DirectX to OpenGL matrix issue

Seems to me like you're not setting the viewport: https://www.khronos.org/opengles/sdk/docs/man/xhtml/glViewport.xml

In your Ubuntu screenshot, this is obvious, because the default viewport is (0, 0, 1, 1), so only the center of your cube shows through it.

In your Windows example, it's not clear what's happening - OpenGL probably takes the viewport size from the window's client area size, when you , but then you resize the window, and the old viewport no longer matches the new window size?

Check the examples in this thread for how to implement a resize callback and use it to set the viewport: http://www.gamedev.net/topic/661407-why-triangle-is-not-drawing/

Your implementation of Transpose() is absolutely unreasonable.
Unreasonably slow, and unreasonably complex and hard-to-follow. What did simplicity and efficiency do to make you hate them so?

	/**
	 * Swap two numbers.
	 *
	 * \param _fLeft The left operand.
	 * \param _fRight The right operand.
	 */
	template <typename _tType>
	NP_INLINE void NPAPI Swap( _tType &_fLeft, _tType &_fRight )
	{
		_tType fTemp = _fLeft;
		_fLeft = _fRight;
		_fRight = fTemp;
	}


	NP_INLINE void NPAPI Transpose()
	{
		Swap( m[0][1], m[1][0] );
		Swap( m[0][2], m[2][0] );
		Swap( m[0][3], m[3][0] );
		Swap( m[1][2], m[2][1] );
		Swap( m[1][3], m[3][1] );
		Swap( m[2][3], m[3][2] );
	}

The problem lies within m_displayWidth and m_displayHeight. It’s clear from the images that you are setting these values to the window (or…something?) width/height, not the client width/height.

You need to set these values to the actual client RECT of the window.

Show the code for creating the window and setting these values, and also any viewport code.

L. Spiro

The matrix transpose is based on the DirectXMath code. Thanks for your code :)

For the DX9/11 and OpenGL on windows, during the initialization of the render system, i adjust the window size

	// Setup the window size
	RECT windowRect;
	SetRect(&windowRect, 0, 0, m_displayWidth, m_displayHeight);
	if (m_windowedMode) {
		AdjustWindowRect(&windowRect, WS_OVERLAPPEDWINDOW, FALSE);
	}
	else {
		AdjustWindowRect(&windowRect, WS_POPUPWINDOW, FALSE);
	}
	
	// Resize the window
	if (m_windowedMode) {
		SetWindowLong(m_engine->GetWindow()->GetHWND(), GWL_STYLE, WS_OVERLAPPEDWINDOW);
		SetWindowPos(m_engine->GetWindow()->GetHWND(), HWND_TOP, 0, 0, windowRect.right - windowRect.left, windowRect.bottom - windowRect.top, SWP_FRAMECHANGED | SWP_NOMOVE | SWP_NOSIZE | SWP_SHOWWINDOW);
	}
	else {
		SetWindowLong(m_engine->GetWindow()->GetHWND(), GWL_STYLE, WS_POPUPWINDOW);	
		SetWindowPos(m_engine->GetWindow()->GetHWND(), HWND_TOP, 0, 0, windowRect.right - windowRect.left, windowRect.bottom - windowRect.top, SWP_FRAMECHANGED | SWP_NOMOVE | SWP_NOSIZE | SWP_SHOWWINDOW);
	}

As for linux, i don't adjust

	// Create the window
	m_window = XCreateWindow(m_display, RootWindow(m_display, m_visual->screen), 0, 0, 640, 480, 0, m_visual->depth, InputOutput, m_visual->visual, CWBorderPixel | CWColormap | CWEventMask | CWOverrideRedirect, &attributes);
	

(the display width/height settings are also set to 640x480 for this test)

D3D11 viewport:

	// Setup the viewport
	D3D11_VIEWPORT viewport;
	viewport.Width = (FLOAT)m_displayWidth;
	viewport.Height = (FLOAT)m_displayHeight;
	viewport.MinDepth = 0.0f;
	viewport.MaxDepth = 1.0f;
	viewport.TopLeftX = 0.0f;
	viewport.TopLeftY = 0.0f;

GL Viewport

glViewport(0, 0, m_displayWidth, m_displayHeight);

Ah, fixed the OpenGL windows issue.

There was an issue with the windows resizing (used SWP_NOSIZE)

After double checking everything, i see i changed my config to 800x600 while the window was created using 640x480 and the window was not resized correctly.

I will do some searching on the X11 window to see how i should resize :)

Thanks for the answers

There is clearly some kind of discrepancy here.

The reason Direct3D 11 is working is because the viewport and back back buffer are set to the same size, that size is not the same size as the window, and at some point it is being scaled to fit the screen. I would normally accuse IDirect3DDevice9::Present() or IDXGISwapChain::Present() but they do not do smooth scaling. Notice the anti-aliasing. Unless you have multi-sampling enabled, which you did not mention (but would internally be a different-sized buffer being scaled down).

You need to be looking for things related to this, not matrices. The problem is not related to the matrices or shaders.

L. Spiro

[EDIT]

Late post, after issue was solved.

[/EDIT]

There is no multi sampling or anything enabled, im using just very basic render settings.

The windows part is working now for DirectX and OpenGL, but as for linux, the issue remains the same :(

#elif defined(NP_PLATFORM_LINUX)
	// Resize the window
	XMoveResizeWindow(m_engine->GetWindow()->GetXDisplay(), m_engine->GetWindow()->GetXWindow(), 0, 0, m_displayWidth, m_displayHeight);

	// Create the context
	m_context = glXCreateContext(m_engine->GetWindow()->GetXDisplay(), m_engine->GetWindow()->GetXVisualInfo(), NULL, True);
	if (!m_context) {
		printf("Failed to create the GLX context\n");
	}

	// Make the current context
	if (!glXMakeCurrent(m_engine->GetWindow()->GetXDisplay(), m_engine->GetWindow()->GetXWindow(), m_context)) {
		printf("Failed to set the GLX context\n");
	}

	// Get the drawable
	m_drawable = glXGetCurrentDrawable();
#endif

	// Initialize the render API
	glewExperimental = GL_TRUE;
	glewInit();

	GLfloat viewportData[4];
	glGetFloatv(GL_VIEWPORT, viewportData);
	printf("viewport: %f; %f; %f; %f\n", viewportData[0], viewportData[1], viewportData[2], viewportData[3]);

	glViewport(0, 0, m_displayWidth, m_displayHeight);

Console output: viewport: 0.000000; 0.000000; 640.000000; 480.000000

m_displayWidth = 640

m_displayHeight = 480

const NpUInt32 NPAPI CLinuxWindow::InitializeClass()
{
	// Set the error handler
#if defined(NP_DEBUG)
	XSetErrorHandler(CLinuxWindow_XErrorHandler);
#endif

	// Get the default display and screen
	m_display = XOpenDisplay(0);
	m_screen = DefaultScreen(m_display);

	// Get the visual
	int visualNumber = 0;
	XVisualInfo visualTemplate;
	visualTemplate.screen = m_screen;
	visualTemplate.depth = 24;
	while (m_visual == NULL && (visualTemplate.depth >= 16)) {
		m_visual = XGetVisualInfo(m_display, VisualScreenMask | VisualDepthMask, &visualTemplate, &visualNumber);
		visualTemplate.depth -= 8;
	}
	printf("Choosen visual: %ld\n", m_visual->visualid);
 
	// Create the color map
	Colormap colormap = XCreateColormap(m_display, RootWindow(m_display, m_visual->screen), m_visual->visual, AllocNone);

	XSetWindowAttributes attributes;
	attributes.colormap = colormap;
	attributes.border_pixel = 0;
	attributes.event_mask = StructureNotifyMask | FocusChangeMask | ExposureMask;
	attributes.event_mask |= PointerMotionMask | ButtonPressMask | KeyPressMask | ButtonReleaseMask | KeyReleaseMask;
	attributes.override_redirect = false; //= m_fullscreen;

	// Create the window
	m_window = XCreateWindow(m_display, RootWindow(m_display, m_visual->screen), 0, 0, 640, 480, 0, m_visual->depth, InputOutput, m_visual->visual, CWBorderPixel | CWColormap | CWEventMask | CWOverrideRedirect, &attributes);
	
	// Show the window
	XMapRaised(m_display, m_window);

	// Add the destroy message
	Atom wmDelete;
	wmDelete = XInternAtom(m_display, CLinuxWindow_WM_DELETE_WINDOW, True);
	XSetWMProtocols(m_display, m_window, &wmDelete, 1);

	// Operation successful
	return NP_OK;
}

ps: The result for rendering 2D without matrices was the same for windows and linux

Err..

Don't use X11 directly. It's going to be replaced with other systems later on, where X11 will be running in emulation mode for a while until removed.

Use some library that abstracts all this away and does all the window handling for you on ALL operating systems.

For example SDL2.

Off topic from your actual problem, but there's one slight difference in D3D/GL matrices - D3D's final NDC z coords range from 0 to 1, and GL's from -1 to 1.
So without any changes, your game will end up wasting 50% of your depth buffer precision in the GL version. To fix this, you just need to modify the projection matrix to scale in z by 2 and offset by -1 so you're projecting into the full z range.

If you're using a GL-oriented math library, it will construct it's projection matrices like this by default, so you'd have to make the opposite scale/bias z adjustments to get D3D to work (the error would be a misbehaving near-clip plane, appearing too far out).

I made the SDL2 implementation for my render window on linux, but still having the same behavior, while the windows opengl result is now the same as DX

So i'm not sure whats missing (except for the Window/OpenGL context, all code is the same for windows/linux)

=== EDIT ===

Never mind ... got it working ;)

Seems the shaders in my working directory on Linux were not up to date. Guess my next step is working out a better FileManager before continue implementing OpenGL

Thanks for all the help for solving the issue