summaryrefslogtreecommitdiffstats
path: root/dom/webidl/CanvasRenderingContext2D.webidl
blob: 38a30f9e39eef43634ed06b77e1bd3cb23d2013c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * The origin of this IDL file is
 * http://www.whatwg.org/specs/web-apps/current-work/
 *
 * © Copyright 2004-2011 Apple Computer, Inc., Mozilla Foundation, and
 * Opera Software ASA. You are granted a license to use, reproduce
 * and create derivative works of this document.
 */

enum CanvasWindingRule { "nonzero", "evenodd" };

dictionary ContextAttributes2D {
  // whether or not we're planning to do a lot of readback operations
  boolean willReadFrequently = false;
  // signal if the canvas contains an alpha channel
  boolean alpha = true;
};

dictionary HitRegionOptions {
  Path2D? path = null;
  DOMString id = "";
  Element? control = null;
};

typedef (HTMLImageElement or
         HTMLCanvasElement or
         HTMLVideoElement or
         ImageBitmap) CanvasImageSource;

interface CanvasRenderingContext2D {

  // back-reference to the canvas.  Might be null if we're not
  // associated with a canvas.
  readonly attribute HTMLCanvasElement? canvas;

  // state
  void save(); // push state on state stack
  void restore(); // pop state stack and restore state

  // transformations (default transform is the identity matrix)
// NOT IMPLEMENTED           attribute SVGMatrix currentTransform;
  [Throws, LenientFloat]
  void scale(double x, double y);
  [Throws, LenientFloat]
  void rotate(double angle);
  [Throws, LenientFloat]
  void translate(double x, double y);
  [Throws, LenientFloat]
  void transform(double a, double b, double c, double d, double e, double f);
  [Throws, LenientFloat]
  void setTransform(double a, double b, double c, double d, double e, double f);
  [Throws]
  void resetTransform();

  // compositing
           attribute unrestricted double globalAlpha; // (default 1.0)
           [Throws]
           attribute DOMString globalCompositeOperation; // (default source-over)

  // colors and styles (see also the CanvasDrawingStyles interface)
           attribute (DOMString or CanvasGradient or CanvasPattern) strokeStyle; // (default black)
           attribute (DOMString or CanvasGradient or CanvasPattern) fillStyle; // (default black)
  [NewObject]
  CanvasGradient createLinearGradient(double x0, double y0, double x1, double y1);
  [NewObject, Throws]
  CanvasGradient createRadialGradient(double x0, double y0, double r0, double x1, double y1, double r1);
  [NewObject, Throws]
  CanvasPattern? createPattern(CanvasImageSource image, [TreatNullAs=EmptyString] DOMString repetition);

  // shadows
           [LenientFloat]
           attribute double shadowOffsetX; // (default 0)
           [LenientFloat]
           attribute double shadowOffsetY; // (default 0)
           [LenientFloat]
           attribute double shadowBlur; // (default 0)
           attribute DOMString shadowColor; // (default transparent black)

  [Pref="canvas.filters.enabled", SetterThrows]
  attribute DOMString filter; // (default empty string = no filter)

  // rects
  [LenientFloat]
  void clearRect(double x, double y, double w, double h);
  [LenientFloat]
  void fillRect(double x, double y, double w, double h);
  [LenientFloat]
  void strokeRect(double x, double y, double w, double h);

  // path API (see also CanvasPathMethods)
  void beginPath();
  void fill(optional CanvasWindingRule winding = "nonzero");
  void fill(Path2D path, optional CanvasWindingRule winding = "nonzero");
  void stroke();
  void stroke(Path2D path);
  [Pref="canvas.focusring.enabled", Throws] void drawFocusIfNeeded(Element element);
// NOT IMPLEMENTED  void drawSystemFocusRing(Path path, HTMLElement element);
  [Pref="canvas.customfocusring.enabled"] boolean drawCustomFocusRing(Element element);
// NOT IMPLEMENTED  boolean drawCustomFocusRing(Path path, HTMLElement element);
// NOT IMPLEMENTED  void scrollPathIntoView();
// NOT IMPLEMENTED  void scrollPathIntoView(Path path);
  void clip(optional CanvasWindingRule winding = "nonzero");
  void clip(Path2D path, optional CanvasWindingRule winding = "nonzero");
// NOT IMPLEMENTED  void resetClip();
  boolean isPointInPath(unrestricted double x, unrestricted double y, optional CanvasWindingRule winding = "nonzero");
  boolean isPointInPath(Path2D path, unrestricted double x, unrestricted double y, optional CanvasWindingRule winding = "nonzero");
  boolean isPointInStroke(double x, double y);
  boolean isPointInStroke(Path2D path, unrestricted double x, unrestricted double y);

  // text (see also the CanvasDrawingStyles interface)
  [Throws, LenientFloat]
  void fillText(DOMString text, double x, double y, optional double maxWidth);
  [Throws, LenientFloat]
  void strokeText(DOMString text, double x, double y, optional double maxWidth);
  [NewObject, Throws]
  TextMetrics measureText(DOMString text);

  // drawing images
  attribute boolean imageSmoothingEnabled;

  [Throws, LenientFloat]
  void drawImage(CanvasImageSource image, double dx, double dy);
  [Throws, LenientFloat]
  void drawImage(CanvasImageSource image, double dx, double dy, double dw, double dh);
  [Throws, LenientFloat]
  void drawImage(CanvasImageSource image, double sx, double sy, double sw, double sh, double dx, double dy, double dw, double dh);

  // hit regions
  [Pref="canvas.hitregions.enabled", Throws] void addHitRegion(optional HitRegionOptions options);
  [Pref="canvas.hitregions.enabled"] void removeHitRegion(DOMString id);
  [Pref="canvas.hitregions.enabled"] void clearHitRegions();

  // pixel manipulation
  [NewObject, Throws]
  ImageData createImageData(double sw, double sh);
  [NewObject, Throws]
  ImageData createImageData(ImageData imagedata);
  [NewObject, Throws]
  ImageData getImageData(double sx, double sy, double sw, double sh);
  [Throws]
  void putImageData(ImageData imagedata, double dx, double dy);
  [Throws]
  void putImageData(ImageData imagedata, double dx, double dy, double dirtyX, double dirtyY, double dirtyWidth, double dirtyHeight);

  // Mozilla-specific stuff
  // FIXME Bug 768048 mozCurrentTransform/mozCurrentTransformInverse should return a WebIDL array.
  [Throws]
  attribute object mozCurrentTransform; // [ m11, m12, m21, m22, dx, dy ], i.e. row major
  [Throws]
  attribute object mozCurrentTransformInverse;

  [SetterThrows]
  attribute DOMString mozTextStyle;

  // image smoothing mode -- if disabled, images won't be smoothed
  // if scaled.
  [Deprecated="PrefixedImageSmoothingEnabled"]
  attribute boolean mozImageSmoothingEnabled;

  // Show the caret if appropriate when drawing
  [ChromeOnly]
  const unsigned long DRAWWINDOW_DRAW_CARET   = 0x01;
  // Don't flush pending layout notifications that could otherwise
  // be batched up
  [ChromeOnly]
  const unsigned long DRAWWINDOW_DO_NOT_FLUSH = 0x02;
  // Draw scrollbars and scroll the viewport if they are present
  [ChromeOnly]
  const unsigned long DRAWWINDOW_DRAW_VIEW    = 0x04;
  // Use the widget layer manager if available. This means hardware
  // acceleration may be used, but it might actually be slower or
  // lower quality than normal. It will however more accurately reflect
  // the pixels rendered to the screen.
  [ChromeOnly]
  const unsigned long DRAWWINDOW_USE_WIDGET_LAYERS = 0x08;
  // Don't synchronously decode images - draw what we have
  [ChromeOnly]
  const unsigned long DRAWWINDOW_ASYNC_DECODE_IMAGES = 0x10;

  /**
   * Renders a region of a window into the canvas.  The contents of
   * the window's viewport are rendered, ignoring viewport clipping
   * and scrolling.
   *
   * @param x
   * @param y
   * @param w
   * @param h specify the area of the window to render, in CSS
   * pixels.
   *
   * @param backgroundColor the canvas is filled with this color
   * before we render the window into it. This color may be
   * transparent/translucent. It is given as a CSS color string
   * (e.g., rgb() or rgba()).
   *
   * @param flags Used to better control the drawWindow call.
   * Flags can be ORed together.
   *
   * Of course, the rendering obeys the current scale, transform and
   * globalAlpha values.
   *
   * Hints:
   * -- If 'rgba(0,0,0,0)' is used for the background color, the
   * drawing will be transparent wherever the window is transparent.
   * -- Top-level browsed documents are usually not transparent
   * because the user's background-color preference is applied,
   * but IFRAMEs are transparent if the page doesn't set a background.
   * -- If an opaque color is used for the background color, rendering
   * will be faster because we won't have to compute the window's
   * transparency.
   *
   * This API cannot currently be used by Web content. It is chrome
   * only.
   */
  [Throws, ChromeOnly]
  void drawWindow(Window window, double x, double y, double w, double h,
                  DOMString bgColor, optional unsigned long flags = 0);
  [Throws, ChromeOnly]
  void asyncDrawXULElement(XULElement elem, double x, double y, double w,
                           double h, DOMString bgColor,
                           optional unsigned long flags = 0);

  /**
   * This causes a context that is currently using a hardware-accelerated
   * backend to fallback to a software one. All state should be preserved.
   */
  [ChromeOnly]
  void demote();
};
CanvasRenderingContext2D implements CanvasDrawingStyles;
CanvasRenderingContext2D implements CanvasPathMethods;

[NoInterfaceObject]
interface CanvasDrawingStyles {
  // line caps/joins
           [LenientFloat]
           attribute double lineWidth; // (default 1)
           attribute DOMString lineCap; // "butt", "round", "square" (default "butt")
           [GetterThrows]
           attribute DOMString lineJoin; // "round", "bevel", "miter" (default "miter")
           [LenientFloat]
           attribute double miterLimit; // (default 10)

  // dashed lines
    [LenientFloat, Throws] void setLineDash(sequence<double> segments); // default empty
    sequence<double> getLineDash();
    [LenientFloat] attribute double lineDashOffset;

  // text
           [SetterThrows]
           attribute DOMString font; // (default 10px sans-serif)
           attribute DOMString textAlign; // "start", "end", "left", "right", "center" (default: "start")
           attribute DOMString textBaseline; // "top", "hanging", "middle", "alphabetic", "ideographic", "bottom" (default: "alphabetic")
};

[NoInterfaceObject]
interface CanvasPathMethods {
  // shared path API methods
  void closePath();
  [LenientFloat]
  void moveTo(double x, double y);
  [LenientFloat]
  void lineTo(double x, double y);
  [LenientFloat]
  void quadraticCurveTo(double cpx, double cpy, double x, double y);

  [LenientFloat]
  void bezierCurveTo(double cp1x, double cp1y, double cp2x, double cp2y, double x, double y);

  [Throws, LenientFloat]
  void arcTo(double x1, double y1, double x2, double y2, double radius); 
// NOT IMPLEMENTED  [LenientFloat] void arcTo(double x1, double y1, double x2, double y2, double radiusX, double radiusY, double rotation);

  [LenientFloat]
  void rect(double x, double y, double w, double h);

  [Throws, LenientFloat]
  void arc(double x, double y, double radius, double startAngle, double endAngle, optional boolean anticlockwise = false); 

  [Throws, LenientFloat]
  void ellipse(double x, double y, double radiusX, double radiusY, double rotation, double startAngle, double endAngle, optional boolean anticlockwise = false);
};

interface CanvasGradient {
  // opaque object
  [Throws]
  // addColorStop should take a double
  void addColorStop(float offset, DOMString color);
};

interface CanvasPattern {
  // opaque object
  // [Throws, LenientFloat] - could not do this overload because of bug 1020975
  // void setTransform(double a, double b, double c, double d, double e, double f);

  // No throw necessary here - SVGMatrix is always good.
  void setTransform(SVGMatrix matrix);
};

interface TextMetrics {

  // x-direction
  readonly attribute double width; // advance width

  /*
   * NOT IMPLEMENTED YET

  readonly attribute double actualBoundingBoxLeft;
  readonly attribute double actualBoundingBoxRight;

  // y-direction
  readonly attribute double fontBoundingBoxAscent;
  readonly attribute double fontBoundingBoxDescent;
  readonly attribute double actualBoundingBoxAscent;
  readonly attribute double actualBoundingBoxDescent;
  readonly attribute double emHeightAscent;
  readonly attribute double emHeightDescent;
  readonly attribute double hangingBaseline;
  readonly attribute double alphabeticBaseline;
  readonly attribute double ideographicBaseline;
  */

};

[Pref="canvas.path.enabled",
 Constructor,
 Constructor(Path2D other),
 Constructor(DOMString pathString)]
interface Path2D
{
  void addPath(Path2D path, optional SVGMatrix transformation);
};
Path2D implements CanvasPathMethods;