The hotspot comes from the information stored in the cursor font. The initial colors of a cursor are a black foreground and a white background (see _X_R_e_c_o_l_o_r_C_u_r_s_o_r).
_X_C_r_e_a_t_e_F_o_n_t_C_u_r_s_o_r can generate _B_a_d_A_l_l_o_c and _B_a_d_V_a_l_u_e errors.
The _X_C_r_e_a_t_e_P_i_x_m_a_p_C_u_r_s_o_r function creates a cursor and returns the cursor ID associated with it. The foreground and background RGB values must be specified using foreground_color and background_color, even if the X server only has a _S_t_a_t_i_c_G_r_a_y or _G_r_a_y_S_c_a_l_e screen. The foreground color is used for the pixels set to 1 in the source, and the background color is used for the pixels set to 0. Both source and mask, if specified, must have depth one (or a _B_a_d_M_a_t_c_h error results) but can have any root. The mask argument defines the shape of the cursor. The pixels set to 1 in the mask define which source pixels are displayed, and the pixels set to 0 define which pixels are ignored. If no mask is given, all pixels of the source are displayed. The mask, if present, must be the same size as the pixmap defined by the source argument, or a _B_a_d_M_a_t_c_h error results. The hotspot must be a point within the source, or a _B_a_d_M_a_t_c_h error results.
The components of the cursor can be transformed arbitrarily to meet display limitations. The pixmaps can be freed immediately if no further explicit references to them are to be made. Subsequent drawing in the source or mask pixmap has an undefined effect on the cursor. The X server might or might not make a copy of the pixmap.
_X_C_r_e_a_t_e_P_i_x_m_a_p_C_u_r_s_o_r can generate _B_a_d_A_l_l_o_c and _B_a_d_P_i_x_m_a_p errors.
The _X_C_r_e_a_t_e_G_l_y_p_h_C_u_r_s_o_r function is similar to _X_C_r_e_a_t_e_P_i_x_m_a_p_C_u_r_s_o_r except that the source and mask bitmaps are obtained from the specified font glyphs. The source_char must be a defined glyph in source_font, or a _B_a_d_V_a_l_u_e error results. If mask_font is given, mask_char must be a defined glyph in mask_font, or a _B_a_d_V_a_l_u_e error results. The mask_font and character are optional. The origins of the source_char and mask_char (if defined) glyphs are positioned coincidently and define the hotspot. The source_char and mask_char need not have the same bounding box metrics, and there is no restriction on the placement of the hotspot relative to the bounding boxes. If no mask_char is given, all pixels of the source are displayed. You can free the fonts immediately by calling _X_F_r_e_e_F_o_n_t if no further explicit references to them are to be made.
For 2-byte matrix fonts, the 16-bit value should be formed with the byte1 member in the most significant byte and the byte2 member in the least significant byte.
_X_C_r_e_a_t_e_G_l_y_p_h_C_u_r_s_o_r can generate _B_a_d_A_l_l_o_c, _B_a_d_F_o_n_t, and _B_a_d_V_a_l_u_e errors.