Overlaying a top-level window on top of another - c#

In the software products I'm currently working on, we have several 3D View controls. Appeared the need to have overlay information on top of these 3D Views. I won't go into too much background details, because it is not the point, but here are the constraints we face :
we must use two different 3D View controls
we don't have the source code for them
they are embedded in Windows Forms controls, and all our own GUIs around these controls are in Windows Forms
we use .NET Framework 3.5SP1 and Windows 7
We want to be able to display various overlay informations and controls on top of these 3D views, because we usually demo our products by showing full screen 3D views on big screens, and not show our GUIs, which have the necessary information and controls.
Back in the days we used only one type of 3D view, I managed, via various hacks involving reflection, to hook my own overlay window system written in DirectX (based on WorldWind .NET overlay widgets, the 3D view was indeed based on WorldWind at the time). The next version of the 3D View product made huge changes to the rendering core code and of course made these hacks incompatible (yeah, I had it coming, I know :-)). Moreover, we are now using, because of different needs in other products, another type of 3D View, closed source as well.
I emphasize the fact that we don't have the source code for them because we can't have access to the rendering loop and therefore cannot hook a windowing system made for 3D Engines, such as CEGUI (search for it yourself, I'm not allowed to post much hyperlinks yet, sorry).
Consequently, I had the following idea : since our 3D Views are embedded in winforms controls, why don't we code our overlay controls in plain winforms, and overlay it on top of the 3D views? The advantages of this solution are huge :
this would be compatible with both 3D Views, enabling us to reuse overlays across engines, if needed
we would be able to reuse custom controls or forms we already developed for the rest of the GUI. Indeed, it is a pretty big project, and we are beginning to have quite a library of such controls.
The only slight (!) problem is that we want to be able to manage overlay transluency, like I did with my former system in DirectX. We can't afford fully opaque overlays, because it would clutter the view too much. Imagine something like a barely visible overlay, becoming more opaque when the mouse is hovering over it for example.
Windows offer the possibility to have child windows inside other windows or controls (Win32 API doesn't really make a difference between windows and controls, this is pretty much a MFC/WinForms abstraction as I understood it), but since it is not top-level windows, we cannot adjust the transluency of these, so this is not something we can use. I saw here, that this is however possible on Windows 8, but switching to windows 8 is not possible anytime soon, because our software is deployed on quite a few machines, running 7.
So I started an intense googling session on how could I work around such a problem. It appears I must "enslave" top level windows to my 3D View controls. I already tried out something like that directly in winforms, having a form owned (not parented, there is a clear distinction, read about it in the previously linked MS page) by a control, and "following" its movements on screen. As expected, it kind of worked, but the issues are difficult to overcome. The most important is a clipping issue. If the parent form of the owner control changes its size, the overlay form is still shown in full. In my sample, I have a simple form with a menu, and a black panel containing a calendar (to show clipping differences between child controls and owned ones). I "enslaved" a borderless form containing a property grid to the black panel. It successfully follows the forms movements, but if I shrink the main form, I get this :
Clipping issue screenshot
Note how the calendar is clipped correctly (child window), and the overlay is not (owned window). I also get weird effects when minimizing/restoring the main form. Indeed, my overlay disappears when minimizing, but when restoring, it just "spawns" while the restoring animation of the main form is occuring. But this is less of an issue, and I guess can be worked around by handling proper events (but which ones?).
From what I understood, I must handle at least some of the clipping myself, using win32 API calls and hooks. I already begun to document myself, but it is quite complicated stuff. The Win32 API being a real mess, and myself being a former Unix developer introduced to Windows programming via the great .NET framework, I don't have any real experience in Win32, and therefore don't really know where to begin, and how to make myself a path in this jungle...
So if a winapi guru is passing by, or if someone has some other idea to achieve my goals given the constraints above, I'll be glad to read about it :-)
Thanks in advance, and apologies for being such a stackoverflow "leecher" by subscribing only to ask a question, but I don't have no direct internet access on my workstation (yeah, for real, I have to go to a specific computer for this), so participating in this great community is not that easy for me.
Finally, here is my sample code (designer code available if you ask) :
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
Point _myLoc;
private void formToolStripMenuItem_Click(object sender, EventArgs e)
{
var ctrl = new PropertyGrid();
var obj = this.panel1;
ctrl.SelectedObject = obj;
var form = new Form();
ctrl.Dock = DockStyle.Fill;
form.Controls.Add(ctrl);
form.Opacity = 0.7;
var rect = obj.RectangleToScreen(obj.DisplayRectangle);
form.StartPosition = FormStartPosition.Manual;
form.Location = new Point(rect.Left + 10, rect.Top + 10);
var parentForm = this;
_myLoc = parentForm.Location;
form.FormBorderStyle = FormBorderStyle.None;
parentForm.LocationChanged += (s, ee) => {
int deltaX = parentForm.Location.X - _myLoc.X;
int deltaY = parentForm.Location.Y - _myLoc.Y;
var loc = form.Location;
form.Location = new Point(loc.X + deltaX, loc.Y + deltaY);
_myLoc = parentForm.Location;
};
form.Show(this.panel1);
}
}

Clipping can be easily implemented using Region property. Each window can have an associated Region object, which defines window rendering constraints:
static void ManualClipping(Control clipRegionSource, Form formToClip)
{
var rect = clipRegionSource.DisplayRectangle;
rect = clipRegionSource.RectangleToScreen(rect);
rect = formToClip.RectangleToClient(rect);
rect = Rectangle.Intersect(rect, formToClip.ClientRectangle);
if(rect == formToClip.ClientRectangle)
{
formToClip.Region = null;
}
else
{
formToClip.Region = new Region(rect);
}
}
usage:
/* ... */
parentForm.SizeChanged += (s, ee) => ManualClipping(panel1, form);
form.Show(this.panel1);

Related

How to properly resize app to visible bounds on UWP? (VisibleBoundsMode doesn't seem to work)

I have two UWP apps and after testing them out with Continuum I noticed the app bar of the OS (the bar with the Start button) at the bottom of the screen (it can be at each of the 4 edges of the screen, of course) was covering part of my app.
Now, I'm already using ApplicationView.GetForCurrentView().SetDesiredBoundsMode(ApplicationViewBoundsMode.UseVisible) before calling Window.Current.Activate(), but that doesn't seem to solve the issue.
1) Why is it that setting the DesiredBoundsMode property doesn't seem to work here? Shouldn't that automatically resize the window
content to the visible bounds (ie. excluding system overlays like the
navigation bar or the app bar)?
The workaround I'm using for now on Windows 10 Mobile devices is to subscribe to the VisibleBoundsChanged event and then manually adjust the margins of my Window.Current.Content item to make sure it doesn't show anything behind covered areas of the screen.
Basically, I use the Window.Current.Bounds property and the ApplicationView.VisibleBounds property to calculate the occluded areas on the different edges of the app window, and increase the margins from there.
2) Is there a proper/better way to do this?
I mean, I'm quite sure there's another method that should be used to avoid this issue (considering there are tons of different situations like Continuum, navigation bar etc... that I don't think are supposed to be manually handled one by one).
Thank you for your help!
Use the subscription to the event VisibleBoundsChanged. This is the best solution that I found.
var curr = ApplicationView.GetForCurrentView();
if (curr.IsFullScreenMode == true)
{
ApplicationView.PreferredLaunchWindowingMode = ApplicationViewWindowingMode.FullScreen;
curr.FullScreenSystemOverlayMode = FullScreenSystemOverlayMode.Minimal;
}
else
{
ApplicationView.PreferredLaunchWindowingMode = ApplicationViewWindowingMode.Auto;
curr.FullScreenSystemOverlayMode = FullScreenSystemOverlayMode.Standard;
}

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.

c# control location precision

I need more precision then integer based locations when puttng controls on a form.
It seems control.location only supports Point.
Is there a work around for this?
Point p = new Point(100, 200);
this.Location = p;// this works of course
PointF pF = new PointF(100.04f, 200.08f);
this.Location = pF;// this does not work of course because Location expects a Point not PointF
Is there some setting on the base form, or base control I can set to have more location precision?
You could use Windows Presentation Foundation (WPF) together with XAML (both work nicely within Visual Studio), which allows subpixel positioning of controls.
However, assuming that you are using Windows Forms and not WPF, why would you ever need to put a control on a non-integer (subpixel) location?
Although GDI+ is capable of floating point coordinate systems, Win32 (upon which Winforms is based) is not. I second the reccomendation to move to WPF which has a ubiquitous floating point coordinate system based on device independent virtual pixels.
No, control rendering in WinForms is all fundamentally pixel-based. There is a way you could achieve sub-pixel positioning (without using WPF), but it would be work on your part, and I'm really not sure why you would need this anyway.
The gist of the approach is to create a user control with a hidden instance of the control you're trying place funkily (sub-pixelly, maybe). You wire up all the user control's events so that they pass through to the hidden control, and after each event is passed you call the hidden control's DrawToBitmap method to get a snapshot of the control. You then use Graphics.DrawImage to copy the snapshot to the surface of the user control. DrawImage is not restricted to pixels, so you can offset the drawing by less than a pixel to achieve the precise positioning you're looking for.
Warning: please do not actually do this, as there is no reason for it when you can just use WPF. This would be a lot of work, since "passing the control's events through" is not as simple matter as it sounds. There's also a problem with rendering the focus correctly in this manner, as the invisible control cannot be given the focus (I'm not even going to tell you what the grisly hack solution is to that problem).
Update: It's worth revisiting that decision about WPF - it is ideal for what you're doing and would make your life much simpler. I have been generally underwhelmed by WPF, because I think that while it's very powerful it is essentially overpowered for the uses to which it is most often put (namely, boring-ass business apps). In your case, though, it provides a granularity that you actually require in your app.
If you're stuck in WinForms, however, your best approach is to write your own UserControl versions of the text-editing controls that your application requires. At its core, a TextBox is just a square that you draw a border around and some text on. The .Net Graphics methods for this (DrawRectangle and DrawString) can have the drawing coordinates specified in floating point.
There are tons of StackOverflow questions about owner-drawn user controls and GDI+ graphics.
1 point is 1 pixel and therefore the maximum resolution required.
This is the reason why 0,0 maps to the left corner, and 1024 maps to the right, in a resolution of 1024x768

[C#][XNA 3.1] How can I host two different XNA windows inside one Windows Form?

I am making a Map Editor for a 2D tile-based game. I would like to host two XNA controls inside the Windows Form - the first to render the map; the second to render the tileset. I used the code here to make the XNA control host inside the Windows Form. This all works very well - as long as there is only one XNA control inside the Windows Form. But I need two - one for the map; the second for the tileset. How can I run two XNA controls inside the Windows Form? While googling, I came across the terms "swap chain" and "multiple viewports", but I can't understand them and would appreciate support.
Just as a side note, I know the XNA control example was designed so that even if you ran 100 XNA controls, they would all share the same GraphicsDevice - essentially, all 100 XNA controls would share the same screen. I tried modifying the code to instantiate a new GraphicsDevice for each XNA control, but the rest of the code doesn't work. The code is a bit long to post, so I won't post it unless someone needs it to be able to help me.
Thanks in advance.
I have done something similar to what you are trying to do. All you need to do is tell the graphics device where to present the "stuff" you have rendered. You do this by passing it a pointer to a canvas.
Here is a sample form class:
public class DisplayForm : Form
{
IntPtr canvas;
Panel displaypanel;
public Panel DisplayPanel
{
get { return displaypanel; }
set { displaypanel = value; }
}
public IntPtr Canvas
{
get { return canvas; }
set { canvas = value; }
}
public DisplayForm()
{
displaypanel = new Panel();
displaypanel.Dock = DockStyle.Fill;
this.canvas = displaypanel.Handle;
this.Controls.Add(displaypanel);
}
}
Then simply add this to your game class draw call:
graphics.GraphicsDevice.Present(displayform.Canvas);
After you are done drawing to that instance of DisplayForm you can clear, render something else, and call Present again pointing to another canvas.
You might find these two XNA samples useful:
http://creators.xna.com/en-US/sample/winforms_series1
http://creators.xna.com/en-US/sample/winforms_series2
Just a thought but have you considered making this app of yours an MDI app?
that way you can load a form that contains 1 instance of xna multiple times.
Failing that ... do what RodYan suggests :)

MDX/SlimDX messes up WPF scrollbars?

I have a very simple WPF user control that is mixed in with a windows forms app. It has a list box that renders its scroll bar without the thumb (image below). I narrowed it down to a plugin in my app that uses Managed DirectX (MDX). If I remove the plugin, the scroll bar is just fine. I know MDX is deprecated, but I don't think today is the day to consider an upgrade. Has anyone ever seen their scroll bar get messed up, or has any idea what I should do?
And I should add, that this control also lives in a plugin. There is no way for the 2 plugins to reference each other.
<UserControl x:Class="MAAD.Plugins.Experiment.Visual.TestEditor"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Height="403" Width="377">
<ListBox Margin="12" Name="listBox1" />
</UserControl>
Update: You can read about the solution below.
As it turns out, I stumbled on the solution today while working with a client. If you add the CreateFlags.FpuPreserve flag to your device creation, the scrollbar should go back to normal.
I've seen this bug too. It is not a SlimDX issue per se, but rather due to DirectX using 32-bit math on the x87 FP stack.
Use the FpuPreserve flag when initializing your device and the problem should go away.
My suggestion is to get rid of your MDX plugin.
I've used both WPF and MDX, though not in the same project. Both libraries talk to DirectX and ultimately will store state at the native level, which can cause problems. With WPF I've had rendering issues related to my video drivers and the fix was to upgrade the video driver to a newer version.
Initializing DirectX can affect the ways DirectX (and your CPU!) performs for your whole application . For example, when you initialize MDX by default it will set the CPU to do all floating point calculations in single precision, for the whole process, regardless of how you declare your original value. As you might imagine this lead to a lot of head scratching for a long time as to why we were getting different results in the application and our unit tests.
I suspect that when MDX is initializing it is enabling, or disabling some feature or setting in your graphics card (or possibly some software setting) that is affecting the WPF pipeline somehow.
I wish I could be more helpful. Good Luck.
I had this problem as well. As mpg found, adding the D3DCREATE_FPU_PRESERVE flag to the device creation will fix it. if anyone is wondering what the code looks like:
d3d->CreateDevice(
D3DADAPTER_DEFAULT,
D3DDEVTYPE_HAL,
(HWND)this->Handle.ToPointer(),
D3DCREATE_HARDWARE_VERTEXPROCESSING|D3DCREATE_FPU_PRESERVE,
&d3dpp,
p);
Have you tried SlimDX instead of MDX? SlimDX is a newer wrapper around DX and is actively under development. Perhaps you could do in SlimDX the same thing you use your MDX-Plugin for and the scrollbar functions normally again.
Peter is right about the interaction of WPF and MDX. WPF uses DirectX internally. So changing settings in MDX (or SlimDX) can change how WPF behaves. You could also try to take a look at the code of the WPF scrollbar (for example with the .NET Reflector, IDA, whatever you need) and check the settings the Scrollbar relies on.
Are you on Vista? We've seen a lot of SlimDX/WPF simply vanish by creating a Direct3D9Ex device instead of a normal one when running under Vista targets.
I took everyone's advice and ported my app to SlimDX. It wasn't too bad (almost every class/method/field is named exactly the same in SlimDX as MDX). Unfortunately, I still had the same issue. I was able to simplify Both SlimDX and MDX down to the following app:
public partial class MainForm : Form
{
Direct3D Direct3D = new Direct3D();
Panel slimPanel = new Panel();
public MainForm()
{
InitializeComponent();
CreateDevice();
BuildWindows();
}
void BuildWindows()
{
var listBox = new System.Windows.Controls.ListBox();
listBox.ItemsSource = Enumerable.Range(0, 100);
var elementHost = new ElementHost();
elementHost.Child = listBox;
elementHost.Dock = DockStyle.Fill;
Controls.Add(elementHost);
slimPanel.Dock = DockStyle.Left;
Controls.Add(slimPanel);
}
void CreateDevice()
{
PresentParameters presentParams = new PresentParameters();
presentParams.BackBufferHeight = slimPanel.ClientRectangle.Height;
presentParams.BackBufferWidth = slimPanel.ClientRectangle.Width;
presentParams.DeviceWindowHandle = slimPanel.Handle;
var device = new Device(Direct3D, 0, DeviceType.Hardware, slimPanel.Handle, CreateFlags.HardwareVertexProcessing, presentParams);
}
}
The scroll bar won't show. I was able to get the scrollbar to show if I made sure the listbox got to paint before the Device was created.
The final solution was to add a WPF ListBox to my form in the constructor then delete it after the form finishes loading. I'm not sure if this is a bug in WPF or DirectX, I might try submitting a bug with Microsoft.
BTW, I can't get XNA to cause this issue.
I'd second the reservations of the previous posters regarding MDX in the context of WPF. One shot into the dark though:
Have you tried targeting your control for .NET Framework 3.5 SP1 already? There has been significant work regarding DirectX/Direct3D interoperability and performance, see for example:
Paragraph 'Graphics Enhancements' in What's New in .NET Framework 3.5 Service Pack 1
Paragraph 'WPF Interoperability with Direct3D' in What's New in .NET Framework 3.5 Service Pack 1
Some of those enhancements might eventually yield positive side effects regarding your problem.

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