XCreateGC(3X11) AIX (XLIB FUNCTIONS) XCreateGC(3X11) NAME XCreateGC, XCopyGC, XChangeGC, XGetGCValues, XFreeGC, XGCon- textFromGC, XGCValues - create or free graphics contexts and graphics context structure SYNTAX GC XCreateGC(_d_i_s_p_l_a_y, _d, _v_a_l_u_e_m_a_s_k, _v_a_l_u_e_s) Display *_d_i_s_p_l_a_y; Drawable _d; unsigned long _v_a_l_u_e_m_a_s_k; XGCValues *_v_a_l_u_e_s; XCopyGC(_d_i_s_p_l_a_y, _s_r_c, _v_a_l_u_e_m_a_s_k, _d_e_s_t) Display *_d_i_s_p_l_a_y; GC _s_r_c, _d_e_s_t; unsigned long _v_a_l_u_e_m_a_s_k; XChangeGC(_d_i_s_p_l_a_y, _g_c, _v_a_l_u_e_m_a_s_k, _v_a_l_u_e_s) Display *_d_i_s_p_l_a_y; GC _g_c; unsigned long _v_a_l_u_e_m_a_s_k; XGCValues *_v_a_l_u_e_s; Status XGetGCValues(_d_i_s_p_l_a_y, _g_c, _v_a_l_u_e_m_a_s_k, _v_a_l_u_e_s__r_e_t_u_r_n) Display *_d_i_s_p_l_a_y; GC _g_c; unsigned long _v_a_l_u_e_m_a_s_k; XGCValues *_v_a_l_u_e_s__r_e_t_u_r_n; XFreeGC(_d_i_s_p_l_a_y, _g_c) Display *_d_i_s_p_l_a_y; GC _g_c; GContext XGContextFromGC(_g_c) GC _g_c; ARGUMENTS _d Specifies the drawable. _d_e_s_t Specifies the destination GC. _d_i_s_p_l_a_y Specifies the connection to the X server. _g_c Specifies the GC. _s_r_c Specifies the components of the source GC. _v_a_l_u_e_m_a_s_k Specifies which components in the GC are to be set, copied, changed, or returned . This argument is the bitwise inclusive OR of zero or more of the valid GC component mask bits. _v_a_l_u_e_s Specifies any values as specified by the Rev. Release 5 Page 1 XCreateGC(3X11) AIX (XLIB FUNCTIONS) XCreateGC(3X11) valuemask. _v_a_l_u_e_s__r_e_t_u_r_n Returns the GC values in the specified _X_G_C_V_a_l_u_e_s structure. DESCRIPTION The _X_C_r_e_a_t_e_G_C function creates a graphics context and returns a GC. The GC can be used with any destination draw- able having the same root and depth as the specified draw- able. Use with other drawables results in a _B_a_d_M_a_t_c_h error. _X_C_r_e_a_t_e_G_C can generate _B_a_d_A_l_l_o_c, _B_a_d_D_r_a_w_a_b_l_e, _B_a_d_F_o_n_t, _B_a_d_- _M_a_t_c_h, _B_a_d_P_i_x_m_a_p, and _B_a_d_V_a_l_u_e errors. The _X_C_o_p_y_G_C function copies the specified components from the source GC to the destination GC. The source and desti- nation GCs must have the same root and depth, or a _B_a_d_M_a_t_c_h error results. The valuemask specifies which component to copy, as for _X_C_r_e_a_t_e_G_C. _X_C_o_p_y_G_C can generate _B_a_d_A_l_l_o_c, _B_a_d_G_C, and _B_a_d_M_a_t_c_h errors. The _X_C_h_a_n_g_e_G_C function changes the components specified by valuemask for the specified GC. The values argument con- tains the values to be set. The values and restrictions are the same as for _X_C_r_e_a_t_e_G_C. Changing the clip-mask overrides any previous _X_S_e_t_C_l_i_p_R_e_c_t_a_n_g_l_e_s request on the context. Changing the dash-offset or dash-list overrides any previous _X_S_e_t_D_a_s_h_e_s request on the context. The order in which com- ponents are verified and altered is server-dependent. If an error is generated, a subset of the components may have been altered. _X_C_h_a_n_g_e_G_C can generate _B_a_d_A_l_l_o_c, _B_a_d_F_o_n_t, _B_a_d_G_C, _B_a_d_M_a_t_c_h, _B_a_d_P_i_x_m_a_p, and _B_a_d_V_a_l_u_e errors. The _X_G_e_t_G_C_V_a_l_u_e_s function returns the components specified by valuemask for the specified GC. If the valuemask con- tains a valid set of GC mask bits (_G_C_F_u_n_c_t_i_o_n, _G_C_P_l_a_n_e_M_a_s_k, _G_C_F_o_r_e_g_r_o_u_n_d, _G_C_B_a_c_k_g_r_o_u_n_d, _G_C_L_i_n_e_W_i_d_t_h, _G_C_L_i_n_e_S_t_y_l_e, _G_C_C_a_p_S_t_y_l_e, _G_C_J_o_i_n_S_t_y_l_e, _G_C_F_i_l_l_S_t_y_l_e, _G_C_F_i_l_l_R_u_l_e, _G_C_T_i_l_e, _G_C_S_t_i_p_p_l_e, _G_C_T_i_l_e_S_t_i_p_X_O_r_i_g_i_n, _G_C_T_i_l_e_S_t_i_p_Y_O_r_i_g_i_n, _G_C_F_o_n_t, _G_C_S_u_b_w_i_n_d_o_w_M_o_d_e, _G_C_G_r_a_p_h_i_c_s_E_x_p_o_s_u_r_e_s, _G_C_C_l_i_p_X_O_r_i_g_i_n, _G_C_C_L_i_- _p_Y_O_r_i_g_i_n, _G_C_D_a_s_h_O_f_f_s_e_t, or _G_C_A_r_c_M_o_d_e) and no error occur, _X_G_e_t_G_C_V_a_l_u_e_s sets the requested components in values_return and returns a nonzero status. Otherwise, it returns a zero status. Note that the clip-mask and dash-list (represented by the _G_C_C_l_i_p_M_a_s_k and _G_C_D_a_s_h_L_i_s_t bits, respectively, in the valuemask) cannot be requested. Also note that an invalid resource ID (with one or more of the three most-significant bits set to one) will be returned for _G_C_F_o_n_t, _G_C_T_i_l_e, and _G_C_S_t_i_p_p_l_e if the component has never been explicitly set by Rev. Release 5 Page 2 XCreateGC(3X11) AIX (XLIB FUNCTIONS) XCreateGC(3X11) the client. The _X_F_r_e_e_G_C function destroys the specified GC as well as all the associated storage. _X_F_r_e_e_G_C can generate a _B_a_d_G_C error. STRUCTURES The _X_G_C_V_a_l_u_e_s structure contains: /* GC attribute value mask bits */ lw(.5i) lw(2.5i) lw(.75i). #define T{ _G_C_F_u_n_c_t_i_o_n T} T{ (1L<<0) T} #define T{ _G_C_P_l_a_n_e_M_a_s_k T} T{ (1L<<1) T} #define T{ _G_C_F_o_r_e_g_r_o_u_n_d T} T{ (1L<<2) T} #define T{ _G_C_B_a_c_k_g_r_o_u_n_d T} T{ (1L<<3) T} #define T{ _G_C_L_i_n_e_W_i_d_t_h T} T{ (1L<<4) T} #define T{ _G_C_L_i_n_e_S_t_y_l_e T} T{ (1L<<5) T} #define T{ _G_C_C_a_p_S_t_y_l_e T} T{ (1L<<6) T} #define T{ _G_C_J_o_i_n_S_t_y_l_e T} T{ (1L<<7) T} #define T{ _G_C_F_i_l_l_S_t_y_l_e T} T{ (1L<<8) T} #define T{ _G_C_F_i_l_l_R_u_l_e T} T{ (1L<<9) T} #define T{ _G_C_T_i_l_e T} T{ (1L<<10) T} #define T{ _G_C_S_t_i_p_p_l_e T} T{ (1L<<11) T} #define T{ _G_C_T_i_l_e_S_t_i_p_X_O_r_i_g_i_n T} T{ (1L<<12) T} #define T{ _G_C_T_i_l_e_S_t_i_p_Y_O_r_i_g_i_n T} T{ (1L<<13) T} #define T{ _G_C_F_o_n_t T} T{ (1L<<14) T} #define T{ _G_C_S_u_b_w_i_n_d_o_w_M_o_d_e T} T{ (1L<<15) T} #define T{ _G_C_G_r_a_- _p_h_i_c_s_E_x_p_o_s_u_r_e_s T} T{ (1L<<16) T} #define T{ _G_C_C_l_i_p_X_O_r_i_- _g_i_n T} T{ (1L<<17) T} #define T{ _G_C_C_l_i_p_Y_O_r_i_g_i_n T} T{ (1L<<18) T} #define T{ _G_C_C_l_i_p_M_a_s_k T} T{ (1L<<19) T} #define T{ _G_C_D_a_s_h_O_f_f_s_e_t T} T{ (1L<<20) T} #define T{ _G_C_D_a_s_h_L_i_s_t T} T{ (1L<<21) T} #define T{ _G_C_A_r_c_M_o_d_e T} T{ (1L<<22) T} /* Values */ typedef struct { int function; /* logical operation */ unsigned long plane_mask;/* plane mask */ unsigned long foreground;/* foreground pixel */ unsigned long background;/* background pixel */ int line_width; /* line width (in pixels) */ int line_style; /* LineSolid, LineOnOffDash, LineDoubleDash */ int cap_style; /* CapNotLast, CapButt, CapRound, CapProjecting */ int join_style; /* JoinMiter, JoinRound, JoinBevel */ int fill_style; /* FillSolid, FillTiled, FillStippled FillOpaqueStippled*/ int fill_rule; /* EvenOddRule, WindingRule */ int arc_mode; /* ArcChord, ArcPieSlice */ Pixmap tile; /* tile pixmap for tiling operations */ Pixmap stipple; /* stipple 1 plane pixmap for stippling */ int ts_x_origin; /* offset for tile or stipple operations */ int ts_y_origin; Font font; /* default text font for text operations */ int subwindow_mode; /* ClipByChildren, IncludeInferiors */ Bool graphics_exposures; /* boolean, should exposures be generated */ int clip_x_origin; /* origin for clipping */ int clip_y_origin; Rev. Release 5 Page 3 XCreateGC(3X11) AIX (XLIB FUNCTIONS) XCreateGC(3X11) Pixmap clip_mask; /* bitmap clipping; other calls for rects */ int dash_offset; /* patterned/dashed line information */ char dashes; } XGCValues; The function attributes of a GC are used when you update a section of a drawable (the destination) with bits from some- where else (the source). The function in a GC defines how the new destination bits are to be computed from the source bits and the old destination bits. _G_X_c_o_p_y is typically the most useful because it will work on a color display, but special applications may use other functions, particularly in concert with particular planes of a color display. The 16 GC functions, defined in <_X_1_1/_X._h>, are: lw(1.5i) cw(.5i) lw(2i). _ 9 FFFFuuuunnnnccccttttiiiioooonnnn NNNNaaaammmmeeee VVVVaaaalllluuuueeeeOOOOppppeeeerrrraaaattttiiiioooonnnn 9 _ 9 T{ _G_X_c_l_e_a_r T} T{ 0x0 T} T{ 0 T} T{ _G_X_a_n_d T} T{ 0x1 T} T{ src AND dst T} T{ _G_X_a_n_d_R_e_v_e_r_s_e T} T{ 0x2 T} T{ src AND NOT dst T} T{ _G_X_c_o_p_y T} T{ 0x3 T} T{ src T} T{ _G_X_a_n_d_I_n_v_e_r_t_e_d T} T{ 0x4 T} T{ (NOT src) AND dst T} T{ _G_X_n_o_o_p T} T{ 0x5 T} T{ dst T} T{ _G_X_x_o_r T} T{ 0x6 T} T{ src XOR dst T} T{ _G_X_o_r T} T{ 0x7 T} T{ src OR dst T} T{ _G_X_n_o_r T} T{ 0x8 T} T{ (NOT src) AND (NOT dst) T} T{ _G_X_e_q_u_i_v T} T{ 0x9 T} T{ (NOT src) XOR dst T} T{ _G_X_i_n_v_e_r_t T} T{ 0xa T} T{ NOT dst T} T{ _G_X_o_r_R_e_v_e_r_s_e T} T{ 0xb T} T{ src OR (NOT dst) T} T{ _G_X_c_o_p_y_I_n_v_e_r_t_e_d T} T{ 0xc T} T{ NOT src T} T{ _G_X_o_r_I_n_v_e_r_t_e_d T} T{ 0xd T} T{ (NOT src) OR dst T} T{ _G_X_n_a_n_d T} T{ 0xe T} T{ (NOT src) OR (NOT dst) T} T{ _G_X_s_e_t T} T{ 0xf T} T{ 1 T} 9 _ Many graphics operations depend on either pixel values or planes in a GC. The planes attribute is of type long, and it specifies which planes of the destination are to be modi- fied, one bit per plane. A monochrome display has only one plane and will be the least-significant bit of the word. As planes are added to the display hardware, they will occupy more significant bits in the plane mask. In graphics operations, given a source and destination pixel, the result is computed bitwise on corresponding bits of the pixels. That is, a Boolean operation is performed in each bit plane. The plane_mask restricts the operation to a subset of planes. A macro constant _A_l_l_P_l_a_n_e_s can be used to refer to all planes of the screen simultaneously. The result is computed by the following: ((src FUNC dst) AND plane-mask) OR (dst AND (NOT plane-mask)) Range checking is not performed on the values for Rev. Release 5 Page 4 XCreateGC(3X11) AIX (XLIB FUNCTIONS) XCreateGC(3X11) foreground, background, or plane_mask. They are simply truncated to the appropriate number of bits. The line-width is measured in pixels and either can be greater than or equal to one (wide line) or can be the special value zero (thin line). Wide lines are drawn centered on the path described by the graphics request. Unless otherwise specified by the join- style or cap-style, the bounding box of a wide line with endpoints [x1, y1], [x2, y2] and width w is a rectangle with vertices at the following real coordinates: [x1-(w*sn/2), y1+(w*cs/2)], [x1+(w*sn/2), y1-(w*cs/2)], [x2-(w*sn/2), y2+(w*cs/2)], [x2+(w*sn/2), y2-(w*cs/2)] Here sn is the sine of the angle of the line, and cs is the cosine of the angle of the line. A pixel is part of the line and so is drawn if the center of the pixel is fully inside the bounding box (which is viewed as having infin- itely thin edges). If the center of the pixel is exactly on the bounding box, it is part of the line if and only if the interior is immediately to its right (x increasing direc- tion). Pixels with centers on a horizontal edge are a spe- cial case and are part of the line if and only if the inte- rior or the boundary is immediately below (y increasing direction) and the interior or the boundary is immediately to the right (x increasing direction). Thin lines (zero line-width) are one-pixel-wide lines drawn using an unspecified, device-dependent algorithm. There are only two constraints on this algorithm. 1. If a line is drawn unclipped from [x1,y1] to [x2,y2] and if another line is drawn unclipped from [x1+dx,y1+dy] to [x2+dx,y2+dy], a point [x,y] is touched by drawing the first line if and only if the point [x+dx,y+dy] is touched by drawing the second line. 2. The effective set of points comprising a line cannot be affected by clipping. That is, a point is touched in a clipped line if and only if the point lies inside the clipping region and the point would be touched by the line when drawn unclipped. A wide line drawn from [x1,y1] to [x2,y2] always draws the same pixels as a wide line drawn from [x2,y2] to [x1,y1], not counting cap-style and join-style. It is recommended that this property be true for thin lines, but this is not required. A line-width of zero may differ from a line-width of one in which pixels are drawn. This permits the use of many manufacturers' line drawing hardware, which may run many times faster than the more precisely specified wide Rev. Release 5 Page 5 XCreateGC(3X11) AIX (XLIB FUNCTIONS) XCreateGC(3X11) lines. In general, drawing a thin line will be faster than drawing a wide line of width one. However, because of their dif- ferent drawing algorithms, thin lines may not mix well aesthetically with wide lines. If it is desirable to obtain precise and uniform results across all displays, a client should always use a line-width of one rather than a line- width of zero. The line-style defines which sections of a line are drawn: lw(1.3i) lw(4.5i). T{ _L_i_n_e_S_o_l_i_d T} T{ The full path of the line is drawn. T} 9 T{ _L_i_n_e_D_o_u_b_l_e_D_a_s_h T} T{ The full path of the line is drawn, but the even dashes are filled differently than the odd dashes (see fill-style) with _C_a_p_B_u_t_t style used where even and odd dashes meet. T} 9 T{ _L_i_n_e_O_n_O_f_f_D_a_s_h T} T{ Only the even dashes are drawn, and cap-style applies to all internal ends of the individual dashes, except _C_a_p_N_o_t_L_a_s_t is treated as _C_a_p_B_u_t_t. T} The cap-style defines how the endpoints of a path are drawn: lw(1.3i) lw(4.5i). T{ _C_a_p_N_o_t_L_a_s_t T} T{ This is equivalent to _C_a_p_B_u_t_t except that for a line-width of zero the final endpoint is not drawn. T} 9 T{ _C_a_p_B_u_t_t T} T{ The line is square at the endpoint (per- pendicular to the slope of the line) with no projection beyond. T} 9 T{ _C_a_p_R_o_u_n_d T} T{ The line has a circular arc with the diameter equal to the line-width, centered on the endpoint. (This is equivalent to _C_a_p_B_u_t_t for line-width of zero). T} 9 T{ _C_a_p_P_r_o_j_e_c_t_i_n_g T} T{ The line is square at the end, but the path continues beyond the endpoint for a distance equal to half the line-width. (This is equivalent to _C_a_p_B_u_t_t for line-width of zero). T} The join-style defines how corners are drawn for wide lines: lw(1.3i) lw(4.5i). T{ _J_o_i_n_M_i_t_e_r T} T{ The outer edges of two lines extend to meet at an angle. However, if the angle is less than 11 degrees, then a _J_o_i_n_B_e_v_e_l join-style is used instead. T} 9 T{ _J_o_i_n_R_o_u_n_d T} T{ The corner is a circular arc with the diameter equal to the line-width, centered on the joinpoint. T} 9 T{ _J_o_i_n_B_e_v_e_l T} T{ The corner has _C_a_p_B_u_t_t endpoint styles with the triangular notch filled. T} For a line with coincident endpoints (x1=x2, y1=y2), when the cap-style is applied to both endpoints, the semantics depends on the line-width and the cap-style: lw(1.3i) 9 Rev. Release 5 Page 6 XCreateGC(3X11) AIX (XLIB FUNCTIONS) XCreateGC(3X11) lw(.5i) lw(4i). T{ _C_a_p_N_o_t_L_a_s_t T} T{ thin T} T{ The results are device-dependent, but the desired effect is that nothing is drawn. T} 9 T{ _C_a_p_B_u_t_t T} T{ thin T} T{ The results are device- dependent, but the desired effect is that a single pixel is drawn. T} 9 T{ _C_a_p_R_o_u_n_d T} T{ thin T} T{ The results are the same as for _C_a_p_B_u_t_t/thin. T} 9 T{ _C_a_p_P_r_o_j_e_c_t_i_n_g T} T{ thin T} T{ The results are the same as for _B_u_t_t/thin. T} 9 T{ _C_a_p_B_u_t_t T} T{ wide T} T{ Nothing is drawn. T} 9 T{ _C_a_p_R_o_u_n_d T} T{ wide T} T{ The closed path is a cir- cle, centered at the endpoint, and with the diameter equal to the line-width. T} 9 T{ _C_a_p_P_r_o_j_e_c_t_i_n_g T} T{ wide T} T{ The closed path is a square, aligned with the coordinate axes, centered at the endpoint, and with the sides equal to the line-width. T} For a line with coincident endpoints (x1=x2, y1=y2), when the join-style is applied at one or both endpoints, the effect is as if the line was removed from the overall path. However, if the total path consists of or is reduced to a single point joined with itself, the effect is the same as when the cap-style is applied at both endpoints. The tile/stipple represents an infinite 2D plane, with the tile/stipple replicated in all dimensions. When that plane is superimposed on the drawable for use in a graphics opera- tion, the upper left corner of some instance of the tile/stipple is at the coordinates within the drawable specified by the tile/stipple origin. The tile/stipple and clip origins are interpreted relative to the origin of what- ever destination drawable is specified in a graphics request. The tile pixmap must have the same root and depth as the GC, or a _B_a_d_M_a_t_c_h error results. The stipple pixmap must have depth one and must have the same root as the GC, or a _B_a_d_M_a_t_c_h error results. For stipple operations where the fill-style is _F_i_l_l_S_t_i_p_p_l_e_d but not _F_i_l_l_O_p_a_q_u_e_S_t_i_p_p_l_e_d, the stipple pattern is tiled in a single plane and acts as an additional clip mask to be ANDed with the clip-mask. Although some sizes may be faster to use than others, any size pixmap can be used for tiling or stippling. The fill-style defines the contents of the source for line, text, and fill requests. For all text and fill requests (for example, _X_D_r_a_w_T_e_x_t, _X_D_r_a_w_T_e_x_t_1_6, _X_F_i_l_l_R_e_c_t_a_n_g_l_e, _X_F_i_l_l_P_o_- _l_y_g_o_n, and _X_F_i_l_l_A_r_c); for line requests with line-style _L_i_n_e_S_o_l_i_d (for example, _X_D_r_a_w_L_i_n_e, _X_D_r_a_w_S_e_g_m_e_n_t_s, _X_D_r_a_w_R_e_c_- _t_a_n_g_l_e, _X_D_r_a_w_A_r_c); and for the even dashes for line requests with line-style _L_i_n_e_O_n_O_f_f_D_a_s_h or _L_i_n_e_D_o_u_b_l_e_D_a_s_h, the Rev. Release 5 Page 7 XCreateGC(3X11) AIX (XLIB FUNCTIONS) XCreateGC(3X11) following apply: lw(1.8i) lw(4i). T{ _F_i_l_l_S_o_l_i_d T} T{ Foreground T} 9 T{ _F_i_l_l_T_i_l_e_d T} T{ Tile T} 9 T{ _F_i_l_l_O_p_a_q_u_e_S_t_i_p_p_l_e_d T} T{ A tile with the same width and height as stipple, but with background everywhere stipple has a zero and with foreground everywhere stipple has a one T} 9 T{ _F_i_l_l_S_t_i_p_p_l_e_d T} T{ Foreground masked by stipple T} When drawing lines with line-style _L_i_n_e_D_o_u_b_l_e_D_a_s_h, the odd dashes are controlled by the fill-style in the following manner: lw(1.8i) lw(4i). T{ _F_i_l_l_S_o_l_i_d T} T{ Background T} 9 T{ _F_i_l_l_T_i_l_e_d T} T{ Same as for even dashes T} 9 T{ _F_i_l_l_O_p_a_q_u_e_S_t_i_p_p_l_e_d T} T{ Same as for even dashes T} 9 T{ _F_i_l_l_S_t_i_p_p_l_e_d T} T{ Background masked by stipple T} Storing a pixmap in a GC might or might not result in a copy being made. If the pixmap is later used as the destination for a graphics request, the change might or might not be reflected in the GC. If the pixmap is used simultaneously in a graphics request both as a destination and as a tile or stipple, the results are undefined. For optimum performance, you should draw as much as possible with the same GC (without changing its components). The costs of changing GC components relative to using different GCs depend upon the display hardware and the server imple- mentation. It is quite likely that some amount of GC infor- mation will be cached in display hardware and that such hardware can only cache a small number of GCs. The dashes value is actually a simplified form of the more general patterns that can be set with _X_S_e_t_D_a_s_h_e_s. Specify- ing a value of N is equivalent to specifying the two-element list [N, N] in _X_S_e_t_D_a_s_h_e_s. The value must be nonzero, or a _B_a_d_V_a_l_u_e error results. The clip-mask restricts writes to the destination drawable. If the clip-mask is set to a pixmap, it must have depth one and have the same root as the GC, or a _B_a_d_M_a_t_c_h error results. If clip-mask is set to _N_o_n_e, the pixels are always drawn regardless of the clip origin. The clip-mask also can be set by calling the _X_S_e_t_C_l_i_p_R_e_c_t_a_n_g_l_e_s or _X_S_e_t_R_e_g_i_o_n func- tions. Only pixels where the clip-mask has a bit set to 1 are drawn. Pixels are not drawn outside the area covered by the clip-mask or where the clip-mask has a bit set to 0. The clip-mask affects all graphics requests. The clip-mask does not clip sources. The clip-mask origin is interpreted relative to the origin of whatever destination drawable is specified in a graphics request. Rev. Release 5 Page 8 XCreateGC(3X11) AIX (XLIB FUNCTIONS) XCreateGC(3X11) You can set the subwindow-mode to _C_l_i_p_B_y_C_h_i_l_d_r_e_n or _I_n_c_l_u_- _d_e_I_n_f_e_r_i_o_r_s. For _C_l_i_p_B_y_C_h_i_l_d_r_e_n, both source and destina- tion windows are additionally clipped by all viewable _I_n_p_u_- _t_O_u_t_p_u_t children. For _I_n_c_l_u_d_e_I_n_f_e_r_i_o_r_s, neither source nor destination window is clipped by inferiors. This will result in including subwindow contents in the source and drawing through subwindow boundaries of the destination. The use of _I_n_c_l_u_d_e_I_n_f_e_r_i_o_r_s on a window of one depth with mapped infe- riors of differing depth is not illegal, but the semantics are undefined by the core protocol. The fill-rule defines what pixels are inside (drawn) for paths given in _X_F_i_l_l_P_o_l_y_g_o_n requests and can be set to _E_v_e_n_O_d_d_R_u_l_e or _W_i_n_d_i_n_g_R_u_l_e. For _E_v_e_n_O_d_d_R_u_l_e, a point is inside if an infinite ray with the point as origin crosses the path an odd number of times. For _W_i_n_d_i_n_g_R_u_l_e, a point is inside if an infinite ray with the point as origin crosses an unequal number of clockwise and counterclockwise directed path segments. A clockwise directed path segment is one that crosses the ray from left to right as observed from the point. A counterclockwise segment is one that crosses the ray from right to left as observed from the point. The case where a directed line segment is coincident with the ray is uninteresting because you can simply choose a different ray that is not coincident with a segment. For both _E_v_e_n_O_d_d_R_u_l_e and _W_i_n_d_i_n_g_R_u_l_e, a point is infinitely small, and the path is an infinitely thin line. A pixel is inside if the center point of the pixel is inside and the center point is not on the boundary. If the center point is on the boundary, the pixel is inside if and only if the polygon interior is immediately to its right (x increasing direction). Pixels with centers on a horizontal edge are a special case and are inside if and only if the polygon inte- rior is immediately below (y increasing direction). The arc-mode controls filling in the _X_F_i_l_l_A_r_c_s function and can be set to _A_r_c_P_i_e_S_l_i_c_e or _A_r_c_C_h_o_r_d. For _A_r_c_P_i_e_S_l_i_c_e, the arcs are pie-slice filled. For _A_r_c_C_h_o_r_d, the arcs are chord filled. The graphics-exposure flag controls _G_r_a_p_h_i_c_s_E_x_p_o_s_e event generation for _X_C_o_p_y_A_r_e_a and _X_C_o_p_y_P_l_a_n_e requests (and any similar requests defined by extensions). DIAGNOSTICS _B_a_d_A_l_l_o_c The server failed to allocate the requested resource or server memory. _B_a_d_D_r_a_w_a_b_l_e A value for a Drawable argument does not name a defined Window or Pixmap. Rev. Release 5 Page 9 XCreateGC(3X11) AIX (XLIB FUNCTIONS) XCreateGC(3X11) _B_a_d_F_o_n_t A value for a Font or GContext argument does not name a defined Font. _B_a_d_G_C A value for a GContext argument does not name a defined GContext. _B_a_d_M_a_t_c_h An _I_n_p_u_t_O_n_l_y window is used as a Drawable. _B_a_d_M_a_t_c_h Some argument or pair of arguments has the correct type and range but fails to match in some other way required by the request. _B_a_d_P_i_x_m_a_p A value for a Pixmap argument does not name a defined Pixmap. _B_a_d_V_a_l_u_e Some numeric value falls outside the range of values accepted by the request. Unless a specific range is specified for an argument, the full range defined by the argument's type is accepted. Any argument defined as a set of alternatives can gen- erate this error. SEE ALSO AllPlanes(3X11), XCopyArea(3X11), XCreateRegion(3X11), XDrawArc(3X11), XDrawLine(3X11), XDrawRectangle(3X11), XDrawText(3X11), XFillRectangle(3X11), XQueryBestSize(3X11), XSetArcMode(3X11), XSetClipOrigin(3X11), XSetFillStyle(3X11), XSetFont(3X11), XSetLineAttributes(3X11), XSetState(3X11), XSetTile(3X11) _X_l_i_b - _C _L_a_n_g_u_a_g_e _X _I_n_t_e_r_f_a_c_e Rev. Release 5 Page 10