I am developing a tetris like game in winforms(C# and .netframework 2.0).
The winform has an background image and a picture-box which move down(new Location is assigned) at an interval of 500ms.
The problem is when picture-box moves down the background image of form flickers at the point where the picture-box was earlier located. If i don't use any background image, then there is no flickering.
Is there any graphics accelerator or any kind of solution using which the flickering problem can be solved.
The term used for this is Double Buffering. The idea is simple - start with 2 panes but only display one. Draw to a hidden pane, and quickly swap the hidden and visible panes. Rinse and repeat for every transition (animation).
Luckily, you dont have to deal with the nuts and bolts of this in .NET, controls do it for you. This SO question will help you: How to double buffer .NET controls on a form?
Set DoubleBuffered = true on your controls. This should help prevent flickering.
For documentation on the DoubleBuffered property, see here:
http://msdn.microsoft.com/en-us/library/system.windows.forms.control.doublebuffered.aspx
If you are developing a game in Windows Forms you really ought to be overriding OnPaint and implementing painting of the sprites on every frame, as opposed to moving heavyweight PictureBox controls.
You will find you may get the flicker regardless of DoubleBuffer if you use the approach you mentioned. However, with all drawing done in OnPaint, then DoubleBuffer begins to work.
I did a quick search and found this interesting article on creating a game-loop in Windows Forms using OnPaint override. In particular take a look at GameStateDrawer which does the rendering directly to graphics context.
Related
I'm having this problem. I would like for the frog's background to be transparent so the log underneath can be seen, but instead, the background picturebox's color is shown.
problem
I googled the problem and got the suggestion to change the Parent of the picturebox, which i tried, but this happened:
it works, but only in the log's picturebox area
I'm clearly doing something wrong. Can somebody help?
WinForms does not support true alpha-transparency. "Transparent" controls re-render only the parent form's background behind themselves - controls cannot be truely layered and blended in the Z-axis.
So what you're after really isn't possible.
However, implementing a game using WinForms controls and GDI (System.Drawing) is a bad idea - performance is terrible (in part due to Microsoft's crippling of GDI since Windows Vista by removing hardware acceleration of many operations) and there are endless issues with inconsistent double-buffering and DPI-scaling.
I suggest you rewrite your game's rendering layer in Unity, Direct2D or SDL.
I am currently working in Windows Form Apps and am making what will essentially be a map editor for a game. The way i have gone about this is by having a central TabControl where each TabPage contains a custom PictureBox control and all the other UI controls are around this central TabControl. The PictureBox uses its Paint event to draw everything that is placed on the map, and therefore draws multiple images of many sizes, rotations and scales etc to the single PictureBox. This has all gone well so far. The TabPage is essentially used as a view window for the PictureBox and is of size (1280x720).
The problem is with the scale to which the maps are being produced. The avg (and also maximum) map size on screen is around 19200x10800px and can be made up of hundreds of items at any one point. When drawing just a backdrop image of size 19200x10800px the PictureBox starts to flicker when it redraws and makes the program unusable. As the map is so big you are able to pan around them and this is where the flickering really shows. Also i do not want to use a 19200x10800px image source if possible for the sake of file sizes and the scaled image quality isn't an issue at all.
I have done heaps of reading on why this might be and feel like I have tried everything up until this point. So far ive tried:
Having the background image only 1920x1080 and scaling it up by 10x
Starting with a 1920x1080 image, programatically resizing it and drawing this image
Slicing the background into multiple segments (i tried many different amounts) and drawing only the ones that the view window can see (tried this for both a small(1080p) and large(10800p) images)
Using graphics clipping so that only the things on screen would be drawn
Used Double Buffering on both the picturebox and the form that the picturebox is on
Converting the image at initialisation to an "optimised bitmap" with faster formatting and then drawing the bitmap
I've probably tried a couple other things along with minor optimisations but its taken me so long ive forgotten the rest. From what i've read its most likely something to do with the control redrawing too slowly for some sort of performance reason or a limitation with picturebox's, however exactly what is going on i cannot tell due to lack of experience with form apps controls.
Currently to draw the background in the Paint event i have either:
g.DrawImage(image, new Rectangle(0, 0, (int)(image.Size.Width * levelScale), (int)(image.Size.Height * levelScale)));
or
g.ScaleTransform(levelScale, levelScale);
g.DrawImage(image, new Rectangle(0, 0, (int)(image.Size.Width), (int)(image.Size.Height)));
Where g is the Graphics object.
Have I hit the limit of Win form apps capabilities or is there something i may be missing?
Any and all help appreciated,
Thanks in advance.
Just for formality I though id answer my own question just in case anyone else would like to know the outcome.
Based off the overwhelming consensus that winforms was just not made to do the things I was trying to do with it I decided I had to move to some other platform. Suggested to me was WPF, DirectX and OpenGL but after some extensive searching around I found what I think is the optimal solution.
In order to utilise the power of DirectX hardware acceleration MS has made it so that you can embed XNA graphics devices into a winforms application. Essentially you can create custom controls that run in the normal winform style that have access to a much higher caliber of graphics control. In this manner (with a bit of extra work) I have replaced the picturebox I was using with a custom graphics control which handles all of the drawing. This has worked very well, and on the up side i havent had to take too much of a hit to my development time.
For those looking for more info refer to this question which has further links that should help. Once again thanks to all those who gave their advice!
This is a quoted answer from the URL at the bottom. There are code examples at the link at the bottom. Hope this is helpful; not sure if you tried this yet and maybe it'll help you get a little more juice out of the existing picturebox control. As explain in the other answers, it sounds like you will be forced to a more powerful solution in the near future regardless (DirectX/OpenGL or WPF)
** Partial quote from http://social.msdn.microsoft.com/Forums/en-US/68ecd1f6-2eeb-45ce-a881-24c62145ab0e/c-picturebox-problems
"I'd guess the real problem is that it takes too long to redraw the images. GDI+ is pretty slow, it doesn't use any video hardware acceleration. To speed it up, be sure to avoid rescaling the drawing and to use the Format32PArgb format. It is about 10 times faster than any other format. Load the images into a Bitmap with the right format first."
If you have a LOT of items (Maybe realized as controls), forget about the standard event mechanism of Windows Forms. Some time ago, i've written a logic gate editor/simulator which supported lots of thousands of gates in the editor and was really fast. There, I've used the canvas and draw the gates as custom "images" instead of putting them as controls. You'll have to write a custom GetUnderlyingGate function which resolves the current gate / tile (Is your editor a tilemap editor?) from a coordinate array. Also, there were some visible area optimizations.
Maybe, when i'm back home, I'll upload some sourcecode and notify you.
I have a C# application that has an existing WinForm that I now need to display upside down.
The application will be displayed on a touchscreen Windows 7 device. If two people are using the device, one person is viewing it right-side-up while another user will be simultaneously viewing it upside-down. I will need to have one control displayed right-side-up while another control is displayed upside-down, each duplicate forms. Both need to be functional. It is not necessary for the title bar and Windows close, maximize, and minimize to be rotated.
Is there a way to easily rotate this Form and all of its contents without having to rewrite it from scratch?
Unfortunately, rotating controls is not directly possible in WinForms.
At least, not if you want them to retain their functionality. It would be relatively simple to draw the control into a bitmap, rotate the bitmap, and then draw that back to the desired location on the form. But you would obviously lose the ability to interact with the controls. They would just be static representatives of their original selves.
But making functional upside-down controls just isn't going to happen. I mean, you could try to write a bunch of custom drawing code for owner-drawn controls, but you'll still run into a bunch of bugs, corner cases, and compatibility problems. The Win32 controls that WinForms is based on just don't support this. No big surprise, really, considering they were invented some 20–25 years before anyone thought of computer screens that you could carry around in your pocket and rotate in any direction. There is a good reason that UI technologies like WPF came out around the time that touch screens and tablets did.
There are some possibilities that can be explored when it comes to flipping the entire screen, but that's not going to help when you want different controls going different directions. (And I guess it betrays my vantage point as a desktop app guy when I say this, but that just sounds like an incredibly confusing UI.)
If you absolutely have to have this, someone else is going to have to give you another route to hack it, perhaps along the lines of Dhawalk's comment: hosting the WinForms control inside of a WPF app that does provide built-in support for rotated controls. I don't know enough about this to make any concrete suggestions down that path. From a few minutes of searching, it appears that WindowsFormsHost does not actually support rotation transforms, so this may be a non-starter anyway.
I'm using a timer to move a PictureBox inside a form. The picturebox leaves a white trail behind it which disappears when the picturebox stops. Is there any way to get rid of the white trail? I've tried this.Invalidate(); which removed the trail but caused the whole form to flimmer until the picturebox stopped.
If anyone could help me solve this problem I would be grateful!
It's generally much more difficult to do animations in WinForms than in WPF, because WinForms was not designed to support animations.
Have a look at the open source library Dot Net Transitions that provides some animation functionality to WinForms
The Transitions library lets you create animated transitions of any properties of user-interface elements for .NET. It provides an easy way to perform UI animations in .NET in a similar way to the Core Animation library for Apple and the iPhone.
http://code.google.com/p/dot-net-transitions/
this is my first ever question on this website but it has helped me a lot in the past.
i have a small (but annoying) problem with a project i am working on. i am using a picturebox control which loads a png file with transparent areas. the transparency part works perfectly fine, but i need the user to be able to drag this picturebox around with the mouse. the picturebox is contained within a panel with squares. the squares are drawn in an overridden OnPaint method of the panel.
the problem is that if i move the picturebox control, the area which is transparent does not draw the background fast enough and the squares are not drawn exactly where they should be. is there any way to get around this and make everything look nice and smooth?
i have attached a picture so that you can understand better what i am trying to say. for this example i am using just a line instead of the actual picture that i will be using so that everything is more obvious. notice the squares around the line, which are not in drawn properly.
http://s1084.photobucket.com/albums/j405/headbanging1638/?action=view¤t=problem.jpg
ps: i am using color.transparent for the backcolor of the picturebox
Maybe you could try to invalidate the layout on mousemove to force a faster rate of redraw?
I think pretty similar problem which I asked some time ago.
See my Question, and Answer which I accepted. I think it will help you.