, size_t size, const SkDeserialProcs& procs)
|
| #In Constructors
|
| #Line # constructs Text_Blob from memory ##
|
| #Populate
|
|
|
| #Example
|
| #Height 24
|
| #Description
|
| Text "Hacker" replaces "World!", but does not update its metrics.
|
| When drawn, "Hacker" uses the spacing computed for "World!".
|
| ##
|
| ###$
|
| $Function
|
| #include "SkSerialProcs.h"
|
| $$
|
| $$$#
|
| SkFont blobFont;
|
| blobFont.setSize(24);
|
| sk_sp<SkTextBlob> blob = SkTextBlob::MakeFromText("Hello World!", 12, blobFont);
|
| sk_sp<SkData> data = blob->serialize(SkSerialProcs());
|
| uint16_t glyphs[6];
|
| SkPaint blobPaint;
|
| blobPaint.textToGlyphs("Hacker", 6, glyphs);
|
| memcpy((char*)data->writable_data() + 0x54, glyphs, sizeof(glyphs));
|
| sk_sp<SkTextBlob> copy = SkTextBlob::Deserialize(data->data(), data->size(), SkDeserialProcs());
|
| canvas->drawTextBlob(copy, 20, 20, SkPaint());
|
| ##
|
|
|
| #SeeAlso serialize SkDeserialProcs
|
|
|
| #Method ##
|
|
|
| #Class SkTextBlob ##
|
|
|
| #Topic Text_Blob ##
|