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Wed, 06/10/2020 - 05:09
Hello,
i have read the source code of vuserdraw command in ViewerTest_OpenGlCommands.cxx. I want to draw something using the Render() function, which means i need to create a OpenGl_Workspace as the parameter of the Render() function. So i create a OpenGl_Workspace using a WNT_Window which is created by a dialog item in MFC. The problem is that i cannot see the view while the program runs successfully. Here is my code.
//create a window in a Dialog
CWnd* cpwnd = GetDlgItem(IDC_STATIC_CP);
Handle(WNT_Window) cp_wnt_wnd = new WNT_Window(cpwnd->m_hWnd);
//create a OpenGl_Workspace
Handle(OpenGl_GraphicDriver) myglGraphicDriver = theApp.GetGraphicDriver();
Handle(OpenGl_Window) myglWindow = myglGraphicDriver->CreateRenderWindow(cp_wnt_wnd, (Aspect_RenderingContext)0);
Handle(OpenGl_Caps) myglCaps = &myglGraphicDriver->ChangeOptions();
Handle(Graphic3d_StructureManager) myG3dStructureCanager = new Graphic3d_StructureManager(myglGraphicDriver);
OpenGl_StateCounter* myglStateCounter = new OpenGl_StateCounter();
Handle(OpenGl_View) myglView = new OpenGl_View(myG3dStructureCanager, myglGraphicDriver, myglCaps, myglStateCounter);
Handle(OpenGl_Workspace) myglWorkSpace = new OpenGl_Workspace(myglView, myglWindow);
// the code below is the same as the code in Render().
Handle(OpenGl_Context) myglContext myglContext = myglWorkSpace->GetGlContext();
const OpenGl_AspectMarker* aMA = myglWorkSpace->AspectMarker();
aMA->Aspect()->Type();
const OpenGl_AspectText* aTA = myglWorkSpace->AspectText();
aTA->Aspect()->Font();
OpenGl_Vec4 aColor=myglWorkSpace->LineColor();
myglContext->ShaderManager()->BindLineProgram(Handle(OpenGl_TextureSet)(), Aspect_TOL_SOLID, Graphic3d_TOSM_UNLIT, Graphic3d_AlphaMode_Opaque, false, Handle(OpenGl_ShaderProgram)());
myglContext->SetColor4fv(aColor);
const OpenGl_Vec3 aVertArray[4] =
{
OpenGl_Vec3(-10.0,-20.0,-30.0),
OpenGl_Vec3(10.0, 20.0, -30.0),
OpenGl_Vec3(10.0, 20.0, 30.0),
OpenGl_Vec3(-10.0,-20.0,30.0),
};
Handle(OpenGl_VertexBuffer) aVertBuffer = new OpenGl_VertexBuffer();
aVertBuffer->Init(myglContext, 3, 4, aVertArray[0].GetData());
aVertBuffer->BindAttribute(myglContext, Graphic3d_TOA_POS);
glDrawArrays(GL_LINE_LOOP, 0, aVertBuffer->GetElemsNb());
aVertBuffer->UnbindAttribute(myglContext, Graphic3d_TOA_POS);
aVertBuffer->Release(myglContext.get());
Thanks in advance.
Fri, 06/12/2020 - 12:20
OpenGl_Window is a low-level interface. It is supposed to be created by V3d_View/V3d_Viewer, not manually.
Fri, 06/12/2020 - 17:04
Then how can i get the OpenGl_Window created by a V3d_View/V3d_Viewer?
I want to create a OpenGl_Workspace so that i can use the opengl commands to render just like the vuserdraw.
Thank you for your reply.
Fri, 06/12/2020 - 17:29
V3d_View::Redraw() does a lot more things than just calling OpenGl_Element::Render().
Either, follow suggested rendered path (like in case of vuserdraw, which creates a custom AIS_InteractiveObject and OpenGl_Element), or you have to dig deep into TKOpenGl, TKV3d, TKService classes to see how they work.