PureBasic Forums - English

Posted: **Wed Jul 01, 2015 4:23 pm**

it is confusing to know where is triangle number 0 or 100 or to get a List of all triangles vertices coordinates in the mesh. so look this example, it uses a custom plane from MeshManualFlag.pb (because it has many squares)
a sphere is positioned in the middle of triangle 105, and every space key press will move it to the next triangle by calling procedure triangle(num). if you press D then that triangle will go deep a little (like a hole) , W will toggle wire/solid frame.
haven't thought yet of using a mouse to choose specific triangle

Code: Select all

Enumeration
#mesh
#cube
#sphere

EndEnumeration

Global Dim MeshData.PB_MeshVertex(0)
Global Dim MeshDataInd.PB_MeshFace(0)

#CameraSpeed = 0.1
#NbX=10
#NbZ=10

Define.f KeyX, KeyY, MouseX, MouseY

Global Dim MeshData.PB_MeshVertex(0)
Global Dim MeshDataInd.PB_MeshFace(0)


Declare CreatePlane2()
Declare triangle(num.l)

  InitEngine3D()
  
  InitSprite()
  InitKeyboard()
  InitMouse()
  
  ExamineDesktops()
  OpenWindow(0, 0, 0, DesktopWidth(0), DesktopHeight(0), "Space : to move the ball to the next triangle ...W : wire/solid frame,....D: toggle deform ... arrow keys+mouse for cam ", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
   OpenWindowedScreen(WindowID(0), 0, 0, DesktopWidth(0), DesktopHeight(0)-10, 0, 0, 0)   
   
    Add3DArchive(#PB_Compiler_Home + "Examples/3D/Data/Packs/skybox.zip", #PB_3DArchive_Zip)
    Add3DArchive(#PB_Compiler_Home + "Examples/3D/Data/Scripts", #PB_3DArchive_FileSystem)
    Add3DArchive(#PB_Compiler_Home + "Examples/3D/Data/Textures", #PB_3DArchive_FileSystem)
    Add3DArchive(#PB_Compiler_Home + "Examples/3D/Data/Models", #PB_3DArchive_FileSystem)
    Add3DArchive(".", #PB_3DArchive_FileSystem)
    Parse3DScripts()
    
    Global monitor=CreateSprite(#PB_Any,120,40)
    ;-Material 
    CreateMaterial(1, LoadTexture(1, "Geebee2.bmp"))
    DisableMaterialLighting(1, 1)
    MaterialCullingMode(1, 1)
    SetMaterialColor(1, #PB_Material_SelfIlluminationColor, RGB(255, 255, 255))
    
    CreateMaterial(0, LoadTexture(0, "White.jpg"))
    MaterialShadingMode(0, #PB_Material_Wireframe)
    MaterialCullingMode(0, #True)
    DisableMaterialLighting(0, #True)
       
    ;CreateMaterial(6, LoadTexture(6, "MRAMOR6X6.jpg"))
    CreateMaterial(6, LoadTexture(6, "MRAMOR6X6.jpg"))
    MaterialShadingMode(6, #PB_Material_Wireframe)
    MaterialCullingMode(6, #True)
    DisableMaterialLighting(6, #True)
    
    CreateSphere(#sphere, 0.1)
    CreateEntity(#sphere, MeshID(#sphere),  MaterialID(1) ,0,2,0)

    ;-Mesh ; draw the plane with many triangles
    CreatePlane2()
    
    ;-Camera
    CreateCamera(0, 0, 0, 100, 100)
    MoveCamera(0,0,10,10, #PB_Absolute)
    CameraLookAt(0, 0, 0, 0)
    CameraBackColor(0, RGB(0,0,0))
    
    ;-Light
    CreateLight(0, RGB(255, 255, 255), 0, 2, 30)
    AmbientColor(RGB(255, 255, 255))
            
    GetMeshData(#mesh,0, MeshData(), #PB_Mesh_Vertex | #PB_Mesh_Color | #PB_Mesh_Normal | #PB_Mesh_Tangent , 0, MeshVertexCount(#Mesh)-1)
    GetMeshData(#mesh,0, MeshDataInd(), #PB_Mesh_Face, 0, MeshIndexCount(#mesh, 0)-1)

    
    Global tri=105
    triangle(tri)
      
    SetMeshData(#mesh,0, MeshData(), #PB_Mesh_Vertex | #PB_Mesh_Color | #PB_Mesh_Normal | #PB_Mesh_Tangent, 0, MeshVertexCount(#mesh)-1)
    UpdateMeshBoundingBox(#mesh)
    
    Global deform = 0
    Repeat
      WindowEvent()
      If ExamineKeyboard()
        
       If KeyboardReleased(#PB_Key_W)
          If wireFrame
          MaterialShadingMode(6, #PB_Material_Wireframe)
          wireFrame ! 1
        Else 
          MaterialShadingMode(6, #PB_Material_Solid)
          wireFrame ! 1
        EndIf
      EndIf
      
      ;00000000000000000000000000000000000000000000000000000000000000000000000000000
      If KeyboardReleased(#PB_Key_D)
         deform ! 1
        
      EndIf
;;oooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo      
                
        If KeyboardReleased(#PB_Key_Space)
          tri+1
          If tri*3 > MeshIndexCount(#mesh)-1
            tri=0
          EndIf
          
          triangle(tri)
                    
        EndIf
        
        If KeyboardPushed(#PB_Key_Up)
          KeyY = -#CameraSpeed
        ElseIf KeyboardPushed(#PB_Key_Down)
          KeyY = #CameraSpeed
        Else
          KeyY = 0
        EndIf
        
        If KeyboardPushed(#PB_Key_Left)
          KeyX = -#CameraSpeed
        ElseIf KeyboardPushed(#PB_Key_Right)
          KeyX = #CameraSpeed
        Else
          KeyX = 0
        EndIf
      EndIf
      If ExamineMouse()
        MouseX = -(MouseDeltaX()/10)
        MouseY = -(MouseDeltaY()/10)
      EndIf
      MoveCamera  (0, KeyX, 0, KeyY)
      RotateCamera(0,  MouseY, MouseX, 0, #PB_Relative) 
            
      RenderWorld()
      
      StartDrawing(SpriteOutput(monitor))
      DrawText(5,5,"the ball in Triangle " )
      DrawText(5,20,"Triangle= " +"      ")
      DrawText(5,20,"Triangle= " +Str(tri))
      StopDrawing()
      DisplaySprite(monitor,0,0)
      
      FlipBuffers()
    Until KeyboardPushed(#PB_Key_Escape) Or Quit = 1
    

End


Procedure CreatePlane2()
  
  CreateMesh(#mesh, #PB_Mesh_TriangleList, #PB_Mesh_Dynamic)
  
  Protected.l a, b, c, Nb
  Protected.w P1, P2, P3, P4
    
  For b=0 To #Nbz
    For a=0 To #NbX
          
      MeshVertexPosition(a - #NbX/2, y, b - #Nbz/2)
      MeshVertexNormal(0,1,0)
      MeshVertexColor(RGB(255,255,255))
      MeshVertexTextureCoordinate(a/#NbX, b/#Nbz)
    Next a
  Next b
  
  Nb=#NbX+1
  For b=0 To #NbZ-1
    For a=0 To #NbX-1
      P1=a+(b*Nb)
      P2=P1+1
      P3=a+(b+1)*Nb
      P4=P3+1
      
      MeshFace(P3, P2, P1)
      MeshFace(P2, P3, P4)
    Next
  Next
  
  FinishMesh(#True)
  UpdateMeshBoundingBox(#mesh)
  SetMeshMaterial(#mesh, MaterialID(6))
    
  CreateEntity(#mesh, MeshID(#mesh), #PB_Material_None)
    
  GetMeshData(#mesh,0, MeshData(), #PB_Mesh_Vertex | #PB_Mesh_Color | #PB_Mesh_Normal | #PB_Mesh_Tangent, 0, MeshVertexCount(#mesh, 0)-1)
  GetMeshData(#mesh,0, MeshDataInd(), #PB_Mesh_Face, 0, MeshIndexCount(#mesh, 0)-1)
  
EndProcedure

Procedure triangle(num.l)
    i = 3*num 
  
    x1.f = MeshData(MeshDataInd(i)\Index)\x
    y1.f = MeshData(MeshDataInd(i)\Index)\y
    z1.f = MeshData(MeshDataInd(i)\Index)\z
    ;MeshData(MeshDataInd(i)\Index)\Color = RGB(0,0,255)
    
    x2.f = MeshData(MeshDataInd(i+1)\Index)\x
    y2.f = MeshData(MeshDataInd(i+1)\Index)\y
    z2.f = MeshData(MeshDataInd(i+1)\Index)\z
    ;MeshData(MeshDataInd(i+1)\Index)\Color = RGB(255,0,0)
    
    x3.f = MeshData(MeshDataInd(i+2)\Index)\x 
    y3.f = MeshData(MeshDataInd(i+2)\Index)\y 
    z3.f = MeshData(MeshDataInd(i+2)\Index)\z 
    
    If deform ; to deform the triangle vertices or not
    MeshData(MeshDataInd(i)\Index)\y - 0.3
    MeshData(MeshDataInd(i+1)\Index)\y - 0.3
    MeshData(MeshDataInd(i+2)\Index)\y - 0.3
    EndIf
    ;MeshData(MeshDataInd(i+2)\Index)\Color = RGB(0,255,0)
    SetMeshData(#mesh,0, MeshData(), #PB_Mesh_Vertex | #PB_Mesh_Color | #PB_Mesh_Normal | #PB_Mesh_Tangent, 0, MeshVertexCount(#mesh)-1)
    ; position a sphere at the center of the triangle 
    MoveEntity(#sphere, (x1+x2+x3)/3,(y1+y2+y3)/3,(z1+z2+z3)/3, #PB_Absolute)
  EndProcedure

but what about a known mesh such as robot or sphere or cylinder ? the solution is : first make a copy from it over a new created dynamic mesh, and then color triangle number 0 (the color will spread to a nearby triangle since the vertices are shared)
the amusing fact is if we use EntityLookAt, in the case of a cube the triangle 0 will be on the rear side of the cube looking at some point. but this is not a rule for every mesh, the triangle 0 in the robot is in his right hand (you need to move the camera away to see the robot) this is determined initially by the designer.

Code: Select all

Enumeration
#mesh
#cube
#cubeTemp
#sphere

EndEnumeration


Global Dim MeshData.PB_MeshVertex(0)
Global Dim MeshDataInd.PB_MeshFace(0)

#CameraSpeed = 0.1

Define.f KeyX, KeyY, MouseX, MouseY

Global Dim MeshData.PB_MeshVertex(0)
Global Dim MeshDataInd.PB_MeshFace(0)
Global v.l

If InitEngine3D()
  
  InitSprite()
  InitKeyboard()
  InitMouse()
  
  ExamineDesktops()
  OpenWindow(0, 0, 0, DesktopWidth(0), DesktopHeight(0), "press W wire/Solid frame, .... arrow keys+mouse for the camera ", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
   OpenWindowedScreen(WindowID(0), 0, 0, DesktopWidth(0), DesktopHeight(0)-10, 0, 0, 0)   
   
   Add3DArchive(#PB_Compiler_Home + "Examples/3D/Data/Packs/skybox.zip", #PB_3DArchive_Zip)
    Add3DArchive(#PB_Compiler_Home + "Examples/3D/Data/Scripts", #PB_3DArchive_FileSystem)
    Add3DArchive(#PB_Compiler_Home + "Examples/3D/Data/Textures", #PB_3DArchive_FileSystem)
    Add3DArchive(#PB_Compiler_Home + "Examples/3D/Data/Models", #PB_3DArchive_FileSystem)
    Add3DArchive(".", #PB_3DArchive_FileSystem)
    Parse3DScripts()
    
    ;-Material 
    CreateMaterial(1, LoadTexture(1, "Wood.jpg"))
    DisableMaterialLighting(1, 1)
    MaterialCullingMode(1, 1)
    MaterialShadingMode(1, #PB_Material_Wireframe)
    SetMaterialColor(1, #PB_Material_SelfIlluminationColor, RGB(255, 255, 255))
    
    CreateMaterial(0, LoadTexture(0, "White.jpg"))
    ;MaterialShadingMode(0, #PB_Material_Wireframe)
    MaterialCullingMode(0, #True)
    DisableMaterialLighting(0, #True)
       
    CreateMaterial(6, LoadTexture(6, "ground_diffuse.png"))

     
    ;-Camera
    CreateCamera(0, 0, 0, 100, 100)
    MoveCamera(0,-6,4,4, #PB_Absolute)
    CameraLookAt(0, 0, 0, 0)
    CameraBackColor(0, RGB(0,0,0))
    
    ;-Light
    CreateLight(0, RGB(255, 255, 255), 5, 15, 5)
    AmbientColor(RGB(255, 255, 255))
          
    
    CreateCube(#cubeTemp, 1) ; the wanted mesh , you can also use any of the following
    ;LoadMesh(#cubeTemp, "robot.mesh") ; note this mesh is very big
    ;CreateSphere(#cubeTemp, 1)
    ;CreateCylinder(#cubeTemp, 0.4, 3)
    ;TransformMesh(#cubeTemp, 0,0,0, 0.5 ,0.5, 0.5, 90,0,0) ; rotate the mesh 90 degree for the cylinder to appear vertical on the surface
    ;UpdateMeshBoundingBox(#cubeTemp)
          
    CreateMesh(#cube, #PB_Mesh_TriangleList, #PB_Mesh_Dynamic); this is what we want to copy the mesh to
    
    GetMeshData(#cubeTemp,0, MeshData(), #PB_Mesh_Vertex | #PB_Mesh_Color | #PB_Mesh_Normal | #PB_Mesh_Tangent, 0, MeshVertexCount(#cubeTemp, 0)-1)
    GetMeshData(#cubeTemp,0, MeshDataInd(), #PB_Mesh_Face, 0, MeshIndexCount(#cubeTemp, 0)-1)
    
    
    ArrSize = ArraySize(MeshData())
    ;Debug ArrSize
  ; drawing the vertices one by one using the info from the MeshData
  For c=0 To ArrSize
      
      x.f = MeshData(c)\x 
      y.f = MeshData(c)\y
      z.f = MeshData(c)\z
      MeshVertexPosition(x,y,z)
      MeshVertexColor(RGB(255,255,255))
      MeshVertexTextureCoordinate(MeshData(c)\u, MeshData(c)\v) 
      
  Next   
   
   ArrSizeInd = ArraySize(MeshDataInd()) 
   For i=0 To ArrSizeInd Step 3
     ;constructing the triangles like the original mesh
     MeshFace(MeshDataInd(i)\Index, MeshDataInd(i+1)\Index,MeshDataInd(i+2)\Index)
   Next
   
   FinishMesh(#True)
   CreateEntity(#cube, MeshID(#cube), MaterialID(0), 0 ,1 ,0 )
   
   GetMeshData(#cube,0, MeshData(), #PB_Mesh_Vertex | #PB_Mesh_Color | #PB_Mesh_Normal | #PB_Mesh_Tangent, 0, MeshVertexCount(#cube, 0)-1)
   GetMeshData(#cube,0, MeshDataInd(), #PB_Mesh_Face, 0, MeshIndexCount(#cube, 0)-1)
    
   ;Debug MeshIndexCount(#cube); = 36
   
   ;change the color of the first triangle in the mesh
   ind=0
    MeshData(MeshDataInd(ind)\Index)\Color =   RGB(255,0,0)
    MeshData(MeshDataInd(ind+1)\Index)\Color = RGB(0,255,0)
    MeshData(MeshDataInd(ind+2)\Index)\Color = RGB(0,0,255)
    
    SetMeshData(#cube,0, MeshData(), #PB_Mesh_Vertex | #PB_Mesh_Color | #PB_Mesh_Normal | #PB_Mesh_Tangent, 0, MeshVertexCount(#cube)-1)
    
    ; extra amusements
    EntityFixedYawAxis(#cube, #True, 0,1,0)
    EntityLookAt(#cube, 0,0,0) 
    wireFrame = 1
    Repeat
      WindowEvent()
      If ExamineKeyboard()
        
       If KeyboardReleased(#PB_Key_W)
          If wireFrame
          MaterialShadingMode(0, #PB_Material_Wireframe)
          wireFrame ! 1
        Else 
          MaterialShadingMode(0, #PB_Material_Solid)
          wireFrame ! 1
        EndIf
      EndIf
;;oooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo      
        If KeyboardReleased(#PB_Key_V) 
          MeshData(v)\y + 0.3:v+1
          If v=MeshVertexCount(#mesh, 0):v=0:EndIf
          SetMeshData(#mesh,0, MeshData(), #PB_Mesh_Vertex | #PB_Mesh_Normal, 0, MeshVertexCount(#mesh, 0)-1)
        
        EndIf
        If KeyboardPushed(#PB_Key_Up)
          KeyY = -#CameraSpeed
        ElseIf KeyboardPushed(#PB_Key_Down)
          KeyY = #CameraSpeed
        Else
          KeyY = 0
        EndIf
        
        If KeyboardPushed(#PB_Key_Left)
          KeyX = -#CameraSpeed
        ElseIf KeyboardPushed(#PB_Key_Right)
          KeyX = #CameraSpeed
        Else
          KeyX = 0
        EndIf
      EndIf
      If ExamineMouse()
        MouseX = -(MouseDeltaX()/10)
        MouseY = -(MouseDeltaY()/10)
      EndIf
      MoveCamera  (0, KeyX, 0, KeyY)
      RotateCamera(0,  MouseY, MouseX, 0, #PB_Relative) 
            
      ;RotateEntity(#cube, 0,1,0, #PB_Relative)
      RenderWorld()
      
      FlipBuffers()
    Until KeyboardPushed(#PB_Key_Escape) Or Quit = 1
    
Else
  MessageRequester("Error", "The 3D Engine can't be initialized", 0)
EndIf

End

PureBasic Forums - English

where is Mesh Triangle number 0 or 100 ??

where is Mesh Triangle number 0 or 100 ??