Number: 546

Date:  6-Apr-84 13':06':04

Submitter: Sannella.PA

Source: JONL.pa

Subject: CLEAR doesn''t always clear bottom line of borderless window

Lisp Version: 

Description: '
Date':  5 APR 84 23':06 PST'
From': JONL.PA'
Subject': failure to clear bottom line of a WINDOW'
To':   LispSupport'
'
I have a borderless window, into which I scribbled some stuff with PAINT'
(from the window menu); then I used CLEAR (again from menu) to clear the window.'
But frequently -- roughly 50% of the time -- the pixels on the absolute bottom'
line aren''t cleared.'
'
Sorry, I can''t seem to see any other relevant clues.'
'
-----'
'
Date':  6 Apr 84 15':33 PST'
From': Burton.pa'
Subject': Re': AR 546': CLEAR doesn''t always clear bottom line of borderless window'
In-reply-to': LispSupport.pa''s message of 6 Apr 84 13':06':28 PST (Friday)'
To': LispSupport.pa'
cc': Jonl.pa'
'
I''ve tried several ways of reproducing it and haven''t been able to.  Where you changing the DSPCLIPPINGREGION of the window?  '
'
Let me know if it happens again.'
'
richard'
'
-----'
'
Date':  9 APR 84 19':21 PST'
From': JONL.PA'
Subject': Re': AR 546': CLEAR doesn''t always clear bottom line of borderless window'
To':   Burton, LispSupport'
cc':   Jonl'
'
In response to the message sent   6 Apr 84 15':33 PST from Burton.pa'
'
No, I never mucked with DSPCLIPPINGREGION -- simply had created a borderless'
window into which I "painted" some bits, and then used windowMenu com "Clear"'
to try to reset the window.'
'
I had, however, scrolled the window up from time to time, using the "cached"'
pilot bitblt table.  Nevertheless, the lossages occurred in between scrollings,'
and didn''t seem to be connected with them.'
'
I believe i had called SHAPEW to place the window''s bottom line on line 16'
of the SCREENBITMAP (Which probably shouldn''t make any difference but . . .)'
'
-----'
'
Date': 10 Apr 84 10':35 PST'
From': Burton.pa'
Subject': Re': AR 546': CLEAR doesn''t always clear bottom line of borderless window'
In-reply-to': JONL.PA''s message of 9 APR 84 19':21 PST'
To': JONL.PA'
cc': Burton.PA, LispSupport.PA'
'
There was a bug in the caret code for a few days that put bits in the border region of the window.  These would not be cleared by CLEARW.  Could this have been what you noticed?'
'
richard'
'
Date': 10 APR 84 16':04 PST'
From': JONL.PA'
Subject': Re': AR 546': CLEAR doesn''t always clear bottom line of borderless window'
To':   Burton, JONL'
cc':   LispSupport'
'
In response to the message sent  10 Apr 84 10':35 PST from Burton.pa'
'
Nope, not that one either.  I never made this borderless window a TTYDISPLAYSTREAM for anyone.  Only got the bits there via Paint window command and bitbltting the whole region of the screen up by one pixel -- i.e., the scrolling test passed along by Peter.  However, the lossage was noticeable after doing a successfule Clear command, and just painting, and trying Clear again.'
'


Workaround: 

Test Case: 

Edit-By: masinter.PA

Edit-Date: 11-Apr-84 15':41':04

Attn: Burton.pa

Assigned To: 

In/By: 

Disposition: 

System: Windows and Graphics

Subsystem: Window System

Machine: 

Disk: 

Microcode Version: 

Memory Size: 

File Server: 

Server Software Version: 

Difficulty: 

Frequency: Intermittent

Impact: Annoying

Priority: Perhaps

Status: Open

Problem Type: Bug

Source Files: