Re: [lazarus] Reducing Flickeron a TImage component
The disabled TBitBtn flickers, because the grayed image is created during paint. TSpeedButton does not gray the image, but paints delayed (gtk1 intf). So it might flicker less for small buttons. Aaaah, okay, that explains it - but also means it won't work for me. The 'grayed' effect is fairly fundamental to the usability of the app. Also - these are not small buttons :) the glyphs are about 128x128 each. A.J. -- A.J. Venter CEO - OutKast Solutions C.C. http://www.outkastsolutions.co.za Cell: +27 83 455 9978 Fax: +27 21 413 2800 Office: +27 21 591 6766 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
On Thu, 31 May 2007 09:14:52 +0200 A.J. Venter [EMAIL PROTECTED] wrote: The disabled TBitBtn flickers, because the grayed image is created during paint. TSpeedButton does not gray the image, but paints delayed (gtk1 intf). So it might flicker less for small buttons. Aaaah, okay, that explains it - but also means it won't work for me. The 'grayed' effect is fairly fundamental to the usability of the app. You can 'gray' it yourself. Also - these are not small buttons :) the glyphs are about 128x128 each. That's not very big. It should flicker less. Mattias _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
It seems, gtk_pixmap is creating the disabled image on-the-fly on first paint. So, the flickering is built-in. Because you change the image often, you see it often. Conclusion: gtk1+TBitBtn+disabled = flicker So the short version is - that GTK1 couldn't do what I needed (a dynamically updated but often disabled set of buttons with pictures on them) without creating a new component. It turned out to be far less work to just port this part of the program to GTK2, the rest remains GTK1 for now (there are three apps that make up the suite here) simply because fixing all the layouts etc. for GTK2 would take a LONG time (and worst of all GTK2 is still horrible with Z-order handling) but this part works just fine under GTK2 - and as per your predictions, the GTK2 version is completely flicker free. For the next OutKafe release (which I will start on after I return from this project on Friday) I will port it to GTK2 in it's entirety (it can be done now that SetWindowFulScreen works for GTK2) however. A.J. -- A.J. Venter CEO - OutKast Solutions C.C. http://www.outkastsolutions.co.za Cell: +27 83 455 9978 Fax: +27 21 413 2800 Office: +27 21 591 6766 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
On Wed, 30 May 2007 10:34:45 +0200 A.J. Venter [EMAIL PROTECTED] wrote: It seems, gtk_pixmap is creating the disabled image on-the-fly on first paint. So, the flickering is built-in. Because you change the image often, you see it often. Conclusion: gtk1+TBitBtn+disabled = flicker So the short version is - that GTK1 couldn't do what I needed (a dynamically updated but often disabled set of buttons with pictures on them) without creating a new component. Maybe you can try TSpeedButton instead of TBitBtn. It turned out to be far less work to just port this part of the program to GTK2, the rest remains GTK1 for now (there are three apps that make up the suite here) simply because fixing all the layouts etc. for GTK2 would take a LONG time (and worst of all GTK2 is still horrible with Z-order handling) but this part works just fine under GTK2 - and as per your predictions, the GTK2 version is completely flicker free. For the next OutKafe release (which I will start on after I return from this project on Friday) I will port it to GTK2 in it's entirety (it can be done now that SetWindowFulScreen works for GTK2) however. A.J. The gtk2 intf is currently under heavy development. This can be good or bad for your project. Mattias _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
gtk1+TBitBtn+disabled = flicker So the short version is - that GTK1 couldn't do what I needed (a dynamically updated but often disabled set of buttons with pictures on them) without creating a new component. Maybe you can try TSpeedButton instead of TBitBtn. That would only work if I painted the Caption myself would it not ? In which case... it gets even MORE custom painting... not sure it's worth it. For the next OutKafe release (which I will start on after I return from this project on Friday) I will port it to GTK2 in it's entirety (it can be done now that SetWindowFulScreen works for GTK2) however. A.J. The gtk2 intf is currently under heavy development. This can be good or bad for your project. For OutKafe it's probably a good thing, for CAN it's less good as stability is more important and this is just phase1 of a large multiphase project that will take many more months if not years to finish. That is the major reason I ONLY migrated the admin console despite the fact that the client could work too, it reduces the impact of unexpected changes in the gtk2 interface. Appart from the dynamic bitbuttons, it's really a pretty simple interface so it works fine. Ciao A.J. -- A.J. Venter CEO - OutKast Solutions C.C. http://www.outkastsolutions.co.za Cell: +27 83 455 9978 Fax: +27 21 413 2800 Office: +27 21 591 6766 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
On Wed, 30 May 2007 13:56:55 +0200 A.J. Venter [EMAIL PROTECTED] wrote: gtk1+TBitBtn+disabled = flicker So the short version is - that GTK1 couldn't do what I needed (a dynamically updated but often disabled set of buttons with pictures on them) without creating a new component. Maybe you can try TSpeedButton instead of TBitBtn. That would only work if I painted the Caption myself would it not ? TSpeedButton has a Caption. Default is ''. In which case... it gets even MORE custom painting... not sure it's worth it. Did you try? For the next OutKafe release (which I will start on after I return from this project on Friday) I will port it to GTK2 in it's entirety (it can be done now that SetWindowFulScreen works for GTK2) however. A.J. The gtk2 intf is currently under heavy development. This can be good or bad for your project. For OutKafe it's probably a good thing, for CAN it's less good as stability is more important and this is just phase1 of a large multiphase project that will take many more months if not years to finish. That is the major reason I ONLY migrated the admin console despite the fact that the client could work too, it reduces the impact of unexpected changes in the gtk2 interface. Appart from the dynamic bitbuttons, it's really a pretty simple interface so it works fine. Mattias _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
Maybe you can try TSpeedButton instead of TBitBtn. That would only work if I painted the Caption myself would it not ? TSpeedButton has a Caption. Default is ''. In which case... it gets even MORE custom painting... not sure it's worth it. Did you try? Heh, point made :) Question then: so what IS the difference between TBitBtn and TSpeedButton ? In general, but also specifially before it's worth trying, it's worth knowing if their disabled paint code are in fact different. A.J. -- A.J. Venter CEO - OutKast Solutions C.C. http://www.outkastsolutions.co.za Cell: +27 83 455 9978 Fax: +27 21 413 2800 Office: +27 21 591 6766 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
On Wed, 30 May 2007 22:17:57 +0200 A.J. Venter [EMAIL PROTECTED] wrote: Maybe you can try TSpeedButton instead of TBitBtn. That would only work if I painted the Caption myself would it not ? TSpeedButton has a Caption. Default is ''. In which case... it gets even MORE custom painting... not sure it's worth it. Did you try? Heh, point made :) Question then: so what IS the difference between TBitBtn and TSpeedButton ? In general, but also specifially before it's worth trying, it's worth knowing if their disabled paint code are in fact different. The disabled TBitBtn flickers, because the grayed image is created during paint. TSpeedButton does not gray the image, but paints delayed (gtk1 intf). So it might flicker less for small buttons. Mattias _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
An updated (related) question would be whether there is any way to remove the flicker in THIS case: I have a couple of TBitBtn components. Appart from their captions and glyphs, I actually write some information to the canvasses which are meant to show up ON TOP of each glyph. A button may or may not contain info/may or may not currently be enabled ( these buttons represent actual computer terminals in the real world, and are updated based on what those terminals store in a database - when somebody logs into a terminal, the corresponding button should display his info and be enabled). The procedures I have for either updating or disabling buttons are below. A TTimer checks the database every second and then runs either UpdateBtn or ButtonOff depending on the particular button's current state. It all works quite well... (although before adding invalidates to each procedure it had a tendency to lose the caption) ... except it flickers something awful. Since I have no desire to cause massive epilepsy among my users, I would appreciate some advice here (this is a trickier one.. after all how do you double buffer a BUTTON ?) A.J. Procedure UpdateBtn(Button:TBitBtn;UserName,Time,Status:String); Begin Button.Glyph.Canvas.Clear; Button.Glyph.Assign(NewMainForm.Image1.Picture); Button.Glyph.Canvas.Font.Size := 18; Button.Glyph.Canvas.Font.Name := 'times'; Button.Glyph.Canvas.Font.Color := ClBlue; Button.Glyph.Canvas.TextOut(20,20,'User: '+Username); Button.Hint := UserName; Button.Glyph.Canvas.TextOut(20,50,'Time: '+Time); Button.Glyph.Canvas.TextOut(20,80,'Status: '+Status); Button.Invalidate; End; Procedure ButtonOff(Button:TbitBtn); Begin Button.Glyph.Canvas.Clear; Button.Glyph.Assign(NewMainForm.Image1.Picture); Button.Enabled := False; Button.Invalidate;; end; On 5/28/07, Dave Coventry [EMAIL PROTECTED] wrote: Gustavo, My problem was caused by the fact that the background for my TImage was black. When I placed it on a black-coloured panel (I used a TScrollBox as I want to capture mousewheel events), I found the flicker was more or less unoticeable. Gustavo Enrique Jimenez wrote: 2007/5/28, Dave Coventry [EMAIL PROTECTED] mailto:[EMAIL PROTECTED]: Gustavo Enrique Jimenez wrote: There are good tutorials/examples on http://wiki.lazarus.freepascal.org/Developing_with_Graphics http://wiki.lazarus.freepascal.org/Developing_with_Graphics http://wiki.lazarus.freepascal.org/Developing_with_Graphics Gustavo, Thank you for your reply. But they don't really help. Do you draw a line to the Image1.Canvas? or do you draw to Image1.Picture.Bitmap.Canvas as suggested by the wiki? Which seems to make the flickering worse? Or do you need to suspend onPaint until you've finished drawing? In which case, how do you suspend onPaint? I have used the Create a custom control which draws itself method, and it worked very well !! Try this method. Gustavo ps: for the record, Felipe Monteiro help me A LOT in private mails. Thanks Felipe, and excuse me for bother you in private. -- Dave Coventry Tel (home): +27(0)31 3092301 Tel (office): +27(0)31 2058448 Cell: +27(0)82 9000179 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives -- A.J. Venter CEO - OutKast Solutions C.C. http://www.outkastsolutions.co.za Cell: +27 83 455 9978 Fax: +27 21 413 2800 Office: +27 21 591 6766 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
On 5/29/07, Felipe Monteiro de Carvalho [EMAIL PROTECTED] wrote: On 5/29/07, A.J. Venter [EMAIL PROTECTED] wrote: I have a couple of TBitBtn components. Appart from their captions and glyphs, I actually write some information to the canvasses which are meant to show up ON TOP of each glyph. I would write my own fully custom-drawn button to do this. I was afraid you'd say that :) Now imagine my deadline is a few hours only and I have other outstanding functionality to code... A.J. _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
AJ, In my case, when the image is redrawn, the TImage was cleared which showed the underlying colour (clBtnFace), which caused the flicker when the black background was painted in. I'm not sure of how relevant it would be in your case, but I changed the colour of the underlying panel to black, which eliminated the flicker. It would depend, I guess, on the colour of your graphic and the colour of the background displayed when it clears. (I'm not really auf fe with the TBitBtn components, having never used them). A.J. Venter wrote: On 5/29/07, Felipe Monteiro de Carvalho [EMAIL PROTECTED] wrote: On 5/29/07, A.J. Venter [EMAIL PROTECTED] wrote: I have a couple of TBitBtn components. Appart from their captions and glyphs, I actually write some information to the canvasses which are meant to show up ON TOP of each glyph. I would write my own fully custom-drawn button to do this. I was afraid you'd say that :) Now imagine my deadline is a few hours only and I have other outstanding functionality to code... A.J. _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives -- Dave Coventry Tel (home): +27(0)31 3092301 Tel (office): +27(0)31 2058448 Cell: +27(0)82 9000179 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
Well I've reduced the flicker a little by doing a few small things (mostly not reloading images unless they have changed). I also set the DoubleBuffered property of the components to true, though I see no effect from doing so nor do I know what effect it's supposed to have. My understanding of doublebuffering (as I learned it doing things like SDL) is that it means that any changes to the component/canvas is drawn in memory NOT on screen, and only when they are all done do you update the component with one single action (drawing the memory buffer to the screen buffer - known commonly as a 'flip') - my TDoubleBuffer component is based on doing exactly that. What it means when you set the doublebuffered property of a button to true I don't know - though I would love to find out. A.J. On 5/29/07, Dave Coventry [EMAIL PROTECTED] wrote: AJ, In my case, when the image is redrawn, the TImage was cleared which showed the underlying colour (clBtnFace), which caused the flicker when the black background was painted in. I'm not sure of how relevant it would be in your case, but I changed the colour of the underlying panel to black, which eliminated the flicker. It would depend, I guess, on the colour of your graphic and the colour of the background displayed when it clears. (I'm not really auf fe with the TBitBtn components, having never used them). A.J. Venter wrote: On 5/29/07, Felipe Monteiro de Carvalho [EMAIL PROTECTED] wrote: On 5/29/07, A.J. Venter [EMAIL PROTECTED] wrote: I have a couple of TBitBtn components. Appart from their captions and glyphs, I actually write some information to the canvasses which are meant to show up ON TOP of each glyph. I would write my own fully custom-drawn button to do this. I was afraid you'd say that :) Now imagine my deadline is a few hours only and I have other outstanding functionality to code... A.J. _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives -- Dave Coventry Tel (home): +27(0)31 3092301 Tel (office): +27(0)31 2058448 Cell: +27(0)82 9000179 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives -- A.J. Venter CEO - OutKast Solutions C.C. http://www.outkastsolutions.co.za Cell: +27 83 455 9978 Fax: +27 21 413 2800 Office: +27 21 591 6766 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
On Tue, 29 May 2007 11:26:02 +0200 A.J. Venter [EMAIL PROTECTED] wrote: Well I've reduced the flicker a little by doing a few small things (mostly not reloading images unless they have changed). I also set the DoubleBuffered property of the components to true, though I see no effect from doing so nor do I know what effect it's supposed to have. My understanding of doublebuffering (as I learned it doing things like SDL) is that it means that any changes to the component/canvas is drawn in memory NOT on screen, and only when they are all done do you update the component with one single action (drawing the memory buffer to the screen buffer - known commonly as a 'flip') - my TDoubleBuffer component is based on doing exactly that. What it means when you set the doublebuffered property of a button to true I don't know - though I would love to find out. DoubleBuffered is a hint for the interface. The gtk2 intf always paints double buffered for each gdkwindow. That means paint events are double buffered, other painting not. The gtk1 intf has almost no doublebuffering. I'm not sure about the other interfaces. I only did a small test: The gtk intf only paints once per Invalidate and there I see no flicker at all. That's because the bitbtn glyph handle is a memory handle and not an image on the screen. Maybe the win32 intf is creating a screen handle? That would explain the flickering. Mattias A.J. On 5/29/07, Dave Coventry [EMAIL PROTECTED] wrote: AJ, In my case, when the image is redrawn, the TImage was cleared which showed the underlying colour (clBtnFace), which caused the flicker when the black background was painted in. I'm not sure of how relevant it would be in your case, but I changed the colour of the underlying panel to black, which eliminated the flicker. It would depend, I guess, on the colour of your graphic and the colour of the background displayed when it clears. (I'm not really auf fe with the TBitBtn components, having never used them). A.J. Venter wrote: On 5/29/07, Felipe Monteiro de Carvalho [EMAIL PROTECTED] wrote: On 5/29/07, A.J. Venter [EMAIL PROTECTED] wrote: I have a couple of TBitBtn components. Appart from their captions and glyphs, I actually write some information to the canvasses which are meant to show up ON TOP of each glyph. I would write my own fully custom-drawn button to do this. I was afraid you'd say that :) Now imagine my deadline is a few hours only and I have other outstanding functionality to code... A.J. _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives -- Dave Coventry Tel (home): +27(0)31 3092301 Tel (office): +27(0)31 2058448 Cell: +27(0)82 9000179 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
DoubleBuffered is a hint for the interface. The gtk2 intf always paints double buffered for each gdkwindow. That means paint events are double buffered, other painting not. The gtk1 intf has almost no doublebuffering. I'm not sure about the other interfaces. Aaah okay, that makes sense. I only did a small test: The gtk intf only paints once per Invalidate and there I see no flicker at all. That's because the bitbtn glyph handle is a memory handle and not an image on the screen. Maybe the win32 intf is creating a screen handle? That would explain the flickering. This is a GTK1 app. The catch is that if I don't call invalidate, the buttons go entirely blank instead of merely being grayed out, this includes the captions. If I DO call invalidate, I end up with a whole LOT of repaints all the time - which is... well ugly to say the least. I am still not sure how best to approach this. Shouldn't the buttons remain in their last state, repainted when damaged until such time as they are changed ? I'm not even moving anything here just painting some info onto SOME of the buttons and updating those periodically while setting the others disabled until such time as they are in use. And it's the DISABLED buttons which are giving me grief, the enabled once have a very slight flicker but it's actually almost nothing (again I don't know why that would be). -- A.J. Venter CEO - OutKast Solutions C.C. http://www.outkastsolutions.co.za Cell: +27 83 455 9978 Fax: +27 21 413 2800 Office: +27 21 591 6766 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
Hi, I am just making a wild guess, so if it sounds absurd, please ignore. :-) How about creating a dummy invisible button, and use that one as a buffer for all the other buttons. So, everytime you need to update a button, rather make the dummy what you want, then somehow copy the canvas of the dummy into the canvas of the actual button. I think if this would work it will eliminate flicker and shouldn't be too much overhead. Charl On 5/29/07, A.J. Venter [EMAIL PROTECTED] wrote: DoubleBuffered is a hint for the interface. The gtk2 intf always paints double buffered for each gdkwindow. That means paint events are double buffered, other painting not. The gtk1 intf has almost no doublebuffering. I'm not sure about the other interfaces. Aaah okay, that makes sense. I only did a small test: The gtk intf only paints once per Invalidate and there I see no flicker at all. That's because the bitbtn glyph handle is a memory handle and not an image on the screen. Maybe the win32 intf is creating a screen handle? That would explain the flickering. This is a GTK1 app. The catch is that if I don't call invalidate, the buttons go entirely blank instead of merely being grayed out, this includes the captions. If I DO call invalidate, I end up with a whole LOT of repaints all the time - which is... well ugly to say the least. I am still not sure how best to approach this. Shouldn't the buttons remain in their last state, repainted when damaged until such time as they are changed ? I'm not even moving anything here just painting some info onto SOME of the buttons and updating those periodically while setting the others disabled until such time as they are in use. And it's the DISABLED buttons which are giving me grief, the enabled once have a very slight flicker but it's actually almost nothing (again I don't know why that would be). -- A.J. Venter CEO - OutKast Solutions C.C. http://www.outkastsolutions.co.za Cell: +27 83 455 9978 Fax: +27 21 413 2800 Office: +27 21 591 6766 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives -- I love deadlines. I especially love the whooshing sound they make as they fly by. - Douglas Adams
Re: [lazarus] Reducing Flickeron a TImage component
Zitat von A.J. Venter [EMAIL PROTECTED]: DoubleBuffered is a hint for the interface. The gtk2 intf always paints double buffered for each gdkwindow. That means paint events are double buffered, other painting not. The gtk1 intf has almost no doublebuffering. I'm not sure about the other interfaces. Aaah okay, that makes sense. I only did a small test: The gtk intf only paints once per Invalidate and there I see no flicker at all. That's because the bitbtn glyph handle is a memory handle and not an image on the screen. Maybe the win32 intf is creating a screen handle? That would explain the flickering. This is a GTK1 app. The catch is that if I don't call invalidate, the buttons go entirely blank instead of merely being grayed out, this includes the captions. If I DO call invalidate, I end up with a whole LOT of repaints all the time - which is... well ugly to say the least. I am still not sure how best to approach this. Shouldn't the buttons remain in their last state, repainted when damaged until such time as they are changed ? I'm not even moving anything here just painting some info onto SOME of the buttons and updating those periodically while setting the others disabled until such time as they are in use. And it's the DISABLED buttons which are giving me grief, the enabled once have a very slight flicker but it's actually almost nothing (again I don't know why that would be). I can reproduce the issue: gtk1 with enabled=false TBitBtn. I wonder, why only the flickering is only visible with a disabled bitbtn ... Mattias -- A.J. Venter CEO - OutKast Solutions C.C. http://www.outkastsolutions.co.za Cell: +27 83 455 9978 Fax: +27 21 413 2800 Office: +27 21 591 6766 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives -- Powered by NetMail _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
I used TPaintBox... it's work better than Timage when Drawing (OnPaint) You can try it Gustavo Enrique Jimenez [EMAIL PROTECTED] wrote: 2007/5/28, Dave Coventry [EMAIL PROTECTED]: Gustavo Enrique Jimenez wrote: There are good tutorials/examples on http://wiki.lazarus.freepascal.org/Developing_with_Graphics http://wiki.lazarus.freepascal.org/Developing_with_Graphics Gustavo, Thank you for your reply. But they don't really help. Do you draw a line to the Image1.Canvas? or do you draw to Image1.Picture.Bitmap.Canvas as suggested by the wiki? Which seems to make the flickering worse? Or do you need to suspend onPaint until you've finished drawing? In which case, how do you suspend onPaint? I have used the Create a custom control which draws itself method, and it worked very well !! Try this method. Gustavo ps: for the record, Felipe Monteiro help me A LOT in private mails. Thanks Felipe, and excuse me for bother you in private. =INTOSOFT ALEXIO CHAOS [EMAIL PROTECTED] Yahoo Messager = - Need a vacation? Get great deals to amazing places on Yahoo! Travel.
Re: [lazarus] Reducing Flickeron a TImage component
On Tue, 29 May 2007 15:11:48 +0200 Mattias Gärtner [EMAIL PROTECTED] wrote: Zitat von A.J. Venter [EMAIL PROTECTED]: DoubleBuffered is a hint for the interface. The gtk2 intf always paints double buffered for each gdkwindow. That means paint events are double buffered, other painting not. The gtk1 intf has almost no doublebuffering. I'm not sure about the other interfaces. Aaah okay, that makes sense. I only did a small test: The gtk intf only paints once per Invalidate and there I see no flicker at all. That's because the bitbtn glyph handle is a memory handle and not an image on the screen. Maybe the win32 intf is creating a screen handle? That would explain the flickering. This is a GTK1 app. The catch is that if I don't call invalidate, the buttons go entirely blank instead of merely being grayed out, this includes the captions. If I DO call invalidate, I end up with a whole LOT of repaints all the time - which is... well ugly to say the least. I am still not sure how best to approach this. Shouldn't the buttons remain in their last state, repainted when damaged until such time as they are changed ? I'm not even moving anything here just painting some info onto SOME of the buttons and updating those periodically while setting the others disabled until such time as they are in use. And it's the DISABLED buttons which are giving me grief, the enabled once have a very slight flicker but it's actually almost nothing (again I don't know why that would be). I can reproduce the issue: gtk1 with enabled=false TBitBtn. I wonder, why only the flickering is only visible with a disabled bitbtn ... It seems, gtk_pixmap is creating the disabled image on-the-fly on first paint. So, the flickering is built-in. Because you change the image often, you see it often. Conclusion: gtk1+TBitBtn+disabled = flicker Mattias _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
[lazarus] Reducing Flickeron a TImage component
I'm getting an awful lot of screen flicker from the following code: == snip Form1.Image1.Canvas.Pen.Color:=$FF; Form1.Image1.Canvas.Pen.Mode:=pmNot; Form1.Image1.Canvas.MoveTo(iCornerX,CornerY); Form1.Image1.Canvas.LineTo(PrevX,PrevY); Form1.Image1.Canvas.MoveTo(iCornerX,CornerY); Form1.Image1.Canvas.LineTo(X,Y); == snip It's actually rubberbanding showing where a line will be drawn. Is there a way of reducing this? The background colour of the TImage is black which tends to accentuate it somewhat. -- Dave Coventry Tel (home): +27(0)31 3092301 Tel (office): +27(0)31 2058448 Cell: +27(0)82 9000179 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
Hi I'm getting an awful lot of screen flicker from the following code: == snip Form1.Image1.Canvas.Pen.Color:=$FF; Form1.Image1.Canvas.Pen.Mode:=pmNot; Form1.Image1.Canvas.MoveTo(iCornerX,CornerY); Form1.Image1.Canvas.LineTo(PrevX,PrevY); Form1.Image1.Canvas.MoveTo(iCornerX,CornerY); Form1.Image1.Canvas.LineTo(X,Y); == snip It's actually rubberbanding showing where a line will be drawn. Is there a way of reducing this? The background colour of the TImage is black which tends to accentuate it somewhat. -- There are good tutorials/examples on http://wiki.lazarus.freepascal.org/Developing_with_Graphics Gustavo
Re: [lazarus] Reducing Flickeron a TImage component
Gustavo Enrique Jimenez wrote: There are good tutorials/examples on http://wiki.lazarus.freepascal.org/Developing_with_Graphics http://wiki.lazarus.freepascal.org/Developing_with_Graphics Gustavo, Thank you for your reply. But they don't really help. Do you draw a line to the Image1.Canvas? or do you draw to Image1.Picture.Bitmap.Canvas as suggested by the wiki? Which seems to make the flickering worse? Or do you need to suspend onPaint until you've finished drawing? In which case, how do you suspend onPaint? -- Dave Coventry Tel (home): +27(0)31 3092301 Tel (office): +27(0)31 2058448 Cell: +27(0)82 9000179 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
2007/5/28, Dave Coventry [EMAIL PROTECTED]: Gustavo Enrique Jimenez wrote: There are good tutorials/examples on http://wiki.lazarus.freepascal.org/Developing_with_Graphics http://wiki.lazarus.freepascal.org/Developing_with_Graphics Gustavo, Thank you for your reply. But they don't really help. Do you draw a line to the Image1.Canvas? or do you draw to Image1.Picture.Bitmap.Canvas as suggested by the wiki? Which seems to make the flickering worse? Or do you need to suspend onPaint until you've finished drawing? In which case, how do you suspend onPaint? I have used the Create a custom control which draws itself method, and it worked very well !! Try this method. Gustavo ps: for the record, Felipe Monteiro help me A LOT in private mails. Thanks Felipe, and excuse me for bother you in private.
Re: [lazarus] Reducing Flickeron a TImage component
On 5/28/07, Gustavo Enrique Jimenez [EMAIL PROTECTED] wrote: ps: for the record, Felipe Monteiro help me A LOT in private mails. Thanks Felipe, and excuse me for bother you in private. No problem =) -- Felipe Monteiro de Carvalho _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] Reducing Flickeron a TImage component
Gustavo, My problem was caused by the fact that the background for my TImage was black. When I placed it on a black-coloured panel (I used a TScrollBox as I want to capture mousewheel events), I found the flicker was more or less unoticeable. Gustavo Enrique Jimenez wrote: 2007/5/28, Dave Coventry [EMAIL PROTECTED] mailto:[EMAIL PROTECTED]: Gustavo Enrique Jimenez wrote: There are good tutorials/examples on http://wiki.lazarus.freepascal.org/Developing_with_Graphics http://wiki.lazarus.freepascal.org/Developing_with_Graphics http://wiki.lazarus.freepascal.org/Developing_with_Graphics Gustavo, Thank you for your reply. But they don't really help. Do you draw a line to the Image1.Canvas? or do you draw to Image1.Picture.Bitmap.Canvas as suggested by the wiki? Which seems to make the flickering worse? Or do you need to suspend onPaint until you've finished drawing? In which case, how do you suspend onPaint? I have used the Create a custom control which draws itself method, and it worked very well !! Try this method. Gustavo ps: for the record, Felipe Monteiro help me A LOT in private mails. Thanks Felipe, and excuse me for bother you in private. -- Dave Coventry Tel (home): +27(0)31 3092301 Tel (office): +27(0)31 2058448 Cell: +27(0)82 9000179 _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
