1mX Nonrectangular Window0m 1mShape Extension Protocol0m Version 1.1 X Consortium Standard X Version 11, Release 6.4 Keith Packard MIT X Consortium Intel Corporation Copyright © 1989 X Consortium Copyright © 2006 Keith Packard Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documenta- tion files (the ``Software''), to deal in the Software with- out restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the fol- lowing conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PUR- POSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. Except as contained in this notice, the name of the copy- right holders shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization from the copyright hold- ers. 1m1. Overview0m This extension provides arbitrary window and border shapes within the X11 protocol. The restriction of rectangular windows within the X protocol is a significant limitation in the implementation of many styles of user interface. For example, many transient win- dows would like to display a ``drop shadow'' to give the illusion of 3 dimensions. As another example, some user interface style guides call for buttons with rounded cor- ners; the full simulation of a nonrectangular shape, partic- ularly with respect to event distribution and cursor shape, is not possible within the core X protocol. As a final example, round clocks and nonrectangular icons are desirable visual addition to the desktop. This extension provides mechanisms for changing both the visible and interactive shape of a window to arbitrary, pos- sibly disjoint, nonrectangular forms. The intent of the extension is to supplement the existing semantics, not replace them. In particular, it is desirable for clients that are unaware of the extension to still be able to cope reasonably with shaped windows. For example, window man- agers should still be able to negotiate screen real estate in rectangular pieces. Toward this end, any shape specified for a window is clipped by the bounding rectangle for the window as specified by the window's geometry in the core protocol. An expected convention would be that client pro- grams expand their shape to fill the area offered by the window manager. 1m2. Description0m Each window (even with no shapes specified) is defined by three regions: the 4mbounding24m 4mregion24m, the 4mclip24m 4mregion24m and the 4minput24m 4mregion24m. The bounding region is the area of the parent window that the window will occupy (including border). The clip region is the subset of the bounding region that is available for subwindows and graphics. The area between the bounding region and the clip region is defined to be the border of the window. The input region is the subset of the bounding region that can ``contain'' the pointer. A nonshaped window will have a bounding region that is a rectangle spanning the window, including its border; the clip region will be a rectangle filling the inside dimen- sions (not including the border); the input region will match the bounding region. In this document, these areas are referred to as the 4mdefault24m 4mbounding24m 4mregion24m, the 4mdefault0m 4mclip24m 4mregion24m and the 4mdefault24m 4minput24m 4mregion24m. For a window with inside size of 4mwidth24m by 4mheight24m and border width 4mbwidth24m, the default bounding, clip and input regions are the rectangles (relative to the window origin): 1m10m X11 Nonrectangular Window Shape Extension Protocol __ | bounding.x = -4mbwidth0m bounding.y = -4mbwidth0m bounding.width = 4mwidth24m + 2 * 4mbwidth0m bounding.height = 4mheight24m + 2 * 4mbwidth0m clip.x = 0 clip.y = 0 clip.width = 4mwidth0m clip.height = 4mheight0m input.x = -4mbwidth0m input.y = -4mbwidth0m input.width = 4mwidth24m + 2 * 4mbwidth0m input.height = 4mheight24m + 2 * 4mbwidth0m |__ This extension allows a client to modify any combination of the bounding, clip or input regions by specifying new regions that combine with the default regions. These new regions are called the 4mclient24m 4mbounding24m 4mregion24m, the 4mclient0m 4mclip24m 4mregion24m and the 4mclient24m 4minput24m 4mregion24m. They are specified relative to the origin of the window and are always defined by offsets relative to the window origin (that is, region adjustments are not required when the window is moved). Three mechanisms for specifying regions are provided: a list of rectangles, a bitmap, and an existing bounding or clip region from a window. This is modeled on the specifi- cation of regions in graphics contexts in the core protocol and allows a variety of different uses of the extension. When using an existing window shape as an operand in speci- fying a new shape, the client region is used, unless none has been set, in which case the default region is used instead. The 4meffective24m 4mbounding24m 4mregion24m of a window is defined to be the intersection of the client bounding region with the default bounding region. Any portion of the client bounding region that is not included in the default bounding region will not be included in the effective bounding region on the screen. This means that window managers (or other geometry managers) used to dealing with rectangular client windows will be able to constrain the client to a rectangular area of the screen. Construction of the effective bounding region is dynamic; the client bounding region is not mutated to obtain the effective bounding region. If a client bounding region is specified that extends beyond the current default bounding region, and the window is later enlarged, the effective bounding region will be enlarged to include more of the 1m20m X11 Nonrectangular Window Shape Extension Protocol client bounding region. The 4meffective24m 4mclip24m 4mregion24m of a window is defined to be the intersection of the client clip region with both the default clip region and the client bounding region. Any portion of the client clip region that is not included in both the default clip region and the client bounding region will not be included in the effective clip region on the screen. Construction of the effective clip region is dynamic; the client clip region is not mutated to obtain the effective clip region. If a client clip region is specified that extends beyond the current default clip region and the win- dow or its bounding region is later enlarged, the effective clip region will be enlarged to include more of the client clip region if it is included in the effective bounding region. The border of a window is defined to be the difference between the effective bounding region and the effective clip region. If this region is empty, no border is displayed. If this region is nonempty, the border is filled using the border-tile or border-pixel of the window as specified in the core protocol. Note that a window with a nonzero border width will never be able to draw beyond the default clip region of the window. Also note that a zero border width does not prevent a window from having a border, since the clip shape can still be made smaller than the bounding shape. All output to the window and visible regions of any subwin- dows will be clipped to the effective clip region. The server must not retain window contents beyond the effective bounding region with backing store. The window's origin (for graphics operations, background tiling, and subwindow placement) is not affected by the existence of a bounding region or clip region. The 4meffective24m 4minput24m 4mregion24m of a window is defined to be the intersection of the client input region with both the default input region and the client bounding region. Any portion of the client input region that is not included in both the default input region and the client bounding region will not be included in the effective input region on the screen. Construction of the effective input region is dynamic; the client input region is not mutated to obtain the effective input region. If a client input region is specified that extends beyond the current default input region and the win- dow or its bounding region is later enlarged, the effective input region will be enlarged to include more of the client input region if it is included in the effective bounding region. 1m30m X11 Nonrectangular Window Shape Extension Protocol Areas that are inside the default bounding region but out- side the effective bounding region are not part of the win- dow; these areas of the screen will be occupied by other windows. Input events that occur within the default bound- ing region but outside the effective bounding region will be delivered as if the window was not occluding the event posi- tion. Events that occur in a nonrectangular border of a window will be delivered to that window, just as for events that occur in a normal rectangular border. An 4mInputOnly24m window can have its bounding or input region set, but it is a 4mMatch24m error to attempt to set a clip region on an 4mInputOnly24m window or to specify its clip region as a source to a request in this extension. The server must accept changes to the clip and input regions of a root window, but the server is permitted to ignore requested changes to the bounding region of a root window. If the server accepts bounding region changes, the contents of the screen outside the bounding region are implementation dependent. 1m3. Types0m The following types are used in the request and event defi- nitions in subsequent sections. SHAPE_KIND: {4mBounding24m, 4mClip24m, 4mInput24m} SHAPE_OP: {4mSet24m, 4mUnion24m, 4mIntersect24m, 4mSubtract24m, 4mInvert24m} 4mSet24m indicates that the region specified as an explicit source in the request is stored unaltered as the new desti- nation client region. 4mUnion24m indicates that the source and destination regions are unioned together to produce the new destination client region. 4mIntersect24m indicates that the source and destination regions are intersected together to produce the new destination client region. 4mSubtract24m indi- cates that the source region is subtracted from the destina- tion region to produce the new destination region. 4mInvert0m indicates that the destination region is subtracted from the source region to produce the new destination region. 1m4. Requests0m 1m40m X11 Nonrectangular Window Shape Extension Protocol __ | 4mShapeQueryVersion0m => majorVersion: CARD16 minorVersion: CARD16 |__ This request can be used to ensure that the server version of the SHAPE extension is usable by the client. This docu- ment defines major version one (1), minor version one (1). __ | 4mShapeRectangles0m 4mdest24m: WINDOW 4mdestKind24m: SHAPE_KIND 4mop24m: SHAPE_OP 4mxOff,24m 4myOff24m: INT16 4mrectangles24m: LISTofRECTANGLES 4mordering24m: {4mUnSorted24m, 4mYSorted24m, 4mYXSorted24m, 4mYXBanded24m} Errors: 4mWindow24m, 4mLength24m, 4mMatch24m, 4mValue0m |__ This request specifies an array of rectangles, relative to the origin of the window plus the specified offset (xOff and yOff) that together define a region. This region is com- bined (as specified by the operator op) with the existing client region (specified by destKind) of the destination window, and the result is stored as the specified client region of the destination window. Note that the list of rectangles can be empty, specifying an empty region; this is not the same as passing 4mNone24m to 4mShapeMask24m. If known by the client, ordering relations on the rectangles can be specified with the ordering argument. This may pro- vide faster operation by the server. The meanings of the ordering values are the same as in the core protocol 4mSet-0m 4mClipRectangles24m request. If an incorrect ordering is speci- fied, the server may generate a 4mMatch24m error, but it is not required to do so. If no error is generated, the graphics results are undefined. Except for 4mUnSorted24m, the rectangles should be nonintersecting, or the resulting region will be undefined. 4mUnSorted24m means that the rectangles are in arbi- trary order. 4mYSorted24m means that the rectangles are nonde- creasing in their Y origin. 4mYXSorted24m additionally con- strains 4mYSorted24m order in that all rectangles with an equal Y origin are nondecreasing in their X origin. 4mYXBanded24m addi- tionally constrains 4mYXSorted24m by requiring that, for every possible Y scanline, all rectangles that include that scan- line have identical Y origins and Y extents. 1m50m X11 Nonrectangular Window Shape Extension Protocol __ | 4mShapeMask0m 4mdest24m: WINDOW 4mdestKind24m: SHAPE_KIND 4mop24m: SHAPE_OP 4mxOff,24m 4myOff24m: INT16 4msource24m: PIXMAP or 4mNone0m Errors: 4mWindow24m, 4mPixmap24m, 4mMatch24m, 4mValue0m |__ The source in this request is a 1-bit deep pixmap, or 4mNone24m. If source is 4mNone24m, the specified client region is removed from the window, causing the effective region to revert to the default region. The 4mShapeNotify24m event generated by this request and subsequent 4mShapeQueryExtents24m will report that a client shape has not been specified. If a valid pixmap is specified, it is converted to a region, with bits set to one included in the region and bits set to zero excluded, and an offset from the window origin as specified by xOff and yOff. The resulting region is then combined (as specified by the operator op) with the existing client region (indicated by destKind) of the destination window, and the result is stored as the specified client region of the destination window. The source pixmap and destination window must have been created on the same screen, or else a 4mMatch24m error results. __ | 4mShapeCombine0m 4mdest24m: WINDOW 4mdestKind24m: SHAPE_KIND 4mop24m: SHAPE_OP 4mxOff,24m 4myOff24m: INT16 4msource24m: WINDOW 4msourceKind24m: SHAPE_KIND Errors: 4mWindow24m, 4mMatch24m, 4mValue0m |__ The client region, indicated by sourceKind, of the source window is offset from the window origin by xOff and yOff and combined with the client region, indicated by destKind, of the destination window. The result is stored as the speci- fied client region of the destination window. The source and destination windows must be on the same screen, or else a 4mMatch24m error results. 1m60m X11 Nonrectangular Window Shape Extension Protocol __ | 4mShapeOffset0m 4mdest24m: WINDOW 4mdestKind24m: SHAPE_KIND 4mxOff,24m 4myOff24m: INT16 Errors: 4mWindow24m, 4mMatch24m, 4mValue0m |__ The client region, indicated by destKind, is moved relative to its current position by the amounts xOff and yOff. __ | 4mShapeQueryExtents0m 4mdest24m: WINDOW => boundingShaped: BOOL clipShaped: BOOL xBoundingShape: INT16 yBoundingShape: INT16 widthBoundingShape: CARD16 heightBoundingShape: CARD16 xClipShape: INT16 yClipShape: INT16 widthClipShape: CARD16 heightClipShape: CARD16 Errors: 4mWindow0m |__ The boundingShaped and clipShaped results are 4mTrue24m if the corresponding client regions have been specified, else they are 4mFalse24m. The x, y, width, and height values define the extents of the client regions, when a client region has not been specified, the extents of the corresponding default region are reported. __ | 4mShapeSelectInput0m 4mwindow24m: WINDOW 4menable24m: BOOL Errors: 4mWindow24m, 4mValue0m |__ Specifying enable as 4mTrue24m causes the server to send the requesting client a 4mShapeNotify24m event whenever the bounding, clip or input region of the specified window is altered by any client. Specifying enable as 4mFalse24m causes the server to stop sending such events. 1m70m X11 Nonrectangular Window Shape Extension Protocol __ | 4mShapeInputSelected0m 4mwindow24m: WINDOW => enable: BOOL Errors: 4mWindow0m |__ If enable is 4mTrue24m, then 4mShapeNotify24m events for the window are generated for this client. __ | 4mShapeGetRectangles0m 4mwindow24m: WINDOW 4mkind24m: SHAPE_KIND => rectangles: LISTofRECTANGLE ordering: {4mUnSorted24m, 4mYSorted24m, 4mYXSorted24m, 4mYXBanded24m} Errors: 4mWindow,24m 4mMatch0m |__ A list of rectangles describing the region indicated by kind, and the ordering of those rectangles, is returned. The meaning of the ordering values is the same as in the 4mShapeRectangles24m request. 1m5. Events0m __ | 4mShapeNotify0m 4mwindow24m: WINDOW 4mkind24m: SHAPE_KIND 4mshaped24m: BOOL 4mx24m, 4my24m: INT16 4mwidth24m, 4mheight24m: CARD16 4mtime24m: TIMESTAMP |__ Whenever the client bounding, clip or input shape of a win- dow is modified, a 4mShapeNotify24m event is sent to each client that has used 4mShapeSelectInput24m to request it. Kind indicates which client region (bounding or clip) has been modified; shaped is 4mTrue24m when the window has a client shape of type kind, and is 4mFalse24m when the window no longer has a client shape of this type. The x, y, width, and 1m80m X11 Nonrectangular Window Shape Extension Protocol height indicate the extents of the current shape. When shaped is 4mFalse24m these will indicate the extents of the default region. The timestamp indicates the server time when the shape was changed. 1m6. Encoding0m Please refer to the X11 Protocol Encoding document as this document uses conventions established there. The name of this extension is ``SHAPE''. 1m6.1. New Types0m SHAPE_KIND 0 Bounding 1 Clip 2 Input SHAPE_OP 0 Set 1 Union 2 Intersect 3 Subtract 4 Invert 1m6.2. Requests0m 4mShapeQueryVersion0m 1 CARD8 opcode 1 0 shape opcode 2 1 request length => 1 1 Reply 1 unused 2 CARD16 sequence number 4 0 length 2 CARD16 major version 2 CARD16 minor version 20 unused 4mShapeRectangles0m 1 CARD8 opcode 1 1 shape opcode 1m90m X11 Nonrectangular Window Shape Extension Protocol 2 4+2n request length 1 SHAPE_OP operation 1 SHAPE_KIND destination kind 1 ordering 0 UnSorted 1 YSorted 2 YXSorted 3 YXBanded 1 unused 4 WINDOW destination window 2 INT16 x offset 2 INT16 y offset 8n LISTofRECTANGLE rectangles 4mShapeMask0m 1 CARD8 opcode 1 2 shape opcode 2 5 request length 1 SHAPE_OP operation 1 SHAPE_KIND destination kind 2 unused 4 WINDOW destination window 2 INT16 x offset 2 INT16 y offset 4 PIXMAP source bitmap 0 None 4mShapeCombine0m 1 CARD8 opcode 1 3 shape opcode 2 5 request length 1 SHAPE_OP operation 1 SHAPE_KIND destination kind 1 SHAPE_KIND source kind 1 unused 4 WINDOW destination window 2 INT16 x offset 2 INT16 y offset 4 WINDOW source window 4mShapeOffset0m 1 CARD8 opcode 1 4 shape opcode 2 4 request length 1 SHAPE_KIND destination kind 3 unused 4 WINDOW destination window 2 INT16 x offset 1m100m X11 Nonrectangular Window Shape Extension Protocol 2 INT16 y offset 4mShapeQueryExtents0m 1 CARD8 opcode 1 5 shape opcode 2 2 request length 4 WINDOW destination window => 1 1 Reply 1 unused 2 CARD16 sequence number 4 0 reply length 1 BOOL bounding shaped 1 BOOL clip shaped 2 unused 2 INT16 bounding shape extents x 2 INT16 bounding shape extents y 2 CARD16 bounding shape extents width 2 CARD16 bounding shape extents height 2 INT16 clip shape extents x 2 INT16 clip shape extents y 2 CARD16 clip shape extents width 2 CARD16 clip shape extents height 4 unused 4mShapeSelectInput0m 1 CARD8 opcode 1 6 shape opcode 2 3 request length 4 WINDOW destination window 1 BOOL enable 3 unused 4mShapeInputSelected0m 1 CARD8 opcode 1 6 shape opcode 2 2 request length 4 WINDOW destination window => 1 1 Reply 1 BOOL enabled 2 CARD16 sequence number 4 0 reply length 24 unused 1m110m X11 Nonrectangular Window Shape Extension Protocol 4mShapeGetRectangles0m 1 CARD8 opcode 1 7 shape opcode 2 3 request length 4 WINDOW window 1 SHAPE_KIND source kind 3 unused => 1 1 Reply 1 ordering 0 UnSorted 1 YSorted 2 YXSorted 3 YXBanded 2 CARD16 sequence number 4 2n reply length 4 CARD32 nrects 20 unused 8n LISTofRECTANGLE rectangles 1m6.3. Events0m 4mShapeNotify0m 1 CARD8 type (0 + extension event base) 1 SHAPE_KIND shape kind 2 CARD16 sequence number 4 WINDOW affected window 2 INT16 x value of extents 2 INT16 y value of extents 2 CARD16 width of extents 2 CARD16 height of extents 4 TIMESTAMP server time 1 BOOL shaped 11 unused 1m7. Glossary0m 1mbounding region0m The area of the parent window that this window will occupy. This area is divided into two parts: the bor- der and the interior. 1m120m X11 Nonrectangular Window Shape Extension Protocol 1mclip region0m The interior of the window, as a subset of the bounding region. This region describes the area that will be painted with the window background when the window is cleared, will contain all graphics output to the win- dow, and will clip any subwindows. 1minput region0m The subset of the bounding region which can ``contain'' the pointer. 1mdefault bounding region0m The rectangular area, as described by the core protocol window size, that covers the interior of the window and its border. 1mdefault clip region0m The rectangular area, as described by the core protocol window size, that covers the interior of the window and excludes the border. 1mdefault input region0m The rectangular area, as described by the core protocol window size, that covers the interior of the window and its border. 1mclient bounding region0m The region associated with a window that is directly modified via this extension when specified by 4mShape-0m 4mBounding24m. This region is used in conjunction with the default bounding region to produce the effective bound- ing region. 1mclient clip region0m The region associated with a window that is directly modified via this extension when specified by 4mShapeClip24m. This region is used in conjunction with the default clip region and the client bounding region to produce the effective clip region. 1m130m X11 Nonrectangular Window Shape Extension Protocol 1mclient input region0m The region associated with a window that is directly modified via this extension when specified by 4mShapeIn-0m 4mput24m. This region is used in conjunction with the default input region and the client bounding region to produce the effective input region. 1meffective bounding region0m The actual shape of the window on the screen, including border and interior (but excluding the effects of over- lapping windows). When a window has a client bounding region, the effective bounding region is the intersec- tion of the default bounding region and the client bounding region. Otherwise, the effective bounding region is the same as the default bounding region. 1meffective clip region0m The actual shape of the interior of the window on the screen (excluding the effects of overlapping windows). When a window has a client clip region or a client bounding region, the effective clip region is the intersection of the default clip region, the client clip region (if any) and the client bounding region (if any). Otherwise, the effective clip region is the same as the default clip region. 1meffective input region0m The actual shape of the window on the screen (excluding the effects of overlapping windows) which can ``con- tain'' the pointer. When a window has a client input region or a client bounding region, the effective input region is the intersection of the default input region, the client input region (if any) and the client bound- ing region (if any). Otherwise, the effective input region is the same as the default input region. 1m140m