1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#pragma once
18
19#include <cutils/compiler.h>
20#include <utils/Functor.h>
21
22#include "GlFunctorLifecycleListener.h"
23#include "utils/Macros.h"
24#include <androidfw/ResourceTypes.h>
25
26#include <SkBitmap.h>
27#include <SkCanvas.h>
28#include <SkMatrix.h>
29
30class SkCanvasState;
31
32namespace minikin {
33    class Layout;
34}
35
36namespace android {
37
38namespace uirenderer {
39    class CanvasPropertyPaint;
40    class CanvasPropertyPrimitive;
41    class DeferredLayerUpdater;
42    class DisplayList;
43    class RenderNode;
44}
45
46namespace SaveFlags {
47
48// These must match the corresponding Canvas API constants.
49enum {
50    Matrix        = 0x01,
51    Clip          = 0x02,
52    HasAlphaLayer = 0x04,
53    ClipToLayer   = 0x10,
54
55    // Helper constant
56    MatrixClip    = Matrix | Clip,
57};
58typedef uint32_t Flags;
59
60} // namespace SaveFlags
61
62namespace uirenderer {
63class SkiaCanvasProxy;
64namespace VectorDrawable {
65class Tree;
66};
67};
68typedef uirenderer::VectorDrawable::Tree VectorDrawableRoot;
69
70class Bitmap;
71class Paint;
72struct Typeface;
73
74class ANDROID_API Canvas {
75public:
76    virtual ~Canvas() {};
77
78    static Canvas* create_canvas(const SkBitmap& bitmap);
79
80    /**
81     *  Create a new Canvas object that records view system drawing operations for deferred
82     *  rendering. A canvas returned by this call supports calls to the resetRecording(...) and
83     *  finishRecording() calls.  The latter call returns a DisplayList that is specific to the
84     *  RenderPipeline defined by Properties::getRenderPipelineType().
85     *
86     *  @param width of the requested Canvas.
87     *  @param height of the requested Canvas.
88     *  @param renderNode is an optional parameter that specifies the node that will consume the
89     *      DisplayList produced by the returned Canvas.  This enables the reuse of select C++
90     *      objects as a speed optimization.
91     *  @return new non-null Canvas Object.  The type of DisplayList produced by this canvas is
92            determined based on Properties::getRenderPipelineType().
93     *
94     */
95    static WARN_UNUSED_RESULT Canvas* create_recording_canvas(int width, int height,
96            uirenderer::RenderNode* renderNode = nullptr);
97
98    enum class XformToSRGB {
99        // Transform any Bitmaps to the sRGB color space before drawing.
100        kImmediate,
101
102        // Draw the Bitmap as is.  This likely means that we are recording and that the
103        // transform can be handled at playback time.
104        kDefer,
105    };
106
107    /**
108     *  Create a new Canvas object which delegates to an SkCanvas.
109     *
110     *  @param skiaCanvas Must not be NULL. All drawing calls will be
111     *      delegated to this object. This function will call ref() on the
112     *      SkCanvas, and the returned Canvas will unref() it upon
113     *      destruction.
114     *  @param xformToSRGB Indicates if bitmaps should be xformed to the sRGB
115     *      color space before drawing.
116     *  @return new non-null Canvas Object.  The type of DisplayList produced by this canvas is
117     *      determined based on  Properties::getRenderPipelineType().
118     */
119    static Canvas* create_canvas(SkCanvas* skiaCanvas, XformToSRGB xformToSRGB);
120
121    /**
122     *  Provides a Skia SkCanvas interface that acts as a proxy to this Canvas.
123     *  It is useful for testing and clients (e.g. Picture/Movie) that expect to
124     *  draw their contents into an SkCanvas.
125     *
126     *  The SkCanvas returned is *only* valid until another Canvas call is made
127     *  that would change state (e.g. matrix or clip). Clients of asSkCanvas()
128     *  are responsible for *not* persisting this pointer.
129     *
130     *  Further, the returned SkCanvas should NOT be unref'd and is valid until
131     *  this canvas is destroyed or a new bitmap is set.
132     */
133    virtual SkCanvas* asSkCanvas() = 0;
134
135
136    virtual void setBitmap(const SkBitmap& bitmap) = 0;
137
138    virtual bool isOpaque() = 0;
139    virtual int width() = 0;
140    virtual int height() = 0;
141
142// ----------------------------------------------------------------------------
143// View System operations (not exposed in public Canvas API)
144// ----------------------------------------------------------------------------
145
146    virtual void resetRecording(int width, int height,
147            uirenderer::RenderNode* renderNode = nullptr) = 0;
148    virtual uirenderer::DisplayList* finishRecording() = 0;
149    virtual void insertReorderBarrier(bool enableReorder) = 0;
150
151    virtual void setHighContrastText(bool highContrastText) = 0;
152    virtual bool isHighContrastText() = 0;
153
154    virtual void drawRoundRect(uirenderer::CanvasPropertyPrimitive* left,
155            uirenderer::CanvasPropertyPrimitive* top, uirenderer::CanvasPropertyPrimitive* right,
156            uirenderer::CanvasPropertyPrimitive* bottom, uirenderer::CanvasPropertyPrimitive* rx,
157            uirenderer::CanvasPropertyPrimitive* ry, uirenderer::CanvasPropertyPaint* paint) = 0;
158    virtual void drawCircle(uirenderer::CanvasPropertyPrimitive* x,
159            uirenderer::CanvasPropertyPrimitive* y, uirenderer::CanvasPropertyPrimitive* radius,
160            uirenderer::CanvasPropertyPaint* paint) = 0;
161
162    virtual void drawLayer(uirenderer::DeferredLayerUpdater* layerHandle) = 0;
163    virtual void drawRenderNode(uirenderer::RenderNode* renderNode) = 0;
164    virtual void callDrawGLFunction(Functor* functor,
165            uirenderer::GlFunctorLifecycleListener* listener) = 0;
166
167// ----------------------------------------------------------------------------
168// Canvas state operations
169// ----------------------------------------------------------------------------
170
171    // Save (layer)
172    virtual int getSaveCount() const = 0;
173    virtual int save(SaveFlags::Flags flags) = 0;
174    virtual void restore() = 0;
175    virtual void restoreToCount(int saveCount) = 0;
176
177    virtual int saveLayer(float left, float top, float right, float bottom,
178                const SkPaint* paint, SaveFlags::Flags flags) = 0;
179    virtual int saveLayerAlpha(float left, float top, float right, float bottom,
180            int alpha, SaveFlags::Flags flags) = 0;
181
182    // Matrix
183    virtual void getMatrix(SkMatrix* outMatrix) const = 0;
184    virtual void setMatrix(const SkMatrix& matrix) = 0;
185
186    virtual void concat(const SkMatrix& matrix) = 0;
187    virtual void rotate(float degrees) = 0;
188    virtual void scale(float sx, float sy) = 0;
189    virtual void skew(float sx, float sy) = 0;
190    virtual void translate(float dx, float dy) = 0;
191
192    // clip
193    virtual bool getClipBounds(SkRect* outRect) const = 0;
194    virtual bool quickRejectRect(float left, float top, float right, float bottom) const = 0;
195    virtual bool quickRejectPath(const SkPath& path) const = 0;
196
197    virtual bool clipRect(float left, float top, float right, float bottom,
198            SkClipOp op) = 0;
199    virtual bool clipPath(const SkPath* path, SkClipOp op) = 0;
200
201    // filters
202    virtual SkDrawFilter* getDrawFilter() = 0;
203    virtual void setDrawFilter(SkDrawFilter* drawFilter) = 0;
204
205    // WebView only
206    virtual SkCanvasState* captureCanvasState() const { return nullptr; }
207
208// ----------------------------------------------------------------------------
209// Canvas draw operations
210// ----------------------------------------------------------------------------
211    virtual void drawColor(int color, SkBlendMode mode) = 0;
212    virtual void drawPaint(const SkPaint& paint) = 0;
213
214    // Geometry
215    virtual void drawPoint(float x, float y, const SkPaint& paint) = 0;
216    virtual void drawPoints(const float* points, int floatCount, const SkPaint& paint) = 0;
217    virtual void drawLine(float startX, float startY, float stopX, float stopY,
218                const SkPaint& paint) = 0;
219    virtual void drawLines(const float* points, int floatCount, const SkPaint& paint) = 0;
220    virtual void drawRect(float left, float top, float right, float bottom,
221            const SkPaint& paint) = 0;
222    virtual void drawRegion(const SkRegion& region, const SkPaint& paint) = 0;
223    virtual void drawRoundRect(float left, float top, float right, float bottom,
224            float rx, float ry, const SkPaint& paint) = 0;
225    virtual void drawCircle(float x, float y, float radius, const SkPaint& paint) = 0;
226    virtual void drawOval(float left, float top, float right, float bottom,
227            const SkPaint& paint) = 0;
228    virtual void drawArc(float left, float top, float right, float bottom,
229            float startAngle, float sweepAngle, bool useCenter, const SkPaint& paint) = 0;
230    virtual void drawPath(const SkPath& path, const SkPaint& paint) = 0;
231    virtual void drawVertices(SkCanvas::VertexMode vertexMode, int vertexCount,
232                              const float* verts, const float* tex, const int* colors,
233                              const uint16_t* indices, int indexCount, const SkPaint& paint) = 0;
234
235    // Bitmap-based
236    virtual void drawBitmap(Bitmap& bitmap, float left, float top,
237            const SkPaint* paint) = 0;
238    virtual void drawBitmap(Bitmap& bitmap, const SkMatrix& matrix,
239            const SkPaint* paint) = 0;
240    virtual void drawBitmap(Bitmap& bitmap, float srcLeft, float srcTop,
241            float srcRight, float srcBottom, float dstLeft, float dstTop,
242            float dstRight, float dstBottom, const SkPaint* paint) = 0;
243    virtual void drawBitmapMesh(Bitmap& bitmap, int meshWidth, int meshHeight,
244            const float* vertices, const int* colors, const SkPaint* paint) = 0;
245    virtual void drawNinePatch(Bitmap& bitmap, const android::Res_png_9patch& chunk,
246            float dstLeft, float dstTop, float dstRight, float dstBottom,
247            const SkPaint* paint) = 0;
248
249    /**
250     * Specifies if the positions passed to ::drawText are absolute or relative
251     * to the (x,y) value provided.
252     *
253     * If true the (x,y) values are ignored. Otherwise, those (x,y) values need
254     * to be added to each glyph's position to get its absolute position.
255     */
256    virtual bool drawTextAbsolutePos() const = 0;
257
258    /**
259     * Draws a VectorDrawable onto the canvas.
260     */
261    virtual void drawVectorDrawable(VectorDrawableRoot* tree) = 0;
262
263    /**
264     * Converts utf16 text to glyphs, calculating position and boundary,
265     * and delegating the final draw to virtual drawGlyphs method.
266     */
267    void drawText(const uint16_t* text, int start, int count, int contextCount,
268            float x, float y, int bidiFlags, const Paint& origPaint, Typeface* typeface);
269
270    void drawTextOnPath(const uint16_t* text, int count, int bidiFlags, const SkPath& path,
271            float hOffset, float vOffset, const Paint& paint, Typeface* typeface);
272
273protected:
274    void drawTextDecorations(float x, float y, float length, const SkPaint& paint);
275
276    /**
277     * drawText: count is of glyphs
278     * totalAdvance: used to define width of text decorations (underlines, strikethroughs).
279     */
280    virtual void drawGlyphs(const uint16_t* glyphs, const float* positions, int count,
281            const SkPaint& paint, float x, float y,
282            float boundsLeft, float boundsTop, float boundsRight, float boundsBottom,
283            float totalAdvance) = 0;
284    virtual void drawLayoutOnPath(const minikin::Layout& layout, float hOffset, float vOffset,
285            const SkPaint& paint, const SkPath& path, size_t start, size_t end) = 0;
286    friend class DrawTextFunctor;
287    friend class DrawTextOnPathFunctor;
288    friend class uirenderer::SkiaCanvasProxy;
289};
290
291}; // namespace android
292