Move all text stuff to its own folder

BUG=skia:

Review URL: https://codereview.chromium.org/1521453002

1 files changed, 176 insertions, 0 deletions

diff --git a/src/gpu/text/GrTextContext.cpp b/src/gpu/text/GrTextContext.cpp
new file mode 100644
index 0000000000..8ff2523a73
--- /dev/null
+++ b/src/gpu/text/GrTextContext.cpp
@@ -0,0 +1,176 @@
+/*
+ * Copyright 2010 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "GrTextContext.h"
+#include "GrContext.h"
+#include "GrFontScaler.h"
+#include "GrTextUtils.h"
+
+#include "SkDrawFilter.h"
+#include "SkGlyphCache.h"
+#include "SkGrPriv.h"
+#include "SkTextBlobRunIterator.h"
+
+GrTextContext::GrTextContext(GrContext* context, const SkSurfaceProps& surfaceProps)
+    : fFallbackTextContext(nullptr)
+    , fContext(context)
+    , fSurfaceProps(surfaceProps) {
+}
+
+GrTextContext::~GrTextContext() {
+    delete fFallbackTextContext;
+}
+
+void GrTextContext::drawText(GrDrawContext* dc,
+                             const GrClip& clip, const GrPaint& paint,
+                             const SkPaint& skPaint, const SkMatrix& viewMatrix,
+                             const char text[], size_t byteLength,
+                             SkScalar x, SkScalar y, const SkIRect& clipBounds) {
+    if (fContext->abandoned()) {
+        return;
+    }
+
+    GrTextContext* textContext = this;
+    do {
+        if (textContext->canDraw(skPaint, viewMatrix)) {
+            textContext->onDrawText(dc, clip, paint, skPaint, viewMatrix,
+                                    text, byteLength, x, y, clipBounds);
+            return;
+        }
+        textContext = textContext->fFallbackTextContext;
+    } while (textContext);
+
+    // fall back to drawing as a path
+    GrTextUtils::DrawTextAsPath(fContext, dc, clip, skPaint, viewMatrix, text, byteLength, x, y,
+                                clipBounds);
+}
+
+void GrTextContext::drawPosText(GrDrawContext* dc,
+                                const GrClip& clip, const GrPaint& paint,
+                                const SkPaint& skPaint, const SkMatrix& viewMatrix,
+                                const char text[], size_t byteLength,
+                                const SkScalar pos[], int scalarsPerPosition,
+                                const SkPoint& offset, const SkIRect& clipBounds) {
+    if (fContext->abandoned()) {
+        return;
+    }
+
+    GrTextContext* textContext = this;
+    do {
+        if (textContext->canDraw(skPaint, viewMatrix)) {
+            textContext->onDrawPosText(dc, clip, paint, skPaint, viewMatrix,
+                                       text, byteLength, pos,
+                                       scalarsPerPosition, offset, clipBounds);
+            return;
+        }
+        textContext = textContext->fFallbackTextContext;
+    } while (textContext);
+
+    // fall back to drawing as a path
+    GrTextUtils::DrawPosTextAsPath(fContext, dc, fSurfaceProps, clip, skPaint, viewMatrix, text,
+                                   byteLength, pos, scalarsPerPosition, offset, clipBounds);
+}
+
+bool GrTextContext::ShouldDisableLCD(const SkPaint& paint) {
+    if (!SkXfermode::AsMode(paint.getXfermode(), nullptr) ||
+        paint.getMaskFilter() ||
+        paint.getRasterizer() ||
+        paint.getPathEffect() ||
+        paint.isFakeBoldText() ||
+        paint.getStyle() != SkPaint::kFill_Style)
+    {
+        return true;
+    }
+    return false;
+}
+
+uint32_t GrTextContext::FilterTextFlags(const SkSurfaceProps& surfaceProps, const SkPaint& paint) {
+    uint32_t flags = paint.getFlags();
+
+    if (!paint.isLCDRenderText() || !paint.isAntiAlias()) {
+        return flags;
+    }
+
+    if (kUnknown_SkPixelGeometry == surfaceProps.pixelGeometry() || ShouldDisableLCD(paint)) {
+        flags &= ~SkPaint::kLCDRenderText_Flag;
+        flags |= SkPaint::kGenA8FromLCD_Flag;
+    }
+
+    return flags;
+}
+
+void GrTextContext::drawTextBlob(GrDrawContext* dc,
+                                 const GrClip& clip, const SkPaint& skPaint,
+                                 const SkMatrix& viewMatrix, const SkTextBlob* blob,
+                                 SkScalar x, SkScalar y,
+                                 SkDrawFilter* drawFilter, const SkIRect& clipBounds) {
+    SkPaint runPaint = skPaint;
+
+    SkTextBlobRunIterator it(blob);
+    for (;!it.done(); it.next()) {
+        size_t textLen = it.glyphCount() * sizeof(uint16_t);
+        const SkPoint& offset = it.offset();
+        // applyFontToPaint() always overwrites the exact same attributes,
+        // so it is safe to not re-seed the paint for this reason.
+        it.applyFontToPaint(&runPaint);
+
+        if (drawFilter && !drawFilter->filter(&runPaint, SkDrawFilter::kText_Type)) {
+            // A false return from filter() means we should abort the current draw.
+            runPaint = skPaint;
+            continue;
+        }
+
+        runPaint.setFlags(FilterTextFlags(fSurfaceProps, runPaint));
+
+        GrPaint grPaint;
+        if (!SkPaintToGrPaint(fContext, runPaint, viewMatrix, &grPaint)) {
+            return;
+        }
+
+        switch (it.positioning()) {
+        case SkTextBlob::kDefault_Positioning:
+            this->drawText(dc, clip, grPaint, runPaint, viewMatrix, (const char *)it.glyphs(),
+                           textLen, x + offset.x(), y + offset.y(), clipBounds);
+            break;
+        case SkTextBlob::kHorizontal_Positioning:
+            this->drawPosText(dc, clip, grPaint, runPaint, viewMatrix, (const char*)it.glyphs(),
+                              textLen, it.pos(), 1, SkPoint::Make(x, y + offset.y()), clipBounds);
+            break;
+        case SkTextBlob::kFull_Positioning:
+            this->drawPosText(dc, clip, grPaint, runPaint, viewMatrix, (const char*)it.glyphs(),
+                              textLen, it.pos(), 2, SkPoint::Make(x, y), clipBounds);
+            break;
+        default:
+            SkFAIL("unhandled positioning mode");
+        }
+
+        if (drawFilter) {
+            // A draw filter may change the paint arbitrarily, so we must re-seed in this case.
+            runPaint = skPaint;
+        }
+    }
+}
+
+static void GlyphCacheAuxProc(void* data) {
+    GrFontScaler* scaler = (GrFontScaler*)data;
+    SkSafeUnref(scaler);
+}
+
+GrFontScaler* GrTextContext::GetGrFontScaler(SkGlyphCache* cache) {
+    void* auxData;
+    GrFontScaler* scaler = nullptr;
+
+    if (cache->getAuxProcData(GlyphCacheAuxProc, &auxData)) {
+        scaler = (GrFontScaler*)auxData;
+    }
+    if (nullptr == scaler) {
+        scaler = new GrFontScaler(cache);
+        cache->setAuxProc(GlyphCacheAuxProc, scaler);
+    }
+
+    return scaler;
+}