gfx/thebes/cairo-xlib-utils.h@97036ab72558 (annotated)
gfx/thebes/cairo-xlib-utils.h
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- |
| michael@0 | 2 | * This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 3 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 4 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 5 | |
| michael@0 | 6 | #ifndef CAIROXLIBUTILS_H_ |
| michael@0 | 7 | #define CAIROXLIBUTILS_H_ |
| michael@0 | 8 | |
| michael@0 | 9 | #include "cairo.h" |
| michael@0 | 10 | #include <X11/Xlib.h> |
| michael@0 | 11 | |
| michael@0 | 12 | CAIRO_BEGIN_DECLS |
| michael@0 | 13 | |
| michael@0 | 14 | /** |
| michael@0 | 15 | * This callback encapsulates Xlib-based rendering. We assume that the |
| michael@0 | 16 | * execution of the callback is equivalent to compositing some RGBA image of |
| michael@0 | 17 | * size (bounds_width, bounds_height) onto the drawable at offset (offset_x, |
| michael@0 | 18 | * offset_y), clipped to the union of the clip_rects if num_rects is greater |
| michael@0 | 19 | * than zero. This includes the assumption that the same RGBA image |
| michael@0 | 20 | * is composited if you call the callback multiple times with the same closure, |
| michael@0 | 21 | * display and visual during a single cairo_draw_with_xlib call. |
| michael@0 | 22 | * |
| michael@0 | 23 | * @return True on success, False on non-recoverable error |
| michael@0 | 24 | */ |
| michael@0 | 25 | typedef cairo_bool_t (* cairo_xlib_drawing_callback) |
| michael@0 | 26 | (void *closure, |
| michael@0 | 27 | Screen *screen, |
| michael@0 | 28 | Drawable drawable, |
| michael@0 | 29 | Visual *visual, |
| michael@0 | 30 | short offset_x, short offset_y, |
| michael@0 | 31 | XRectangle* clip_rects, unsigned int num_rects); |
| michael@0 | 32 | |
| michael@0 | 33 | /** |
| michael@0 | 34 | * This structure captures the result of the native drawing, in case the |
| michael@0 | 35 | * caller may wish to reapply the drawing efficiently later. |
| michael@0 | 36 | */ |
| michael@0 | 37 | typedef struct { |
| michael@0 | 38 | cairo_surface_t *surface; |
| michael@0 | 39 | cairo_bool_t uniform_alpha; |
| michael@0 | 40 | cairo_bool_t uniform_color; |
| michael@0 | 41 | double alpha; /* valid only if uniform_alpha is TRUE */ |
| michael@0 | 42 | double r, g, b; /* valid only if uniform_color is TRUE */ |
| michael@0 | 43 | } cairo_xlib_drawing_result_t; |
| michael@0 | 44 | |
| michael@0 | 45 | /** |
| michael@0 | 46 | * This type specifies whether the native drawing callback draws all pixels |
| michael@0 | 47 | * in its bounds opaquely, independent of the contents of the target drawable, |
| michael@0 | 48 | * or whether it leaves pixels transparent/translucent or depends on the |
| michael@0 | 49 | * existing contents of the target drawable in some way. |
| michael@0 | 50 | */ |
| michael@0 | 51 | typedef enum _cairo_xlib_drawing_opacity { |
| michael@0 | 52 | CAIRO_XLIB_DRAWING_OPAQUE, |
| michael@0 | 53 | CAIRO_XLIB_DRAWING_TRANSPARENT |
| michael@0 | 54 | } cairo_xlib_drawing_opacity_t; |
| michael@0 | 55 | |
| michael@0 | 56 | /** |
| michael@0 | 57 | * This type encodes the capabilities of the native drawing callback. |
| michael@0 | 58 | * |
| michael@0 | 59 | * If CAIRO_XLIB_DRAWING_SUPPORTS_OFFSET is set, 'offset_x' and 'offset_y' |
| michael@0 | 60 | * can be nonzero in the call to the callback; otherwise they will be zero. |
| michael@0 | 61 | * |
| michael@0 | 62 | * If CAIRO_XLIB_DRAWING_SUPPORTS_CLIP_RECT is set, then 'num_rects' can be |
| michael@0 | 63 | * zero or one in the call to the callback. If |
| michael@0 | 64 | * CAIRO_XLIB_DRAWING_SUPPORTS_CLIP_LIST is set, then 'num_rects' can be |
| michael@0 | 65 | * anything in the call to the callback. Otherwise 'num_rects' will be zero. |
| michael@0 | 66 | * Do not set both of these values. |
| michael@0 | 67 | * |
| michael@0 | 68 | * If CAIRO_XLIB_DRAWING_SUPPORTS_ALTERNATE_SCREEN is set, then 'screen' can |
| michael@0 | 69 | * be any screen on any display, otherwise it will be the default screen of |
| michael@0 | 70 | * the display passed into cairo_draw_with_xlib. |
| michael@0 | 71 | * |
| michael@0 | 72 | * If CAIRO_XLIB_DRAWING_SUPPORTS_NONDEFAULT_VISUAL is set, then 'visual' can be |
| michael@0 | 73 | * any visual, otherwise it will be equal to |
| michael@0 | 74 | * DefaultVisualOfScreen (screen). |
| michael@0 | 75 | */ |
| michael@0 | 76 | typedef enum { |
| michael@0 | 77 | CAIRO_XLIB_DRAWING_SUPPORTS_OFFSET = 0x01, |
| michael@0 | 78 | CAIRO_XLIB_DRAWING_SUPPORTS_CLIP_RECT = 0x02, |
| michael@0 | 79 | CAIRO_XLIB_DRAWING_SUPPORTS_CLIP_LIST = 0x04, |
| michael@0 | 80 | CAIRO_XLIB_DRAWING_SUPPORTS_ALTERNATE_SCREEN = 0x08, |
| michael@0 | 81 | CAIRO_XLIB_DRAWING_SUPPORTS_NONDEFAULT_VISUAL = 0x10 |
| michael@0 | 82 | } cairo_xlib_drawing_support_t; |
| michael@0 | 83 | |
| michael@0 | 84 | /** |
| michael@0 | 85 | * Draw Xlib output into any cairo context. All cairo transforms and effects |
| michael@0 | 86 | * are honored, including the current operator. This is equivalent to a |
| michael@0 | 87 | * cairo_set_source_surface and then cairo_paint. |
| michael@0 | 88 | * @param cr the context to draw into |
| michael@0 | 89 | * @param callback the code to perform Xlib rendering |
| michael@0 | 90 | * @param closure associated data |
| michael@0 | 91 | * @param dpy an X display to use in case the cairo context has no associated X display |
| michael@0 | 92 | * @param width the width of the putative image drawn by the callback |
| michael@0 | 93 | * @param height the height of the putative image drawn by the callback |
| michael@0 | 94 | * @param is_opaque set to CAIRO_XLIB_DRAWING_IS_OPAQUE to indicate |
| michael@0 | 95 | * that all alpha values of the putative image will be 1.0; the pixels drawn into |
| michael@0 | 96 | * the Drawable must not depend on the prior contents of the Drawable |
| michael@0 | 97 | * in any way |
| michael@0 | 98 | * @param capabilities the capabilities of the callback as described above. |
| michael@0 | 99 | * @param result if non-NULL, we *may* fill in the struct with information about |
| michael@0 | 100 | * the rendered image. 'surface' may be filled in with a surface representing |
| michael@0 | 101 | * the image, similar to the target of 'cr'. If 'uniform_alpha' is True then |
| michael@0 | 102 | * every pixel of the image has the same alpha value 'alpha'. If |
| michael@0 | 103 | * 'uniform_color' is True then every pixel of the image has the same RGB |
| michael@0 | 104 | * color (r, g, b). If the image has uniform color and alpha (or alpha is zero, |
| michael@0 | 105 | * in which case the color is always uniform) then we won't bother returning |
| michael@0 | 106 | * a surface for it. |
| michael@0 | 107 | */ |
| michael@0 | 108 | void cairo_draw_with_xlib (cairo_t *cr, |
| michael@0 | 109 | cairo_xlib_drawing_callback callback, |
| michael@0 | 110 | void *closure, |
| michael@0 | 111 | Display *dpy, |
| michael@0 | 112 | unsigned int width, unsigned int height, |
| michael@0 | 113 | cairo_xlib_drawing_opacity_t is_opaque, |
| michael@0 | 114 | cairo_xlib_drawing_support_t capabilities, |
| michael@0 | 115 | cairo_xlib_drawing_result_t *result); |
| michael@0 | 116 | |
| michael@0 | 117 | CAIRO_END_DECLS |
| michael@0 | 118 | |
| michael@0 | 119 | #endif /*CAIROXLIBUTILS_H_*/ |
