/src/wrappers/gdk/library/gdk_gc.e
Specman e | 87 lines | 43 code | 16 blank | 28 comment | 2 complexity | 620082b81d2f4a7b2778b5bd6b02551d MD5 | raw file
1indexing 2 description: "Graphics Contexts -- Objects to encapsulate drawing properties" 3 copyright: "[ 4 Copyright (C) 2006 eiffel-libraries team, GTK+ team 5 6 This library is free software; you can redistribute it and/or 7 modify it under the terms of the GNU Lesser General Public License 8 as published by the Free Software Foundation; either version 2.1 of 9 the License, or (at your option) any later version. 10 11 This library is distributed in the hope that it will be useful, but 12 WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 Lesser General Public License for more details. 15 16 You should have received a copy of the GNU Lesser General Public 17 License along with this library; if not, write to the Free Software 18 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 19 02110-1301 USA 20 ]" 21 22 -- All drawing operations in GDK take a graphics context (GC) argument. 23 -- A graphics context encapsulates information about the way things are drawn, 24 -- such as the foreground color or line width. By using graphics contexts, the 25 -- number of arguments to each drawing call is greatly reduced, and 26 -- communication overhead is minimized, since identical arguments do not need 27 -- to be passed repeatedly. 28 -- 29 -- Most values of a graphics context can be set at creation time by using 30 -- create gc.with_values() (NOT IMPLEMENTED), or can be set one-by-one using 31 -- functions such as gc.set_foreground(). A few of the values in the GC, 32 -- such as the dash pattern, can only be set by the latter method. 33 34class GDK_GC 35 36inherit 37 G_OBJECT 38 39insert 40 GDK_GC_EXTERNALS 41 42creation from_external_pointer, make 43 44feature {} -- Creation 45 46 make (a_drawable: GDK_DRAWABLE) is 47 -- Create a new graphics context with default values. 48 do 49 from_external_pointer (gdk_gc_new (a_drawable.handle)) 50 end 51 52feature -- size 53 54 struct_size: INTEGER is 55 external "C inline use <gtk/gtk.h>" 56 alias "sizeof(GdkGc)" 57 end 58 59feature -- Operations 60 61 set_rgb_fg_color (a_color: GDK_COLOR) is 62 -- Set the foreground color of a GC using an unallocated color. 63 -- The pixel value for the color will be determined using GdkRGB. 64 -- If the colormap for the GC has not previously been initialized 65 -- for GdkRGB, then for pseudo-color colormaps (colormaps with a 66 -- small modifiable number of colors), a colorcube will be 67 -- allocated in the colormap. 68 -- 69 -- Calling this function for a GC without a colormap is an error. 70 do 71 gdk_gc_set_rgb_fg_color (handle, a_color.handle) 72 end 73 74 set_rgb_bg_color (a_color: GDK_COLOR) is 75 -- Set the background color of a GC using an unallocated color. 76 -- The pixel value for the color will be determined using GdkRGB. 77 -- If the colormap for the GC has not previously been initialized 78 -- for GdkRGB, then for pseudo-color colormaps (colormaps with a 79 -- small modifiable number of colors), a colorcube will be 80 -- allocated in the colormap. 81 -- 82 -- Calling this function for a GC without a colormap is an error. 83 do 84 gdk_gc_set_rgb_bg_color (handle, a_color.handle) 85 end 86 87end