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    • By Ty Typhoon
      Before read everything i am honest:
      Payment after release you get your percentage lifetime for that project.
       
      Second:
      i dont need your inspirations, ideas, music or designs.
      My head is full with that.
      I need workers who i can trust.
       
       
       
      Please let us talk in discord.
      I got a lot of stuff planned, there is much work to do.
       
      But first my team and me try to start with a small mini game and we need maybe exactly you.
      Planned for more than pc, like ps4, xbox one and mobile - so its very important to us to hopefully welcome a programmer.
       
      The mini game will be part of the planned big game. There will be never before seen guns and gameplay, you will get deeper info if youre a safe part of the team.
       
      I need:
      Programmers
      Animators
      Zbrush pros
       
      Join here please:
      https://discord.gg/YtjE3sV
       
      You find me here:
      Joerg Federmann Composing#2898
       
       
    • By tj8146
      I am using immediate mode for OpenGL and I am creating a 2D top down car game. I am trying to configure my game loop in order to get my car-like physics working on a square shape. I have working code but it is not doing as I want it to. I am not sure as to whether it is my game loop that is incorrect or my code for the square is incorrect, or maybe both! Could someone help because I have been trying to work this out for over a day now
      I have attached my .cpp file if you wish to run it for yourself.. 
      WinMain code:
      /******************* WIN32 FUNCTIONS ***************************/ int WINAPI WinMain( HINSTANCE hInstance, // Instance HINSTANCE hPrevInstance, // Previous Instance LPSTR lpCmdLine, // Command Line Parameters int nCmdShow) // Window Show State { MSG msg; // Windows Message Structure bool done=false; // Bool Variable To Exit Loop Car car; car.x = 220; car.y = 140; car.dx = 0; car.dy = 0; car.ang = 0; AllocConsole(); FILE *stream; freopen_s(&stream, "CONOUT$", "w", stdout); // Create Our OpenGL Window if (!CreateGLWindow("OpenGL Win32 Example",screenWidth,screenHeight)) { return 0; // Quit If Window Was Not Created } while(!done) // Loop That Runs While done=FALSE { if (PeekMessage(&msg,NULL,0,0,PM_REMOVE)) // Is There A Message Waiting? { if (msg.message==WM_QUIT) // Have We Received A Quit Message? { done=true; // If So done=TRUE break; } else // If Not, Deal With Window Messages { TranslateMessage(&msg); // Translate The Message DispatchMessage(&msg); // Dispatch The Message } } else // If There Are No Messages { if(keys[VK_ESCAPE]) done = true; void processKeys(Car& car); //process keyboard while (game_is_running) { loops = 0; while (GetTickCount() > next_game_tick && loops < MAX_FRAMESKIP) { update(car); // update variables next_game_tick += SKIP_TICKS; loops++; } display(car); // Draw The Scene SwapBuffers(hDC); // Swap Buffers (Double Buffering) } } } // Shutdown KillGLWindow(); // Kill The Window return (int)(msg.wParam); // Exit The Program } //WIN32 Processes function - useful for responding to user inputs or other events. LRESULT CALLBACK WndProc( HWND hWnd, // Handle For This Window UINT uMsg, // Message For This Window WPARAM wParam, // Additional Message Information LPARAM lParam) // Additional Message Information { switch (uMsg) // Check For Windows Messages { case WM_CLOSE: // Did We Receive A Close Message? { PostQuitMessage(0); // Send A Quit Message return 0; // Jump Back } break; case WM_SIZE: // Resize The OpenGL Window { reshape(LOWORD(lParam),HIWORD(lParam)); // LoWord=Width, HiWord=Height return 0; // Jump Back } break; case WM_LBUTTONDOWN: { mouse_x = LOWORD(lParam); mouse_y = screenHeight - HIWORD(lParam); LeftPressed = true; } break; case WM_LBUTTONUP: { LeftPressed = false; } break; case WM_MOUSEMOVE: { mouse_x = LOWORD(lParam); mouse_y = screenHeight - HIWORD(lParam); } break; case WM_KEYDOWN: // Is A Key Being Held Down? { keys[wParam] = true; // If So, Mark It As TRUE return 0; // Jump Back } break; case WM_KEYUP: // Has A Key Been Released? { keys[wParam] = false; // If So, Mark It As FALSE return 0; // Jump Back } break; } // Pass All Unhandled Messages To DefWindowProc return DefWindowProc(hWnd,uMsg,wParam,lParam); }  
      C++ and OpenGL code:
      int mouse_x=0, mouse_y=0; bool LeftPressed = false; int screenWidth=1080, screenHeight=960; bool keys[256]; float radiansFromDegrees(float deg) { return deg * (M_PI / 180.0f); } float degreesFromRadians(float rad) { return rad / (M_PI / 180.0f); } bool game_is_running = true; const int TICKS_PER_SECOND = 50; const int SKIP_TICKS = 1000 / TICKS_PER_SECOND; const int MAX_FRAMESKIP = 10; DWORD next_game_tick = GetTickCount(); int loops; typedef struct { float x, y; float dx, dy; float ang; }Car; //OPENGL FUNCTION PROTOTYPES void display(const Car& car); //called in winmain to draw everything to the screen void reshape(int width, int height); //called when the window is resized void init(); //called in winmain when the program starts. void processKeys(Car& car); //called in winmain to process keyboard input void update(Car& car); //called in winmain to update variables /************* START OF OPENGL FUNCTIONS ****************/ void display(const Car& car) { const float w = 50.0f; const float h = 50.0f; glClear(GL_COLOR_BUFFER_BIT); glLoadIdentity(); glTranslatef(100, 100, 0); glBegin(GL_POLYGON); glVertex2f(car.x, car.y); glVertex2f(car.x + w, car.y); glVertex2f(car.x + w, car.y + h); glVertex2f(car.x, car.y + h); glEnd(); glFlush(); } void reshape(int width, int height) // Resize the OpenGL window { screenWidth = width; screenHeight = height; // to ensure the mouse coordinates match // we will use these values to set the coordinate system glViewport(0, 0, width, height); // Reset the current viewport glMatrixMode(GL_PROJECTION); // select the projection matrix stack glLoadIdentity(); // reset the top of the projection matrix to an identity matrix gluOrtho2D(0, screenWidth, 0, screenHeight); // set the coordinate system for the window glMatrixMode(GL_MODELVIEW); // Select the modelview matrix stack glLoadIdentity(); // Reset the top of the modelview matrix to an identity matrix } void init() { glClearColor(1.0, 1.0, 0.0, 0.0); //sets the clear colour to yellow //glClear(GL_COLOR_BUFFER_BIT) in the display function //will clear the buffer to this colour. } void processKeys(Car& car) { if (keys[VK_UP]) { float cdx = sinf(radiansFromDegrees(car.ang)); float cdy = -cosf(radiansFromDegrees(car.ang)); car.dx += cdx; car.dy += cdy; } if (keys[VK_DOWN]) { float cdx = sinf(radiansFromDegrees(car.ang)); float cdy = -cosf(radiansFromDegrees(car.ang)); car.dx += -cdx; car.dy += -cdy; } if (keys[VK_LEFT]) { car.ang -= 2; } if (keys[VK_RIGHT]) { car.ang += 2; } } void update(Car& car) { car.x += car.dx*next_game_tick; }  
      game.cpp
    • By tj8146
      I am using immediate mode for OpenGL and I am creating a 2D top down car game. I am trying to configure my game loop in order to get my car-like physics working on a square shape. I have working code but it is not doing as I want it to. I am not sure as to whether it is my game loop that is incorrect or my code for the square is incorrect, or maybe both! Could someone help because I have been trying to work this out for over a day now
      I have attached my .cpp file if you wish to run it for yourself.. 
       
      This is my C++ and OpenGL code:
      int mouse_x=0, mouse_y=0; bool LeftPressed = false; int screenWidth=1080, screenHeight=960; bool keys[256]; float radiansFromDegrees(float deg) { return deg * (M_PI / 180.0f); } float degreesFromRadians(float rad) { return rad / (M_PI / 180.0f); } bool game_is_running = true; const int TICKS_PER_SECOND = 50; const int SKIP_TICKS = 1000 / TICKS_PER_SECOND; const int MAX_FRAMESKIP = 10; DWORD next_game_tick = GetTickCount(); int loops; typedef struct { float x, y; float dx, dy; float ang; }Car; //OPENGL FUNCTION PROTOTYPES void display(const Car& car); //called in winmain to draw everything to the screen void reshape(int width, int height); //called when the window is resized void init(); //called in winmain when the program starts. void processKeys(Car& car); //called in winmain to process keyboard input void update(Car& car); //called in winmain to update variables /************* START OF OPENGL FUNCTIONS ****************/ void display(const Car& car) { const float w = 50.0f; const float h = 50.0f; glClear(GL_COLOR_BUFFER_BIT); glLoadIdentity(); glTranslatef(100, 100, 0); glBegin(GL_POLYGON); glVertex2f(car.x, car.y); glVertex2f(car.x + w, car.y); glVertex2f(car.x + w, car.y + h); glVertex2f(car.x, car.y + h); glEnd(); glFlush(); } void reshape(int width, int height) // Resize the OpenGL window { screenWidth = width; screenHeight = height; // to ensure the mouse coordinates match // we will use these values to set the coordinate system glViewport(0, 0, width, height); // Reset the current viewport glMatrixMode(GL_PROJECTION); // select the projection matrix stack glLoadIdentity(); // reset the top of the projection matrix to an identity matrix gluOrtho2D(0, screenWidth, 0, screenHeight); // set the coordinate system for the window glMatrixMode(GL_MODELVIEW); // Select the modelview matrix stack glLoadIdentity(); // Reset the top of the modelview matrix to an identity matrix } void init() { glClearColor(1.0, 1.0, 0.0, 0.0); //sets the clear colour to yellow //glClear(GL_COLOR_BUFFER_BIT) in the display function //will clear the buffer to this colour. } void processKeys(Car& car) { if (keys[VK_UP]) { float cdx = sinf(radiansFromDegrees(car.ang)); float cdy = -cosf(radiansFromDegrees(car.ang)); car.dx += cdx; car.dy += cdy; } if (keys[VK_DOWN]) { float cdx = sinf(radiansFromDegrees(car.ang)); float cdy = -cosf(radiansFromDegrees(car.ang)); car.dx += -cdx; car.dy += -cdy; } if (keys[VK_LEFT]) { car.ang -= 2; } if (keys[VK_RIGHT]) { car.ang += 2; } } void update(Car& car) { car.x += car.dx*next_game_tick; } My WinMain code:
      /******************* WIN32 FUNCTIONS ***************************/ int WINAPI WinMain( HINSTANCE hInstance, // Instance HINSTANCE hPrevInstance, // Previous Instance LPSTR lpCmdLine, // Command Line Parameters int nCmdShow) // Window Show State { MSG msg; // Windows Message Structure bool done=false; // Bool Variable To Exit Loop Car car; car.x = 220; car.y = 140; car.dx = 0; car.dy = 0; car.ang = 0; AllocConsole(); FILE *stream; freopen_s(&stream, "CONOUT$", "w", stdout); // Create Our OpenGL Window if (!CreateGLWindow("OpenGL Win32 Example",screenWidth,screenHeight)) { return 0; // Quit If Window Was Not Created } while(!done) // Loop That Runs While done=FALSE { if (PeekMessage(&msg,NULL,0,0,PM_REMOVE)) // Is There A Message Waiting? { if (msg.message==WM_QUIT) // Have We Received A Quit Message? { done=true; // If So done=TRUE break; } else // If Not, Deal With Window Messages { TranslateMessage(&msg); // Translate The Message DispatchMessage(&msg); // Dispatch The Message } } else // If There Are No Messages { if(keys[VK_ESCAPE]) done = true; void processKeys(Car& car); //process keyboard while (game_is_running) { loops = 0; while (GetTickCount() > next_game_tick && loops < MAX_FRAMESKIP) { update(car); // update variables next_game_tick += SKIP_TICKS; loops++; } display(car); // Draw The Scene SwapBuffers(hDC); // Swap Buffers (Double Buffering) } } } // Shutdown KillGLWindow(); // Kill The Window return (int)(msg.wParam); // Exit The Program } //WIN32 Processes function - useful for responding to user inputs or other events. LRESULT CALLBACK WndProc( HWND hWnd, // Handle For This Window UINT uMsg, // Message For This Window WPARAM wParam, // Additional Message Information LPARAM lParam) // Additional Message Information { switch (uMsg) // Check For Windows Messages { case WM_CLOSE: // Did We Receive A Close Message? { PostQuitMessage(0); // Send A Quit Message return 0; // Jump Back } break; case WM_SIZE: // Resize The OpenGL Window { reshape(LOWORD(lParam),HIWORD(lParam)); // LoWord=Width, HiWord=Height return 0; // Jump Back } break; case WM_LBUTTONDOWN: { mouse_x = LOWORD(lParam); mouse_y = screenHeight - HIWORD(lParam); LeftPressed = true; } break; case WM_LBUTTONUP: { LeftPressed = false; } break; case WM_MOUSEMOVE: { mouse_x = LOWORD(lParam); mouse_y = screenHeight - HIWORD(lParam); } break; case WM_KEYDOWN: // Is A Key Being Held Down? { keys[wParam] = true; // If So, Mark It As TRUE return 0; // Jump Back } break; case WM_KEYUP: // Has A Key Been Released? { keys[wParam] = false; // If So, Mark It As FALSE return 0; // Jump Back } break; } // Pass All Unhandled Messages To DefWindowProc return DefWindowProc(hWnd,uMsg,wParam,lParam); }  
      game.cpp
    • By fs1
      I have been trying to see how the ID3DInclude, and how its methods Open and Close work.
      I would like to add a custom path for the D3DCompile function to search for some of my includes.
      I have not found any working example. Could someone point me on how to implement these functions? I would like D3DCompile to look at a custom C:\Folder path for some of the include files.
      Thanks
    • By stale
      I'm continuing to learn more about terrain rendering, and so far I've managed to load in a heightmap and render it as a tessellated wireframe (following Frank Luna's DX11 book). However, I'm getting some really weird behavior where a large section of the wireframe is being rendered with a yellow color, even though my pixel shader is hard coded to output white. 

      The parts of the mesh that are discolored changes as well, as pictured below (mesh is being clipped by far plane).

      Here is my pixel shader. As mentioned, I simply hard code it to output white:
      float PS(DOUT pin) : SV_Target { return float4(1.0f, 1.0f, 1.0f, 1.0f); } I'm completely lost on what could be causing this, so any help in the right direction would be greatly appreciated. If I can help by providing more information please let me know.
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DX11 Urho3D Graphics abstraction

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Hello,

I've stumbled upon Urho3D engine and found that it has a really nice and easy to read code structure.
I think the graphics abstraction looks really interesting and I like the idea of how it defers pipeline state changes until just before the draw call to resolve redundant state changes.
This is done by saving the state changes (blendEnabled/SRV changes/RTV changes) in member variables and just before the draw, apply the actual state changes using the graphics context.
It looks something like this (pseudo):

void PrepareDraw()
{
  if(renderTargetsDirty)
  {
      pD3D11DeviceContext->OMSetRenderTarget(mCurrentRenderTargets);
      renderTargetsDirty = false
  }
  if(texturesDirty)
  {
      pD3D11DeviceContext->PSSetShaderResourceView(..., mCurrentSRVs);
      texturesDirty = false
  }
  ....
  //Some more state changes
}

This all looked like a great design at first but I've found that there is one big issue with this which I don't really understand how it is solved in their case and how I would tackle it.
I'll explain it by example, imagine I have two rendertargets: my backbuffer RT and an offscreen RT.

Say I want to render my backbuffer to the offscreen RT and then back to the backbuffer (Just for the sake of the example).
You would do something like this:

//Render to the offscreen RT
pGraphics->SetRenderTarget(pOffscreenRT->GetRTV());
pGraphics->SetTexture(diffuseSlot, pDefaultRT->GetSRV())
pGraphics->DrawQuad()

pGraphics->SetTexture(diffuseSlot, nullptr); //Remove the default RT from input

//Render to the default (screen) RT
pGraphics->SetRenderTarget(nullptr); //Default RT
pGraphics->SetTexture(diffuseSlot, pOffscreenRT->GetSRV())
pGraphics->DrawQuad();

The problem here is that the second time the application loop comes around, the offscreen rendertarget is still bound as input ShaderResourceView when it gets set as a RenderTargetView because in Urho3D, the state of the RenderTargetView will always be changed before the ShaderResourceViews (see top code snippet) even when I set the SRV to nullptr before using it as a RTV like above causing errors because a resource can't be bound to both input and rendertarget.

What is usually the solution to this?

 

Thanks!

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Posted (edited)

I deal with a similar issue in my graphics library. My API is not exactly like what you've posted (it's closer to Vulkan/D3D12 with multiple resources being bound as a single set), but there's a similar problem that needs to be tackled in the Direct3D11 backend.

In my case, I just keep track of all SRVs and UAVs that are currently bound, and check for invalid combinations when a new SRV or UAV is bound. For example, if you try to bind an SRV for Texture A to the context, then I'll check if Texture A has any bound UAV's. If it does, then those are removed. Then, the SRV is bound to the context and added to the map that tracks SRV state. Same process when a UAV is bound.

A bit hand-wavey (I could elaborate if it doesn't make sense), but overall it's not a very complicated system. Urho3D might be doing something more clever than I am.

Edited by mellinoe

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That sounds pretty straight forward and I've thought of doing that as well.
Although:

7 hours ago, mellinoe said:

If it does, then those are removed

The downside of this, is that the graphics system would be doing "magic" just to make it work behind the back of the user while it might not have been intended behavior. It wouldn't point out when the user made an actual mistake, it would just solve it by unbinding the problematic resource while the user might not realize that.

I wonder if there's a cleaner solution for this.

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Posted (edited)
45 minutes ago, simco50 said:

The downside of this, is that the graphics system would be doing "magic" just to make it work behind the back of the user while it might not have been intended behavior.

I just treat this as a quirk of the Direct3D11 backend's state tracking behavior. It's not legal for users to bind incompatible resources to the pipeline through my library's regular API, and they would get a descriptive error message if they did that.

Nevertheless the D3D11 context might get into a state where there are resource conflicts after a sequence of legal operations, because unused resources aren't removed. I could probably aggressively purge those unused resources, but it would be unnecessary most of the time.

 

EDIT: To clarify, in response to this:

Quote

It wouldn't point out when the user made an actual mistake, it would just solve it by unbinding the problematic resource while the user might not realize that.

I'm only talking about the cases where the user hasn't made a mistake. If they try to actually do something illegal (e.g. bind a Texture as both read and read-write), then you should catch that separately and give them a descriptive error.

Edited by mellinoe

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That sounds like the right thing to do.
What I do now, is before a conflict, flush the staged states (submit the state changes to the context with PrepareDraw() in my case)
That works but I wonder if there's a smarter solution for this.

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I'm no longer actively involved in the development of this library, but thought I'd chime in..

When a rendertarget is set such that it's still also being bound as a SRV, what should happen is that the runtime cleans up the still bound SRV, and if you have the debug device flag enabled, you see this as output log spam.

(D3D11 WARNING: ID3D11DeviceContext::OMSetRenderTargets[AndUnorderedAccessViews]: Forcing VS shader resource slot 0 to NULL)

That's why the D3D11 Graphics::PrepareDraw() in Urho3D sets rendertargets first, then textures.

The situation also easily happens also in Urho3D's own rendering, when pingponged postprocesses are involved.

In case you see an actual rendering bug resulting from this (ie. black screen) please raise it in Urho3D's issue tracker.

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Setting render targets is very rare compared to setting textures, so I take the heavy-handed approach of unbinding all SRV's when setting new render-targets (and marking the SRV bindings as dirty so the next draw will rebind any that are required). In non-shipping builds, I also implement my own version of the D3D runtime warnings -- when binding a SRV, I check to see if it's already bound as a RTV/DSV/UAV, and assert if so.

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20 hours ago, cadaver said:

That's why the D3D11 Graphics::PrepareDraw() in Urho3D sets rendertargets first, then textures.

Yeah, that's what I saw. I actually had no idea DirectX solves it by itself and the warning doesn't really break anything.

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