I am following setting paths for 3D Objects in my book, what i want todo is add more paths instead of it reseting back to the right hand side of the screen, what do i need to change so the 3D Object goes along all the set paths,thanks for reading

void init_graphics(void)
{
    Path[0].x = -2.5f; Path[0].y = 1.0f; Path[0].z = 0.0f;
Path[1].x = 2.5f; Path[1].y = 1.0f; Path[1].z = 0.0f;
Path[2].x = 2.5f; Path[2].y = 1.0f; Path[2].z = 0.0f;
Path[3].x = -2.5f; Path[3].y = 1.0f; Path[3].z = 0.0f;
 
StartTime = (float)timeGetTime();
 
// create the vertices using the CUSTOMVERTEX struct
    CUSTOMVERTEX vertices[] = 
    {
        { 1.0f, -1.0f, 0.0f, D3DCOLOR_XRGB(0, 0, 255), },
        { 0.0f, 1.0f, 0.0f, D3DCOLOR_XRGB(0, 255, 0), },
        { -1.0f, -1.0f, 0.0f, D3DCOLOR_XRGB(255, 0, 0), },
    };
 
    // create a vertex buffer interface called v_buffer
    d3ddev->CreateVertexBuffer(3*sizeof(CUSTOMVERTEX),
                               0,
                               CUSTOMFVF,
                               D3DPOOL_MANAGED,
                               &v_buffer,
                               NULL);
 
    VOID* pVoid;    // a void pointer
 
    // lock v_buffer and load the vertices into it
    v_buffer->Lock(0, 0, (void**)&pVoid, 0);
    memcpy(pVoid, vertices, sizeof(vertices));
    v_buffer->Unlock();
}
 

void render_frame(void)
{
    d3ddev->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
 
    d3ddev->BeginScene();
 
    // select which vertex format we are using
    d3ddev->SetFVF(CUSTOMFVF);
 
    // SET UP THE PIPELINE
 
    D3DXMATRIX matRotateY;    // a matrix to store the rotation information
 
    static float index = 0.0f; index+=0.05f;    // an ever-increasing float value
 
    // build a matrix to rotate the model based on the increasing float value
    D3DXMatrixRotationY(&matRotateY, index);
 
    // tell Direct3D about our matrix
    d3ddev->SetTransform(D3DTS_WORLD, &matRotateY);
 
    D3DXMATRIX matView;    // the view transform matrix
 
    D3DXMatrixLookAtLH(&matView,
                       &D3DXVECTOR3 (0.0f, 0.0f, 5.0f),    // the camera position
                       &D3DXVECTOR3 (0.0f, 0.0f, 0.0f),    // the look-at position
                       &D3DXVECTOR3 (0.0f, 1.0f, 0.0f));    // the up direction
 
    d3ddev->SetTransform(D3DTS_VIEW, &matView);    // set the view transform to matView
 
    D3DXMATRIX matProjection;     // the projection transform matrix
 
    D3DXMatrixPerspectiveFovLH(&matProjection,
                               D3DXToRadian(45),    // the horizontal field of view
                               (FLOAT)SCREEN_WIDTH / (FLOAT)SCREEN_HEIGHT, // aspect ratio
                               0.1f,    // the near view-plane
                               100.0f);    // the far view-plane
 
    d3ddev->SetTransform(D3DTS_PROJECTION, &matProjection);    // set the projection
 
 
float Scalar = (float)timeGetTime();
Scalar = (Scalar -StartTime) * 0.0003f;
 
if(CurrentPath == 1)
{
stVector diff;
diff.x = Path[1].x - Path[0].x;
diff.y = Path[1].y - Path[0].y;
diff.z = Path[1].z - Path[0].z;
 
float len = (float)sqrt((diff.x * diff.x +
                   diff.y * diff.y +
diff.z * diff.z));
Scalar = Scalar / len;
objPos.x = (Path[1].x - Path[0].x) * Scalar + Path[0].x;
objPos.y = (Path[1].y - Path[0].y) * Scalar + Path[0].y;
objPos.z = (Path[1].z - Path[0].z) * Scalar + Path[0].z;
}
else
{
stVector diff;
diff.x = Path[3].x - Path[2].x;
diff.x = Path[3].y - Path[2].y;
diff.x = Path[3].z - Path[2].z;
 
float len = (float)sqrt((diff.x * diff.x +
                    diff.y * diff.y +
diff.z * diff.z));
 
Scalar = Scalar / len;
objPos.x = (Path[3].x - Path[2].x) * Scalar + Path[2].x;
objPos.y = (Path[3].y - Path[2].y) * Scalar + Path[2].y;
objPos.z = (Path[3].z - Path[2].z) * Scalar + Path[2].z;
}
 
if(Scalar >= 1.0f)
{
StartTime = (float)timeGetTime();
 
CurrentPath++;
 
if(CurrentPath > 2) CurrentPath = 1;
 
}
 
D3DXMATRIX mat;
//D3DXMatrixIdentity(&mat);
D3DXMatrixTranslation(&mat,objPos.x,objPos.y,objPos.z);
d3ddev->SetTransform(D3DTS_WORLD,&mat);
 
    // select the vertex buffer to display
    d3ddev->SetStreamSource(0, v_buffer, 0, sizeof(CUSTOMVERTEX));
 
    // copy the vertex buffer to the back buffer
    d3ddev->DrawPrimitive(D3DPT_TRIANGLELIST, 0, 1);
 
    d3ddev->EndScene();
 
    d3ddev->Present(NULL, NULL, NULL, NULL);
}

 

Thanks for replying,i have done what you suggested but it seems the triangle still seems to go from right to left and not back again

void SetPath(UINT uiStart, UINT uiEnd,float Scalar)
{
diff.x = Path[uiEnd].x - Path[uiStart].x;
diff.y = Path[uiEnd].y - Path[uiStart].y;
diff.z = Path[uiEnd].z - Path[uiStart].z;
 
float len = (float)sqrt((diff.x * diff.x +
  diff.y * diff.y +
diff.z * diff.z));
Scalar = Scalar / len;
objPos.x = (Path[uiEnd].x - Path[uiStart].x) * Scalar + Path[uiStart].x;
objPos.y = (Path[uiEnd].y - Path[uiStart].y) * Scalar + Path[uiStart].y;
objPos.z = (Path[uiEnd].z - Path[uiStart].z) * Scalar + Path[uiStart].z;
}
 
//Paths

 Path[0].x = -0.1f; Path[0].y = 0.0f; Path[0].z = 0.0f;
  Path[1].x =  0.1f; Path[1].y = 0.0f; Path[1].z = 0.0f;
  Path[2].x =  0.1f; Path[2].y = 0.0f; Path[2].z = 0.0f;
  Path[3].x = -0.1f; Path[3].y = 0.0f; Path[3].z = 0.0f;
  Path[4].x = 0.1f; Path[4].y = 0.0f; Path[4].z = 0.0f;
  Path[5].x = -0.1f; Path[5].y = 0.0f; Path[5].z = 0.0f;
 
//using the function

for (UINT i = 0; i < MaxPath; i++)
{
SetPath(i, i+1,Scalar);
}
 

I am kind of confused now, i did comment out the below code on your first suggestion,now use and not the forloop right?

if(Scalar >= 1.0f)
{
StartTime = (float)timeGetTime();
 
CurrentPath++;
 
if(CurrentPath > 2) CurrentPath = 1;
 
}

now i have

void render_frame(void)
{
    d3ddev->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
 
    d3ddev->BeginScene();
 
    // select which vertex format we are using
    d3ddev->SetFVF(CUSTOMFVF);
 
    // SET UP THE PIPELINE
 
    D3DXMATRIX matRotateY;    // a matrix to store the rotation information
 
    static float index = 0.0f; index+=0.05f;    // an ever-increasing float value
 
    // build a matrix to rotate the model based on the increasing float value
    D3DXMatrixRotationY(&matRotateY, index);
 
    // tell Direct3D about our matrix
    d3ddev->SetTransform(D3DTS_WORLD, &matRotateY);
 
    D3DXMATRIX matView;    // the view transform matrix
 
    D3DXMatrixLookAtLH(&matView,
                       &D3DXVECTOR3 (0.0f, 0.0f, 5.0f),    // the camera position
                       &D3DXVECTOR3 (0.0f, 0.0f, 0.0f),    // the look-at position
                       &D3DXVECTOR3 (0.0f, 1.0f, 0.0f));    // the up direction
 
    d3ddev->SetTransform(D3DTS_VIEW, &matView);    // set the view transform to matView
 
    D3DXMATRIX matProjection;     // the projection transform matrix
 
    D3DXMatrixPerspectiveFovLH(&matProjection,
                               D3DXToRadian(45),    // the horizontal field of view
                               (FLOAT)SCREEN_WIDTH / (FLOAT)SCREEN_HEIGHT, // aspect ratio
                               0.1f,    // the near view-plane
                               100.0f);    // the far view-plane
 
    d3ddev->SetTransform(D3DTS_PROJECTION, &matProjection);    // set the projection
 
 
float Scalar = (float)timeGetTime();
Scalar = (Scalar - StartTime) * 0.003f;
 
if(Scalar >= 1.0f)
{
StartTime = (float)timeGetTime();
 
CurrentPath++;
 
if(CurrentPath > MaxPath) CurrentPath = 0;
 
}
 
SetPath(CurrentPath, CurrentPath + 1);
    CurrentPath++;
 
 
D3DXMATRIX mat;
//D3DXMatrixIdentity(&mat);
D3DXMatrixTranslation(&mat,objPos.x,objPos.y,objPos.z);
d3ddev->SetTransform(D3DTS_WORLD,&mat);
 
    // select the vertex buffer to display
    d3ddev->SetStreamSource(0, v_buffer, 0, sizeof(CUSTOMVERTEX));
 
    // copy the vertex buffer to the back buffer
    d3ddev->DrawPrimitive(D3DPT_TRIANGLELIST, 0, 1);
 
    d3ddev->EndScene();
 
    d3ddev->Present(NULL, NULL, NULL, NULL);
}

Thanks alot for the quick respone, so now its doing a teleport effect and not actually moving from the points, but its going through the paths, i dont think changing the scaler speed will fix it as its already set to slow

it seems this condition affects how far the triangle moves

if(Scalar >= 1.0f)

because that would only be for -1.0f and 1.0f, so what happens if the path is like -3.0f and 3.0f, a bigger scaler etc, because visually it just moves abit and goes to the next path