Canvas.h revision acb4099deff72c2c631f7110a405a3331d3e8b27 
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#ifndef ANDROID_GRAPHICS_CANVAS_H
18#define ANDROID_GRAPHICS_CANVAS_H
19
20#include "SkBitmap.h"
21#include "SkCanvas.h"
22#include "SkMatrix.h"
23
24namespace android {
25
26class Canvas {
27public:
28    virtual ~Canvas() {};
29
30    static Canvas* create_canvas(SkBitmap* bitmap);
31    static Canvas* create_canvas(SkCanvas* skiaCanvas);
32
33    // TODO: enable HWUI to either create similar canvas wrapper or subclass
34    //       directly from Canvas
35    //static Canvas* create_canvas(uirenderer::Renderer* renderer);
36
37    // TODO: this is a temporary affordance until all necessary logic can be
38    //       moved within this interface! Further, the return value should
39    //       NOT be unref'd and is valid until this canvas is destroyed or a
40    //       new bitmap is set.
41    virtual SkCanvas* getSkCanvas() = 0;
42
43    virtual void setBitmap(SkBitmap* bitmap, bool copyState) = 0;
44
45    virtual bool isOpaque() = 0;
46    virtual int width() = 0;
47    virtual int height() = 0;
48
49// ----------------------------------------------------------------------------
50// Canvas state operations
51// ----------------------------------------------------------------------------
52    // Save (layer)
53    virtual int getSaveCount() const = 0;
54    virtual int save(SkCanvas::SaveFlags flags) = 0;
55    virtual void restore() = 0;
56    virtual void restoreToCount(int saveCount) = 0;
57
58    virtual int saveLayer(float left, float top, float right, float bottom,
59                const SkPaint* paint, SkCanvas::SaveFlags flags) = 0;
60    virtual int saveLayerAlpha(float left, float top, float right, float bottom,
61            int alpha, SkCanvas::SaveFlags flags) = 0;
62
63    // Matrix
64    virtual void getMatrix(SkMatrix* outMatrix) const = 0;
65    virtual void setMatrix(const SkMatrix& matrix) = 0;
66
67    virtual void concat(const SkMatrix& matrix) = 0;
68    virtual void rotate(float degrees) = 0;
69    virtual void scale(float sx, float sy) = 0;
70    virtual void skew(float sx, float sy) = 0;
71    virtual void translate(float dx, float dy) = 0;
72
73    // clip
74    virtual bool getClipBounds(SkRect* outRect) const = 0;
75    virtual bool quickRejectRect(float left, float top, float right, float bottom) const = 0;
76    virtual bool quickRejectPath(const SkPath& path) const = 0;
77
78    virtual bool clipRect(float left, float top, float right, float bottom, SkRegion::Op op) = 0;
79    virtual bool clipPath(const SkPath* path, SkRegion::Op op) = 0;
80    virtual bool clipRegion(const SkRegion* region, SkRegion::Op op) = 0;
81
82    // filters
83    virtual SkDrawFilter* getDrawFilter() = 0;
84    virtual void setDrawFilter(SkDrawFilter* drawFilter) = 0;
85
86// ----------------------------------------------------------------------------
87// Canvas draw operations
88// ----------------------------------------------------------------------------
89    virtual void drawColor(int color, SkXfermode::Mode mode) = 0;
90    virtual void drawPaint(const SkPaint& paint) = 0;
91
92    // Geometry
93    virtual void drawPoint(float x, float y, const SkPaint& paint) = 0;
94    virtual void drawPoints(const float* points, int count, const SkPaint& paint) = 0;
95    virtual void drawLine(float startX, float startY, float stopX, float stopY,
96                const SkPaint& paint) = 0;
97    virtual void drawLines(const float* points, int count, const SkPaint& paint) = 0;
98    virtual void drawRect(float left, float top, float right, float bottom,
99            const SkPaint& paint) = 0;
100    virtual void drawRoundRect(float left, float top, float right, float bottom,
101            float rx, float ry, const SkPaint& paint) = 0;
102    virtual void drawCircle(float x, float y, float radius, const SkPaint& paint) = 0;
103    virtual void drawOval(float left, float top, float right, float bottom,
104            const SkPaint& paint) = 0;
105    virtual void drawArc(float left, float top, float right, float bottom,
106            float startAngle, float sweepAngle, bool useCenter, const SkPaint& paint) = 0;
107    virtual void drawPath(const SkPath& path, const SkPaint& paint) = 0;
108    virtual void drawVertices(SkCanvas::VertexMode vertexMode, int vertexCount,
109                              const float* verts, const float* tex, const int* colors,
110                              const uint16_t* indices, int indexCount, const SkPaint& paint) = 0;
111
112    // Bitmap-based
113    virtual void drawBitmap(const SkBitmap& bitmap, float left, float top,
114            const SkPaint* paint) = 0;
115    virtual void drawBitmap(const SkBitmap& bitmap, const SkMatrix& matrix,
116            const SkPaint* paint) = 0;
117    virtual void drawBitmap(const SkBitmap& bitmap, float srcLeft, float srcTop,
118            float srcRight, float srcBottom, float dstLeft, float dstTop,
119            float dstRight, float dstBottom, const SkPaint* paint) = 0;
120    virtual void drawBitmapMesh(const SkBitmap& bitmap, int meshWidth, int meshHeight,
121            const float* vertices, const int* colors, const SkPaint* paint) = 0;
122
123    // Text
124    virtual void drawText(const uint16_t* text, const float* positions, int count,
125            const SkPaint& paint, float x, float y,
126            float boundsLeft, float boundsTop, float boundsRight, float boundsBottom) = 0;
127    virtual void drawPosText(const uint16_t* text, const float* positions, int count,
128            int posCount, const SkPaint& paint) = 0;
129    virtual void drawTextOnPath(const uint16_t* glyphs, int count, const SkPath& path,
130            float hOffset, float vOffset, const SkPaint& paint) = 0;
131
132    /*
133     * Specifies if the positions passed to ::drawText are absolute or relative
134     * to the (x,y) value provided.
135     *
136     * If true the (x,y) values are ignored. Otherwise, those (x,y) values need
137     * to be added to each glyph's position to get its absolute position.
138     */
139    virtual bool drawTextAbsolutePos() const = 0;
140};
141
142}; // namespace android
143#endif // ANDROID_GRAPHICS_CANVAS_H
144