Add SkPictureRecord subclass that computes bounding boxes.
Review URL: https://codereview.appspot.com/6506082
git-svn-id: http://skia.googlecode.com/svn/trunk@5423 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gyp/core.gypi b/gyp/core.gypi
index 9e416ac..2c3f4d4 100644
--- a/gyp/core.gypi
+++ b/gyp/core.gypi
@@ -15,6 +15,8 @@
'<(skia_src_path)/core/SkAlphaRuns.cpp',
'<(skia_src_path)/core/SkAntiRun.h',
'<(skia_src_path)/core/SkBBoxHierarchy.h',
+ '<(skia_src_path)/core/SkBBoxRecord.cpp',
+ '<(skia_src_path)/core/SkBBoxRecord.h',
'<(skia_src_path)/core/SkBitmap.cpp',
'<(skia_src_path)/core/SkBitmapHeap.cpp',
'<(skia_src_path)/core/SkBitmapHeap.h',
diff --git a/src/core/SkBBoxRecord.cpp b/src/core/SkBBoxRecord.cpp
new file mode 100644
index 0000000..04661d0
--- /dev/null
+++ b/src/core/SkBBoxRecord.cpp
@@ -0,0 +1,253 @@
+
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkBBoxRecord.h"
+
+void SkBBoxRecord::drawRect(const SkRect& rect, const SkPaint& paint) {
+ if (this->transformBounds(rect, &paint)) {
+ INHERITED::drawRect(rect, paint);
+ }
+}
+
+void SkBBoxRecord::drawPath(const SkPath& path, const SkPaint& paint) {
+ if (this->transformBounds(path.getBounds(), &paint)) {
+ INHERITED::drawPath(path, paint);
+ }
+}
+
+void SkBBoxRecord::drawPoints(PointMode mode, size_t count, const SkPoint pts[],
+ const SkPaint& paint) {
+ SkRect bbox;
+ bbox.set(pts, count);
+ if (this->transformBounds(bbox, &paint)) {
+ INHERITED::drawPoints(mode, count, pts, paint);
+ }
+}
+
+void SkBBoxRecord::drawPaint(const SkPaint& paint) {
+ SkRect bbox;
+ if (this->getClipBounds(&bbox)) {
+ if (this->transformBounds(bbox, &paint)) {
+ INHERITED::drawPaint(paint);
+ }
+ }
+}
+
+void SkBBoxRecord::clear(SkColor color) {
+ SkISize size = this->getDeviceSize();
+ SkRect bbox = {0, 0, size.width(), size.height()};
+ this->handleBBox(bbox);
+ INHERITED::clear(color);
+}
+
+void SkBBoxRecord::drawText(const void* text, size_t byteLength, SkScalar x, SkScalar y,
+ const SkPaint& paint) {
+ SkRect bbox;
+ paint.measureText(text, byteLength, &bbox);
+ SkPaint::FontMetrics metrics;
+ paint.getFontMetrics(&metrics);
+
+ // Vertical and aligned text need to be offset
+ if (paint.isVerticalText()) {
+ SkScalar h = bbox.fBottom - bbox.fTop;
+ if (paint.getTextAlign() == SkPaint::kCenter_Align) {
+ bbox.fTop -= h / 2;
+ bbox.fBottom -= h / 2;
+ }
+ // Pad top and bottom with max extents from FontMetrics
+ bbox.fBottom += metrics.fBottom;
+ bbox.fTop += metrics.fTop;
+ } else {
+ SkScalar w = bbox.fRight - bbox.fLeft;
+ if (paint.getTextAlign() == SkPaint::kCenter_Align) {
+ bbox.fLeft -= w / 2;
+ bbox.fRight -= w / 2;
+ } else if (paint.getTextAlign() == SkPaint::kRight_Align) {
+ bbox.fLeft -= w;
+ bbox.fRight -= w;
+ }
+ // Set vertical bounds to max extents from font metrics
+ bbox.fTop = metrics.fTop;
+ bbox.fBottom = metrics.fBottom;
+ }
+
+ // Pad horizontal bounds on each side by half of max vertical extents (this is sort of
+ // arbitrary, but seems to produce reasonable results, if there were a way of getting max
+ // glyph X-extents to pad by, that may be better here, but FontMetrics fXMin and fXMax seem
+ // incorrect on most platforms (too small in Linux, never even set in Windows).
+ SkScalar pad = (metrics.fBottom - metrics.fTop) / 2;
+ bbox.fLeft -= pad;
+ bbox.fRight += pad;
+
+ bbox.fLeft += x;
+ bbox.fRight += x;
+ bbox.fTop += y;
+ bbox.fBottom += y;
+ if (this->transformBounds(bbox, &paint)) {
+ INHERITED::drawText(text, byteLength, x, y, paint);
+ }
+}
+
+void SkBBoxRecord::drawBitmap(const SkBitmap& bitmap, SkScalar left, SkScalar top,
+ const SkPaint* paint) {
+ SkRect bbox = {left, top, left + bitmap.width(), top + bitmap.height()};
+ if (this->transformBounds(bbox, paint)) {
+ INHERITED::drawBitmap(bitmap, left, top, paint);
+ }
+}
+
+void SkBBoxRecord::drawBitmapRect(const SkBitmap& bitmap, const SkIRect* src,
+ const SkRect& dst, const SkPaint* paint) {
+ if (this->transformBounds(dst, paint)) {
+ INHERITED::drawBitmapRect(bitmap, src, dst, paint);
+ }
+}
+
+void SkBBoxRecord::drawBitmapMatrix(const SkBitmap& bitmap, const SkMatrix& mat,
+ const SkPaint* paint) {
+ SkMatrix m = mat;
+ SkRect bbox = {0, 0, bitmap.width(), bitmap.height()};
+ m.mapRect(&bbox);
+ if (this->transformBounds(bbox, paint)) {
+ INHERITED::drawBitmapMatrix(bitmap, mat, paint);
+ }
+}
+
+void SkBBoxRecord::drawBitmapNine(const SkBitmap& bitmap, const SkIRect& center,
+ const SkRect& dst, const SkPaint* paint) {
+ if (this->transformBounds(dst, paint)) {
+ INHERITED::drawBitmapNine(bitmap, center, dst, paint);
+ }
+}
+
+void SkBBoxRecord::drawPosText(const void* text, size_t byteLength,
+ const SkPoint pos[], const SkPaint& paint) {
+ SkRect bbox;
+ bbox.set(pos, paint.countText(text, byteLength));
+ SkPaint::FontMetrics metrics;
+ paint.getFontMetrics(&metrics);
+ bbox.fTop += metrics.fTop;
+ bbox.fBottom += metrics.fBottom;
+
+ // pad on left and right by half of max vertical glyph extents
+ SkScalar pad = (metrics.fTop - metrics.fBottom) / 2;
+ bbox.fLeft += pad;
+ bbox.fRight -= pad;
+
+ if (this->transformBounds(bbox, &paint)) {
+ INHERITED::drawPosText(text, byteLength, pos, paint);
+ }
+}
+
+void SkBBoxRecord::drawPosTextH(const void* text, size_t byteLength, const SkScalar xpos[],
+ SkScalar constY, const SkPaint& paint) {
+ SkRect bbox;
+ size_t numChars = paint.countText(text, byteLength);
+ if (numChars > 0) {
+ bbox.fLeft = xpos[0];
+ bbox.fRight = xpos[numChars - 1];
+ // if we had a guarantee that these will be monotonically increasing, this could be sped up
+ for (size_t i = 1; i < numChars; ++i) {
+ if (xpos[i] < bbox.fLeft) {
+ bbox.fLeft = xpos[i];
+ }
+ if (xpos[i] > bbox.fRight) {
+ bbox.fRight = xpos[i];
+ }
+ }
+ SkPaint::FontMetrics metrics;
+ paint.getFontMetrics(&metrics);
+
+ // pad horizontally by half max glyph height
+ SkScalar pad = (metrics.fTop - metrics.fBottom) / 2;
+ bbox.fLeft += pad;
+ bbox.fRight -= pad;
+
+ bbox.fTop = metrics.fTop + constY;
+ bbox.fBottom = metrics.fBottom + constY;
+ if (!this->transformBounds(bbox, &paint)) {
+ return;
+ }
+ }
+ INHERITED::drawPosTextH(text, byteLength, xpos, constY, paint);
+}
+
+void SkBBoxRecord::drawSprite(const SkBitmap& bitmap, int left, int top,
+ const SkPaint* paint) {
+ SkRect bbox = {left, top, left + bitmap.width(), top + bitmap.height()};
+ this->handleBBox(bbox); // directly call handleBBox, matrix is ignored
+ INHERITED::drawBitmap(bitmap, left, top, paint);
+}
+
+void SkBBoxRecord::drawTextOnPath(const void* text, size_t byteLength,
+ const SkPath& path, const SkMatrix* matrix,
+ const SkPaint& paint) {
+ SkRect bbox = path.getBounds();
+ SkPaint::FontMetrics metrics;
+ paint.getFontMetrics(&metrics);
+
+ // pad out all sides by the max glyph height above baseline
+ SkScalar pad = metrics.fTop;
+ bbox.fLeft += pad;
+ bbox.fRight -= pad;
+ bbox.fTop += pad;
+ bbox.fBottom -= pad;
+
+ if (this->transformBounds(bbox, &paint)) {
+ INHERITED::drawTextOnPath(text, byteLength, path, matrix, paint);
+ }
+}
+
+void SkBBoxRecord::drawVertices(VertexMode mode, int vertexCount,
+ const SkPoint vertices[], const SkPoint texs[],
+ const SkColor colors[], SkXfermode* xfer,
+ const uint16_t indices[], int indexCount,
+ const SkPaint& paint) {
+ SkRect bbox;
+ bbox.set(vertices, vertexCount);
+ if (this->transformBounds(bbox, &paint)) {
+ INHERITED::drawVertices(mode, vertexCount, vertices, texs,
+ colors, xfer, indices, indexCount, paint);
+ }
+}
+
+void SkBBoxRecord::drawPicture(SkPicture& picture) {
+ SkRect bbox = {0, 0, picture.width(), picture.height()};
+ if (this->transformBounds(bbox, NULL)) {
+ INHERITED::drawPicture(picture);
+ }
+}
+
+bool SkBBoxRecord::transformBounds(const SkRect& bounds, const SkPaint* paint) {
+ SkRect outBounds = bounds;
+
+ if (paint) {
+ // account for stroking, path effects, shadows, etc
+ if (paint->canComputeFastBounds()) {
+ SkRect temp;
+ outBounds = paint->computeFastBounds(bounds, &temp);
+ } else {
+ // set bounds to current clip
+ if (!this->getClipBounds(&outBounds)) {
+ // current clip is empty
+ return false;
+ }
+ }
+ }
+
+ SkRect clip;
+
+ if (this->getClipBounds(&clip) && outBounds.intersect(clip)) {
+ this->getTotalMatrix().mapRect(&outBounds);
+ this->handleBBox(outBounds);
+ return true;
+ }
+
+ return false;
+}
+
diff --git a/src/core/SkBBoxRecord.h b/src/core/SkBBoxRecord.h
new file mode 100644
index 0000000..5a90727
--- /dev/null
+++ b/src/core/SkBBoxRecord.h
@@ -0,0 +1,76 @@
+
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkBBoxRecord_DEFINED
+#define SkBBoxRecord_DEFINED
+
+#include "SkPictureRecord.h"
+
+/**
+ * This is an abstract SkPictureRecord subclass that intercepts draw calls and computes an
+ * axis-aligned bounding box for each draw that it sees, subclasses implement handleBBox()
+ * which will be called every time we get a new bounding box.
+ */
+class SkBBoxRecord : public SkPictureRecord {
+public:
+
+ SkBBoxRecord(uint32_t recordFlags) :INHERITED(recordFlags) { }
+ virtual ~SkBBoxRecord() { }
+
+ /**
+ * This is called each time we get a bounding box, it will be axis-aligned,
+ * in device coordinates, and expanded to include stroking, shadows, etc.
+ */
+ virtual void handleBBox(const SkRect& bbox) = 0;
+
+ virtual void drawRect(const SkRect& rect, const SkPaint& paint) SK_OVERRIDE;
+ virtual void drawPath(const SkPath& path, const SkPaint& paint) SK_OVERRIDE;
+ virtual void drawPoints(PointMode mode, size_t count, const SkPoint pts[],
+ const SkPaint& paint) SK_OVERRIDE;
+ virtual void drawPaint(const SkPaint& paint) SK_OVERRIDE;
+ virtual void clear(SkColor) SK_OVERRIDE;
+ virtual void drawText(const void* text, size_t byteLength, SkScalar x, SkScalar y,
+ const SkPaint& paint) SK_OVERRIDE;
+ virtual void drawBitmap(const SkBitmap& bitmap, SkScalar left, SkScalar top,
+ const SkPaint* paint = NULL) SK_OVERRIDE;
+ virtual void drawBitmapRect(const SkBitmap& bitmap, const SkIRect* src,
+ const SkRect& dst, const SkPaint* paint) SK_OVERRIDE;
+ virtual void drawBitmapMatrix(const SkBitmap& bitmap, const SkMatrix& mat,
+ const SkPaint* paint) SK_OVERRIDE;
+ virtual void drawBitmapNine(const SkBitmap& bitmap, const SkIRect& center,
+ const SkRect& dst, const SkPaint* paint) SK_OVERRIDE;
+ virtual void drawPosText(const void* text, size_t byteLength,
+ const SkPoint pos[], const SkPaint& paint) SK_OVERRIDE;
+ virtual void drawPosTextH(const void* text, size_t byteLength,
+ const SkScalar xpos[], SkScalar constY,
+ const SkPaint& paint) SK_OVERRIDE;
+ virtual void drawSprite(const SkBitmap& bitmap, int left, int top,
+ const SkPaint* paint) SK_OVERRIDE;
+ virtual void drawTextOnPath(const void* text, size_t byteLength,
+ const SkPath& path, const SkMatrix* matrix,
+ const SkPaint& paint) SK_OVERRIDE;
+ virtual void drawVertices(VertexMode mode, int vertexCount,
+ const SkPoint vertices[], const SkPoint texs[],
+ const SkColor colors[], SkXfermode* xfer,
+ const uint16_t indices[], int indexCount,
+ const SkPaint& paint) SK_OVERRIDE;
+ virtual void drawPicture(SkPicture& picture) SK_OVERRIDE;
+
+private:
+ /**
+ * Takes a bounding box in current canvas view space, accounts for stroking and effects, and
+ * computes an axis-aligned bounding box in device coordinates, then passes it to handleBBox()
+ * returns false if the draw is completely clipped out, and may safely be ignored.
+ **/
+ bool transformBounds(const SkRect& bounds, const SkPaint* paint);
+
+ typedef SkPictureRecord INHERITED;
+};
+
+#endif
+