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Custom TabControl display issues

I've been writing a custom drawn tab control for a few days now and for the most part everything is pretty and it does an amazing job ... except when I use it on my Windows 10 computer (at run-time).
I've gone back to the most basic few lines of code to trace the error and I can't for the life of me figure this out.
Below is the only code being used, in a nutshell I'm designing a horizontal aligned tab control.
using System.Drawing;
using System.Windows.Forms;
namespace WindowsFormsApplication1.UI
{
class TabControlTest : TabControl
{
public TabControlTest()
{
Alignment = TabAlignment.Left;
SizeMode = TabSizeMode.Fixed;
}
}
}
I've simply added the custom tab control to the form, added a couple of group boxes for reference purposes and changed the background colour of the form to grey so you can clearly see the tab control.
Now, at design time the 2 group boxes (1 in the tab control, 1 on the form) align perfectly.
But at run-time I see a very different result.
As you can see the tab part of the control is now larger than it was at design time and the resulting change means the contexts of the tab have also moved.
If I do this on a Windows 7 computer everything is displayed as it appears at design time, as it should!
I've added ImageSize but it makes no difference.
ItemSize = new System.Drawing.Size(30, 150);
I've reinstalled VS on my (Win10) development machine. I'm at a loss to explain why and how to resolve this.
Any/all help would be immensely appreciated.

Looking at your tab width in your comparison images, I believe this is another issue caused by automatic Windows control scaling. I found that it is the dpiAware option is automatically set when it's run from within Visual Studio and then reverts back to the default Windows Scaling that windows Implements when outside Visual Studio.
To prevent that auto-scaling when run outside Visual Studio altogether you need to Notify the OS that you're application is dpiAware by calling the Win32 P/Invoke SetProcessDPIAware() method from within your Main() before Application.Run() is called, like the example below demonstrates. This will let your controls use the native resolution which your designing the coordinates from.
static class Program
{
[System.Runtime.InteropServices.DllImport("user32.dll")]
private static extern bool SetProcessDPIAware();
static void Main(string[] args)
{
if (Environment.OSVersion.Version.Major >= 6)
SetProcessDPIAware();
Application.Run(new UIMonitor());
}
}
Alternatively, if you want to keep the scaling, you may be able to set the GroupBox location based off the Width of the Tab Control instead of a specific location. (Or by using some combination of Control measurements instead of exact picel placement.)

Moving a picturebox without redrawing it? [duplicate]

I need to knock out a quick animation in C#/Windows Forms for a Halloween display. Just some 2D shapes moving about on a solid background. Since this is just a quick one-off project I really don't want to install and learn an entire new set of tools for this. (DirectX dev kits, Silverlight, Flash, etc..) I also have to install this on multiple computers so anything beyond the basic .Net framework (2.0) would be a pain in the arse.
For tools I've got VS2k8, 25 years of development experience, a wheelbarrow, holocaust cloak, and about 2 days to knock this out. I haven't done animation since using assembler on my Atari 130XE (hooray for page flipping and player/missile graphics!)
Advice? Here's some of the things I'd like to know:
I can draw on any empty widget (like a panel) by fiddling with it's OnPaint handler, right? That's how I'd draw a custom widget. Is there a better technique than this?
Is there a page-flipping technique for this kind of thing in Windows Forms? I'm not looking for a high frame rate, just as little flicker/drawing as necessary.
Thanks.
Post Mortem Edit ... "a couple of coding days later"
Well, the project is done. The links below came in handy although a couple of them were 404. (I wish SO would allow more than one reply to be marked "correct"). The biggest problem I had to overcome was flickering, and a persistent bug when I tried to draw on the form directly.
Using the OnPaint event for the Form: bad idea. I never got that to work; lots of mysterious errors (stack overflows, or ArgumentNullExceptions). I wound up using a panel sized to fill the form and that worked fine.
Using the OnPaint method is slow anyway. Somewhere online I read that building the PaintEventArgs was slow, and they weren't kidding. Lots of flickering went away when I abandoned this. Skip the OnPaint/Invalidate() and just paint it yourself.
Setting all of the "double buffering" options on the form still left some flicker that had to be fixed. (And I found conflicting docs that said "set them on the control" and "set them on the form". Well controls don't have a .SetStyle() method.) I haven't tested without them, so they might be doing something (this is the form):
this.SetStyle(ControlStyles.UserPaint, true);
this.SetStyle(ControlStyles.OptimizedDoubleBuffer, true);
this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);
So the workhorse of the code wound up looking like (pf is the panel control):
void PaintPlayField()
{
Bitmap bufl = new Bitmap(pf.Width, pf.Height);
using (Graphics g = Graphics.FromImage(bufl))
{
g.FillRectangle(Brushes.Black, new Rectangle(0, 0, pf.Width, pf.Height));
DrawItems(g);
DrawMoreItems(g);
pf.CreateGraphics().DrawImageUnscaled(bufl, 0, 0);
}
}
And I just called PaintPlayField from the inside of my Timer loop. No flicker at all.

Set off a timer at your desired frame rate. At each timer firing twiddle the internal representation of the shapes on the screen (your model) per the animation motion you want to achieve, then call Invalidate(true). Inside the OnPaint just draw the model on the screen.
Oh yeah, and you probably want to turn Double Buffering on (this is like automatic page flipping).

2d Game Primer
Timer Based Animation
Both of these give good examples of animation. The code is fairly straightforward. i used these when I needed to do a quick animation for my son.

Panel is flickering when switching from one winform to another

I render my image on the panel.
using Microsoft.DirectX.Direct3D;
Device device;
this.device = new Device(0, DeviceType.Hardware, this.panel2,
CreateFlags.HardwareVertexProcessing, presentationParameters);
As a result, the panel is flickering when I try to switch the winform from one to another.
I know it is hard to describe the scenario. Hence I hereby upload a video clip (.swf) to my google drive, you guys may download it and open it with window media player to watch the video.
Below is the shared link:
https://drive.google.com/file/d/0B6wTfkJvzke_aVJwanVkaU1iSVU/edit?usp=sharing
Inside the video, I am running my application at debug mode, then I click on the 'chrome browser' tab in task bar to access the 'chrome browser', when the minimized 'chrome browser' pop out, the panel will be flickered. Then when I minimize the 'chrome browser' again, the panel flickered again.
The problem occur when there is some other winform being placed above the panel on screen.
Any comment on the above matter? Help is needed.

I ran into the same flicker issues when using DirectX with Panel. It turned out that the OS draw events were colliding my own. To fix this, you need to disable OS drawing on your Panel by creating a custom panel. Something as simple as this should suffice.
class Direct3DPanel : Panel
{
public Direct3DPanel()
{
this.SetStyle(ControlStyles.UserPaint | ControlStyles.AllPaintingInWmPaint | ControlStyles.Opaque, true);
}
}
The SetStyle method call tells the OS that only you should draw in Direct3DPanel. Note that once you do this, you will be responsible for all drawing. You may need to handle the Paint event and call your draw logic depending on your current architecture.
You can get more information about the different ControlStyles here
http://msdn.microsoft.com/en-us/library/system.windows.forms.controlstyles(v=vs.110).aspx

Translate and rotate image outside of glControl1_Paint using OpenTK?

I am making CAD type software in VS2010 Pro using a C# Windows Form Application and OpenTK. Nothing fancy; I just want to be able to read in some basic shapes and draw them. I'm not sure if this makes a difference to the answer, but I am drawing in 2D space using GL.Ortho();
To get familiar with graphics I've done a few OpenTK examples straight from the OpenTK documentation and have a basic understanding of it. From what I've learned so far I cannot move/rotate my primitives unless they were created within this event:
private void glControl1_Paint(object sender, PaintEventArgs e)
{
}
My program launches and waits for the user to select the CAD file to read in. After I read the file and break it down into primitives I draw it to the glControl1 form. So far it works as expected. However, I do not draw it in the "glControl1_Paint" event. Thus I have no control to translate/rotate it by using keyboard/mouse inputs.
I have read answers to other questions where the asker was directed to draw in the "glControl1_Paint" event. I would love to because it would solve my problem, but I am not sure how to do that since I don't have the primitives upon launch of the application, I wait for the user to provide the data.
I suppose I have a few questions that I would like to know the answers to:
1) When does the "glControl1_Paint" event happen in the program? I assumed it was part of initializing the glControl1 window and fired upon startup. Can I control when this happens so that I can draw my primitives here? If so, how do I control when this happens and how do I pass my geometry into this?
2) Is there a way to translate/rotate the my primitives outside of the "glControl1_Paint" event?

No you can not know when paint event will trigger. But you can manually trigger it via Invalidate() function.
The flow should be like this.
You should do the all the drawing in your paint event.
If something happened that effects the drawing, you should call Invalidate()
Keyboard events that moves objects or mouse events that rotates camera etc. all of them should call Invalidate()
If you like maximum frame rate. you should override application main loop and make it call Invalidate() if there are no other windows messages to process.
here is my programming loop
static void Main()
{
...
MainForm mainFrom = new MainForm();
mainFrom.FormClosed += QuitLoop;
mainFrom.Show();
do
{
Application.DoEvents();
mainFrom.glControl1.Invalidate(true); //actually may program is a lot more complex than this
if (mainFrom.IsRunning)
System.Threading.Thread.Sleep(0);
else
System.Threading.Thread.Sleep(1);
} while (!mQuit);
...

How to make label & other controls transparent with background image on windows mobile?

I am developing the smart device application in C#. I am new to the windows mobile. I have added the background image to the form in my application by using the following code. I want to make label & other controls on this form transparent so that my windows form will be displayed properly.
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
Bitmap CreateCustomerImage = new Bitmap(#"/Storage Card/background.png");
e.Graphics.DrawImage(CreateCustomerImage, 0, 0);
}
how to do this ? How to solve this problem? Can you provide me any code or link through which I can solve the above issue?

Windows CE doesn't inherently support transparent controls, which tends to be a huge pain. You have to use something like ColorKey transparency, so in your OnPaint, you need to fill the background with a color (magenta is a popular one) and use SetColorKey to make that color transparent.
There are several tutorials online for colorkey transparency. Here is one that I just found with a search engine that looks reasonable but feel free to search for others as well.
The place this falls down is when you have controls in a container control, which is then on the Form. To get that to work right you have to cascade calls to clipping regions from the Form all the way down. I don't have a ready sample of this that isn't inside a shipping project, so I can't easily post it. If you run into this, though, update the question and I'll see if I can extract something.