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    • 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 lxjk
      Hi guys,
      There are many ways to do light culling in tile-based shading. I've been playing with this idea for a while, and just want to throw it out there.
      Because tile frustums are general small compared to light radius, I tried using cone test to reduce false positives introduced by commonly used sphere-frustum test.
      On top of that, I use distance to camera rather than depth for near/far test (aka. sliced by spheres).
      This method can be naturally extended to clustered light culling as well.
      The following image shows the general ideas

       
      Performance-wise I get around 15% improvement over sphere-frustum test. You can also see how a single light performs as the following: from left to right (1) standard rendering of a point light; then tiles passed the test of (2) sphere-frustum test; (3) cone test; (4) spherical-sliced cone test
       

       
      I put the details in my blog post (https://lxjk.github.io/2018/03/25/Improve-Tile-based-Light-Culling-with-Spherical-sliced-Cone.html), GLSL source code included!
       
      Eric
    • By Fadey Duh
      Good evening everyone!

      I was wondering if there is something equivalent of  GL_NV_blend_equation_advanced for AMD?
      Basically I'm trying to find more compatible version of it.

      Thank you!
    • By Jens Eckervogt
      Hello guys, 
       
      Please tell me! 
      How do I know? Why does wavefront not show for me?
      I already checked I have non errors yet.
      using OpenTK; using System.Collections.Generic; using System.IO; using System.Text; namespace Tutorial_08.net.sourceskyboxer { public class WaveFrontLoader { private static List<Vector3> inPositions; private static List<Vector2> inTexcoords; private static List<Vector3> inNormals; private static List<float> positions; private static List<float> texcoords; private static List<int> indices; public static RawModel LoadObjModel(string filename, Loader loader) { inPositions = new List<Vector3>(); inTexcoords = new List<Vector2>(); inNormals = new List<Vector3>(); positions = new List<float>(); texcoords = new List<float>(); indices = new List<int>(); int nextIdx = 0; using (var reader = new StreamReader(File.Open("Contents/" + filename + ".obj", FileMode.Open), Encoding.UTF8)) { string line = reader.ReadLine(); int i = reader.Read(); while (true) { string[] currentLine = line.Split(); if (currentLine[0] == "v") { Vector3 pos = new Vector3(float.Parse(currentLine[1]), float.Parse(currentLine[2]), float.Parse(currentLine[3])); inPositions.Add(pos); if (currentLine[1] == "t") { Vector2 tex = new Vector2(float.Parse(currentLine[1]), float.Parse(currentLine[2])); inTexcoords.Add(tex); } if (currentLine[1] == "n") { Vector3 nom = new Vector3(float.Parse(currentLine[1]), float.Parse(currentLine[2]), float.Parse(currentLine[3])); inNormals.Add(nom); } } if (currentLine[0] == "f") { Vector3 pos = inPositions[0]; positions.Add(pos.X); positions.Add(pos.Y); positions.Add(pos.Z); Vector2 tc = inTexcoords[0]; texcoords.Add(tc.X); texcoords.Add(tc.Y); indices.Add(nextIdx); ++nextIdx; } reader.Close(); return loader.loadToVAO(positions.ToArray(), texcoords.ToArray(), indices.ToArray()); } } } } } And It have tried other method but it can't show for me.  I am mad now. Because any OpenTK developers won't help me.
      Please help me how do I fix.

      And my download (mega.nz) should it is original but I tried no success...
      - Add blend source and png file here I have tried tried,.....  
       
      PS: Why is our community not active? I wait very longer. Stop to lie me!
      Thanks !
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OpenGL Model View Projection matrices

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The following code retrieves the model view and projection matrices based on my camera, and I'm wondering if I have the right matrices in the get_:model_matrix, get_view_matrix and get_projection_matrix functions:

 

#include "matrix_utils.h"


void multiply_4x4_matrices(float (&in_a)[16], float (&in_b)[16], float (&out)[16])
{
 //   matrix layout:
 //    
 //   [0 4  8 12]
 //   [1 5  9 13]
 //   [2 6 10 14]
 //   [3 7 11 15]
    
    out[0] = in_a[0] * in_b[0] + in_a[4] * in_b[1] + in_a[8] * in_b[2] + in_a[12] * in_b[3];
    out[1] = in_a[1] * in_b[0] + in_a[5] * in_b[1] + in_a[9] * in_b[2] + in_a[13] * in_b[3];
    out[2] = in_a[2] * in_b[0] + in_a[6] * in_b[1] + in_a[10] * in_b[2] + in_a[14] * in_b[3];
    out[3] = in_a[3] * in_b[0] + in_a[7] * in_b[1] + in_a[11] * in_b[2] + in_a[15] * in_b[3];
    out[4] = in_a[0] * in_b[4] + in_a[4] * in_b[5] + in_a[8] * in_b[6] + in_a[12] * in_b[7];
    out[5] = in_a[1] * in_b[4] + in_a[5] * in_b[5] + in_a[9] * in_b[6] + in_a[13] * in_b[7];
    out[6] = in_a[2] * in_b[4] + in_a[6] * in_b[5] + in_a[10] * in_b[6] + in_a[14] * in_b[7];
    out[7] = in_a[3] * in_b[4] + in_a[7] * in_b[5] + in_a[11] * in_b[6] + in_a[15] * in_b[7];
    out[8] = in_a[0] * in_b[8] + in_a[4] * in_b[9] + in_a[8] * in_b[10] + in_a[12] * in_b[11];
    out[9] = in_a[1] * in_b[8] + in_a[5] * in_b[9] + in_a[9] * in_b[10] + in_a[13] * in_b[11];
    out[10] = in_a[2] * in_b[8] + in_a[6] * in_b[9] + in_a[10] * in_b[10] + in_a[14] * in_b[11];
    out[11] = in_a[3] * in_b[8] + in_a[7] * in_b[9] + in_a[11] * in_b[10] + in_a[15] * in_b[11];
    out[12] = in_a[0] * in_b[12] + in_a[4] * in_b[13] + in_a[8] * in_b[14] + in_a[12] * in_b[15];
    out[13] = in_a[1] * in_b[12] + in_a[5] * in_b[13] + in_a[9] * in_b[14] + in_a[13] * in_b[15];
    out[14] = in_a[2] * in_b[12] + in_a[6] * in_b[13] + in_a[10] * in_b[14] + in_a[14] * in_b[15];
    out[15] = in_a[3] * in_b[12] + in_a[7] * in_b[13] + in_a[11] * in_b[14] + in_a[15] * in_b[15];
}

/*
void multiply_4x4_matrices(float (&in_a)[16], float (&in_b)[16], float (&out)[16])
{
    for(int i = 0; i < 4; i++)
    {
        for(int j = 0; j < 4; j++)
        {
            out[4*i + j] = 0;
            
            for (int k = 0; k < 4; k++)
                out[4*i + j] += in_a[4*k + j] * in_b[4*i + k];
        }
    }
}
B*/
    

void init_perspective_camera(float fovy, float aspect, float znear, float zfar,
                             float eyex, float eyey, float eyez, float centrex, float centrey,
                             float centrez, float upx, float upy, float upz,
                             float (&model_matrix)[16],
                             float (&view_matrix)[16],
                             float (&projection_matrix)[16],
                             float (&projection_model_view_matrix)[16])
{
    get_model_matrix(eyex, eyey, eyez, centrex, centrey, centrez, upx, upy, upz, model_matrix);
    get_view_matrix(eyex, eyey, eyez, view_matrix);
    get_projection_matrix(fovy, aspect, znear, zfar, projection_matrix);

    float temp_matrix[16];
    multiply_4x4_matrices(model_matrix, view_matrix, temp_matrix);
    multiply_4x4_matrices(projection_matrix, temp_matrix, projection_model_view_matrix);
}





void get_model_matrix(float eyex, float eyey, float eyez, float centrex, float centrey, float centrez, float upx, float upy, float upz, float (&mat)[16])
{
    // https://www.opengl.org/sdk/docs/man2/xhtml/gluLookAt.xml
    // http://www.cs.virginia.edu/~gfx/Courses/1999/intro.fall99.html/lookat.html
    vertex_3 f, up, s, u;
            
    f.x = centrex - eyex;
    f.y = centrey - eyey;
    f.z = centrez - eyez;
    f.normalize();
    
    up.x = upx;
    up.y = upy;
    up.z = upz;
    up.normalize();
    
    s = f.cross(up);
    s.normalize();
    
    u = s.cross(f);
    u.normalize();
    
    mat[0] = s.x;  mat[4] = s.y;  mat[8] = s.z;   mat[12] = 0;
    mat[1] = u.x;  mat[5] = u.y;  mat[9] = u.z;   mat[13] = 0;
    mat[2] = -f.x; mat[6] = -f.y; mat[10] = -f.z; mat[14] = 0;
    mat[3] = 0;    mat[7] = 0;    mat[11] = 0;    mat[15] = 1;
}



void get_view_matrix(float eyex, float eyey, float eyez, float (&in_a)[16])
{
    // https://www.opengl.org/sdk/docs/man2/xhtml/gluLookAt.xml
    // http://www.cs.virginia.edu/~gfx/Courses/1999/intro.fall99.html/lookat.html

    in_a[0] = 1; in_a[4] = 0; in_a[8] = 0;  in_a[12] = -eyex;
    in_a[1] = 0; in_a[5] = 1; in_a[9] = 0;  in_a[13] = -eyey;
    in_a[2] = 0; in_a[6] = 0; in_a[10] = 1; in_a[14] = -eyez;
    in_a[3] = 0; in_a[7] = 0; in_a[11] = 0; in_a[15] = 1;
}

void get_projection_matrix(float fovy, float aspect, float znear, float zfar, float (&in_a)[16])
{
    // https://www.opengl.org/sdk/docs/man2/xhtml/gluPerspective.xml
    const float pi = 4.0f*atanf(1.0);
    
    // Convert fovy to radians, then divide by 2
    float       f = 1.0f / tan(fovy/360.0f*pi);
    
    in_a[0] = f/aspect; in_a[4] = 0; in_a[8] = 0;                              in_a[12] = 0;
    in_a[1] = 0;        in_a[5] = f; in_a[9] = 0;                              in_a[13] = 0;
    in_a[2] = 0;        in_a[6] = 0; in_a[10] = (zfar + znear)/(znear - zfar); in_a[14] = (2.0f*zfar*znear)/(znear - zfar);
    in_a[3] = 0;        in_a[7] = 0; in_a[11] = -1;                            in_a[15] = 0;
}

 

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Your model matrix should not need the eye to be calculated. A model matrix is the transformation that converts an objects local coordinates to world coordinates. The location of the camera is irrelevant to the model matrix.

Your view matrix should convert world coordinates to camera coordinates. (This is the inverse of the camera's model matrix)

I highly recommend you use a Matrix class instead of passing around float arrays everywhere. Finding an existing matrix library would be even better.

EDIT: It looks like the eye coordinates in your model code refer to the direction that specific object is looking. In that case that looks fine, your view matrix at the moment can only translate the camera. You have no code to rotate your camera, is this intentional? Edited by HappyCoder

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I rotate the camera around a fixed point (look_at = 0,0,0) and pass that rotation in as the eye position. This is calculated by the C++ code.

 

I think I figured out the right matrices for the right calls (in matrix_utils.cpp). Attached is the full code, including the shaders and a sample STL file to view.

 

 

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Here matrix functions I use ( left-handed ) :

void CMatrix4::PerspectiveFOV( const float Fov, const float Ratio, const float Near, const float Far )
{
  const float YScale = 1.0f / CMath::Tan( Fov * 0.5f );
  const float XScale = YScale / Ratio;
  const float Coeff = Far / ( Far - Near );
  m44[ 0 ][ 0 ] = XScale; m44[ 0 ][ 1 ] = 0.0f;   m44[ 0 ][ 2 ] = 0.0f;  m44[ 0 ][ 3 ] = 0.0f;
  m44[ 1 ][ 0 ] = 0.0f;   m44[ 1 ][ 1 ] = YScale; m44[ 1 ][ 2 ] = 0.0f;  m44[ 1 ][ 3 ] = 0.0f;
  m44[ 2 ][ 0 ] = 0.0f;   m44[ 2 ][ 1 ] = 0.0f;   m44[ 2 ][ 2 ] = Coeff; m44[ 2 ][ 3 ] = -Near * Coeff;
  m44[ 3 ][ 0 ] = 0.0f;   m44[ 3 ][ 1 ] = 0.0f;   m44[ 3 ][ 2 ] = 1.0f;  m44[ 3 ][ 3 ] = 0.0f;
}

void CMatrix4::LookAt( const CVector3& From, const CVector3& To, const CVector3& Up )
{
  const CVector3 ZAxis = ( To - From ).Normalized();
  const CVector3 XAxis = VectorCross( Up, ZAxis ).Normalized();
  const CVector3 YAxis = VectorCross( ZAxis, XAxis ).Normalized();
  m44[ 0 ][ 0 ] = XAxis.x; m44[ 0 ][ 1 ] = XAxis.y; m44[ 0 ][ 2 ] = XAxis.z; m44[ 0 ][ 3 ] = -VectorDot( XAxis, From );
  m44[ 1 ][ 0 ] = YAxis.x; m44[ 1 ][ 1 ] = YAxis.y; m44[ 1 ][ 2 ] = YAxis.z; m44[ 1 ][ 3 ] = -VectorDot( YAxis, From );
  m44[ 2 ][ 0 ] = ZAxis.x; m44[ 2 ][ 1 ] = ZAxis.y; m44[ 2 ][ 2 ] = ZAxis.z; m44[ 2 ][ 3 ] = -VectorDot( ZAxis, From );
  m44[ 3 ][ 0 ] = 0.0f;    m44[ 3 ][ 1 ] = 0.0f;    m44[ 3 ][ 2 ] = 0.0f;    m44[ 3 ][ 3 ] = 1.0f;
}
Edited by Alundra

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As has been pointed out, but will say again, model and projection matrices should have nothing to do with the camera. The camera should provide a view matrix. That's it.

An individual object should provide its own world matrix to be moved from model space to world space, and the projection matrix is likely to just be a constant for the lifetime of the game.

All the camera should be concerned with is using its position and orientation to provide a view matrix to take world positions to view space.

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A camera component has a view matrix and projection matrix.

The projection matrix is updated when the camera properties changes, the view matrix is updated when the camera moves.

You can also keep a ViewProjection matrix in the camera component to share it to avoid depth test issues.

Edited by Alundra

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Thanks for the information!

 

I moved the look_at + translate code into the view matrix, and the perspective code into the projection matrix. Finally, the camera uses an identity matrix for the model matrix.

Edited by taby

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