; docformat = 'rst' ; ; NAME: ; cgErase ; ; PURPOSE: ; Provides a device-independent and color-model-independent way to erase a graphics ; window with a particular color. ; ;******************************************************************************************; ; ; ; Copyright (c) 2010, by Fanning Software Consulting, Inc. All rights reserved. ; ; ; ; Redistribution and use in source and binary forms, with or without ; ; modification, are permitted provided that the following conditions are met: ; ; ; ; * Redistributions of source code must retain the above copyright ; ; notice, this list of conditions and the following disclaimer. ; ; * Redistributions in binary form must reproduce the above copyright ; ; notice, this list of conditions and the following disclaimer in the ; ; documentation and/or other materials provided with the distribution. ; ; * Neither the name of Fanning Software Consulting, Inc. nor the names of its ; ; contributors may be used to endorse or promote products derived from this ; ; software without specific prior written permission. ; ; ; ; THIS SOFTWARE IS PROVIDED BY FANNING SOFTWARE CONSULTING, INC. ''AS IS'' AND ANY ; ; EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES ; ; OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT ; ; SHALL FANNING SOFTWARE CONSULTING, INC. BE LIABLE FOR ANY DIRECT, INDIRECT, ; ; INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED ; ; TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; ; ; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ; ; ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ; ; (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS ; ; SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. ; ;******************************************************************************************; ; ;+ ; Provides a device-independent and color-model-independent way to erase a graphics ; window with a particular color. ; ; :Categories: ; Graphics ; ; :Params: ; background_color: in, optional, type=string/integer/long, default='white' ; The color to use in erasing the graphics window. Default is "white." ; Color names are those used with cgColor. ; ; :Keywords: ; color: in, optional, type=string/integer/long, default='white' ; An alternative way to specify the color to use in erasing the graphics window. ; Color names are those used with cgColor. This parameter is used in ; preference to the background_color parameter. ; layout: in, optional, type=intarr(3) ; This keyword specifies a grid with a graphics window and determines where the ; graphic should appear. The syntax of LAYOUT is three numbers: [ncolumns, nrows, location]. ; The grid is determined by the number of columns (ncolumns) by the number of ; rows (nrows). The location of the graphic is determined by the third number. The ; grid numbering starts in the upper left (1) and goes sequentually by column and then ; by row. If this keyword is used, only this portion of the window is erased. ; window: in, optional, type=boolean, default=0 ; Set this keyword to erase the current cgWindow application. "Erasing" in ; this case means removing all the current commands. ; ; :Examples: ; Used to "erase" various things:: ; IDL> cgErase ; IDL> cgErase, 'gray' ; IDL> cgErase, COLOR='charcoal' ; ; IDL> cgPlot, cgDemoData(1), /Window ; IDL> cgErase, /Window ; ; IDL> cgPlot, cgDemoData(17), Layout=[2,2,1] ; IDL> cgPlot, cgDemoData(17), Layout=[2,2,4] ; IDL> cgErase, Layout=[2,2,1] ; ; :Author: ; FANNING SOFTWARE CONSULTING:: ; David W. Fanning ; 1645 Sheely Drive ; Fort Collins, CO 80526 USA ; Phone: 970-221-0438 ; E-mail: david@idlcoyote.com ; Coyote's Guide to IDL Programming: http://www.idlcoyote.com ; ; :History: ; Change History:: ; Written, 12 November 2010. DWF. ; Modified so that input variables are not changed. 18 Nov 2010. DWF. ; Got my color selection algorithm right. COLOR keyword takes precedence ; over the parameter. 18 Nov 2010. DWF. ; Modified to erase in decomposed color, if possible. ; In some cases, I was turning BYTE values to strings without converting to ; INTEGERS first. 30 Dec 2010. DWF. ; Added WINDOW keyword. 26 Jan 2011. DWF. ; Added LAYOUT keyword. 1 Feb 2011. DWF. ; Modified error handler to restore the entry decomposition state if there is an error. 17 March 2011. DWF ; ; :Copyright: ; Copyright (c) 2010, Fanning Software Consulting, Inc. ;- PRO cgErase, background_color, COLOR=color, LAYOUT=layout, WINDOW=window Catch, theError IF theError NE 0 THEN BEGIN Catch, /Cancel IF N_Elements(currentState) NE 0 THEN cgSetColorState, currentState RETURN ENDIF ; Are we erasing an cgWindow application? IF Keyword_Set(window) THEN BEGIN currentID = cgQuery(COUNT=wincnt, OBJECTREF=currentObj, /Current) IF wincnt GT 0 THEN BEGIN currentObj -> DeleteCommand, /All currentObj -> ExecuteCommands ENDIF RETURN ENDIF ; Set up PostScript device for working with colors. IF !D.Name EQ 'PS' THEN Device, COLOR=1, BITS_PER_PIXEL=8 ; Get a color for erasing. IF N_Elements(background_color) EQ 0 THEN thisColor = 'white' ELSE thisColor = background_color IF N_Elements(color) NE 0 THEN thisColor = color IF Size(thisColor, /TYPE) EQ 3 THEN IF cgGetColorState() EQ 0 THEN thisColor = Byte(thisColor) IF Size(thisColor, /TYPE) LE 2 THEN thisColor = StrTrim(Fix(thisColor),2) ; Get the current color vectors. TVLCT, rr, gg, bb, /Get ; Do this in decomposed color, if possible. cgSetColorState, 1, CURRENTSTATE=currentState IF Size(thisColor, /TNAME) EQ 'STRING' THEN thisColor = cgColor(thisColor) ; Set up the layout, if necessary. IF N_Elements(layout) NE 0 THEN BEGIN thisMulti = !P.Multi totalPlots = layout[0]*layout[1] !P.Multi = [0,layout[0], layout[1], 0, 0] IF layout[2] EQ 1 THEN BEGIN noerase = 1 !P.Multi[0] = 0 ENDIF ELSE BEGIN !P.Multi[0] = totalPlots - layout[2] + 1 ENDELSE ; Draw an invisible plot in this space. Plot, [0,1], XStyle=4, YStyle=4, /NoErase ; Fill the plot area with the color. x = !X.Region y = !Y.Region PolyFill, [x[0], x[0], x[1], x[1]], $ [y[0], y[1], y[1], y[0]], /FIll, $ Color=thisColor, /Normal !P.Multi = thisMulti ENDIF ELSE Erase, thisColor ; Clean up. cgSetColorState, currentState IF !D.Name NE 'Z' THEN TVLCT, rr, gg, bb END