05网语文seo分析
1. 样条曲线的创建
在OpenCASCADE中，样条曲线（B样条曲线）是通过控制点来定义的。我们使用GeomAPI_PointsToBSpline类来根据给定的控制点生成B样条曲线。
TColgp_Array1OfPnt points(1, 4);
points.SetValue(1, gp_Pnt(-20, -20, 0));
points.SetValue(2, gp_Pnt(0, 30, 20));
points.SetValue(3, gp_Pnt(40, -20, 0));
points.SetValue(4, gp_Pnt(60, 30, 20));
GeomAPI_PointsToBSpline bsplineBuilder(points);
Handle(Geom_BSplineCurve) curve = bsplineBuilder.Curve();
TColgp_Array1OfPnt用于存储控制点。GeomAPI_PointsToBSpline根据控制点生成B样条曲线。curve是生成的B样条曲线对象。
2. 球体的创建
使用BRepPrimAPI_MakeSphere类创建一个球体。
BRepPrimAPI_MakeSphere makeSphere(3.0); // 半径为3
TopoDS_Shape sphere = makeSphere.Shape();
Handle(AIS_Shape) aisSphere = new AIS_Shape(sphere);
BRepPrimAPI_MakeSphere用于创建球体。sphere是球体的形状对象。aisSphere是用于显示球体的AIS_Shape对象。
3. 显示样条曲线和球体
将样条曲线和球体添加到视图中进行显示。
TopoDS_Edge edge = BRepBuilderAPI_MakeEdge(curve);
Handle(AIS_Shape) aisCurve = new AIS_Shape(edge);
context->Display(aisCurve, Standard_True);context->Display(aisSphere, Standard_True);
BRepBuilderAPI_MakeEdge将曲线转换为边。aisCurve是用于显示曲线的AIS_Shape对象。context->Display将对象添加到视图中显示。
4. 动画的实现
动画的核心是通过不断更新球体的位置来实现的。我们通过一个循环逐步改变球体在样条曲线上的位置。
void StartAnimation() {double uStart = curve->FirstParameter();double uEnd = curve->LastParameter();double t = 0.0;const double delta = 0.01;const int delayMs = 30;while (t <= 1.0) {MSG msg;while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {if (msg.message == WM_QUIT) {return;}TranslateMessage(&msg);DispatchMessage(&msg);}double u = uStart + t * (uEnd - uStart);gp_Pnt point;curve->D0(u, point);gp_Trsf trsf;trsf.SetTranslation(gp_Vec(point.X(), point.Y(), point.Z()));aisSphere->SetLocalTransformation(trsf);context->UpdateCurrentViewer();view->Redraw();std::this_thread::sleep_for(std::chrono::milliseconds(delayMs));t += delta;}
}
uStart和uEnd是样条曲线的参数范围。t是动画的参数，从0到1逐步增加。u是当前的曲线参数，根据t计算得到。curve->D0(u, point)计算曲线在参数u处的点point。gp_Trsf用于创建平移变换，将球体移动到point位置。aisSphere->SetLocalTransformation(trsf)更新球体的位置。context->UpdateCurrentViewer()和view->Redraw()更新视图并重绘。std::this_thread::sleep_for用于控制动画的速度。
5. 按钮点击事件
按钮点击事件触发动画函数StartAnimation。
LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {switch (msg) {case WM_COMMAND:if (LOWORD(wParam) == 1) { // 按钮点击事件StartAnimation();}break;case WM_DESTROY:PostQuitMessage(0);break;default:return DefWindowProcW(hwnd, msg, wParam, lParam);}return 0;
}
WM_COMMAND消息处理按钮点击事件。LOWORD(wParam) == 1判断点击的是哪个按钮。- 调用
StartAnimation函数开始动画。
6. 完整代码
#include <Windows.h>
#include <AIS_Shape.hxx>
#include <AIS_InteractiveContext.hxx>
#include <V3d_Viewer.hxx>
#include <V3d_View.hxx>
#include <OpenGl_GraphicDriver.hxx>
#include <WNT_Window.hxx>
#include <GeomAPI_PointsToBSpline.hxx>
#include <TColgp_Array1OfPnt.hxx>
#include <BRepPrimAPI_MakeSphere.hxx>
#include <BRepBuilderAPI_MakeEdge.hxx>
#include <gp_Pnt.hxx>
#include <gp_Trsf.hxx>
#include <TopoDS_Edge.hxx>
#include <Geom_BSplineCurve.hxx>
#include <chrono>
#include <thread>// 全局变量，用于存储OpenCASCADE对象
Handle(AIS_Shape) aisSphere;
Handle(Geom_BSplineCurve) curve;
Handle(V3d_View) view;
Handle(AIS_InteractiveContext) context;// 创建OpenCASCADE窗口
HWND CreateOCCWindow() {HINSTANCE hInstance = GetModuleHandle(NULL);WNDCLASSW wc = { 0 };wc.style = CS_HREDRAW | CS_VREDRAW;wc.lpfnWndProc = DefWindowProcW;wc.hInstance = hInstance;wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);wc.hCursor = LoadCursor(NULL, IDC_ARROW);wc.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);wc.lpszClassName = L"OCCWindowClass";RegisterClassW(&wc);HWND hwnd = CreateWindowW(L"OCCWindowClass",L"OpenCASCADE Animation",WS_OVERLAPPEDWINDOW,CW_USEDEFAULT, CW_USEDEFAULT, 1024, 768,NULL, NULL, hInstance, NULL);ShowWindow(hwnd, SW_SHOW);UpdateWindow(hwnd);return hwnd;
}// 动画函数
void StartAnimation() {double uStart = curve->FirstParameter();double uEnd = curve->LastParameter();double t = 0.0;const double delta = 0.01;const int delayMs = 30;while (t <= 1.0) {MSG msg;while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {if (msg.message == WM_QUIT) {return;}TranslateMessage(&msg);DispatchMessage(&msg);}double u = uStart + t * (uEnd - uStart);gp_Pnt point;curve->D0(u, point);gp_Trsf trsf;trsf.SetTranslation(gp_Vec(point.X(), point.Y(), point.Z()));aisSphere->SetLocalTransformation(trsf);context->UpdateCurrentViewer();view->Redraw();std::this_thread::sleep_for(std::chrono::milliseconds(delayMs));t += delta;}
}LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {switch (msg) {case WM_COMMAND:if (LOWORD(wParam) == 1) { // 按钮点击事件// 调用动画函数StartAnimation();}break;case WM_DESTROY:PostQuitMessage(0);break;default:return DefWindowProcW(hwnd, msg, wParam, lParam);}return 0;
}int main() {// 创建窗口HWND hwnd = CreateOCCWindow();// 创建按钮CreateWindowW(L"BUTTON",L"Start Animation",WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_PUSHBUTTON,10, 10, 100, 30,hwnd,(HMENU)1,NULL,NULL);// 设置窗口过程SetWindowLongPtrW(hwnd, GWLP_WNDPROC, (LONG_PTR)WndProc);Handle(WNT_Window) window = new WNT_Window(hwnd);// 初始化图形驱动Handle(OpenGl_GraphicDriver) graphicDriver = new OpenGl_GraphicDriver(new Aspect_DisplayConnection());// 创建ViewerHandle(V3d_Viewer) viewer = new V3d_Viewer(graphicDriver);viewer->SetDefaultLights();viewer->SetLightOn();// 创建ViewHandle(V3d_View) view_temp = viewer->CreateView();view_temp->SetWindow(window);view_temp->TriedronDisplay(Aspect_TOTP_LEFT_LOWER, Quantity_NOC_GOLD, 0.08, V3d_WIREFRAME);view_temp->SetBackgroundColor(Quantity_NOC_BLACK);view_temp->MustBeResized();view_temp->Redraw();// 创建InteractiveContextHandle(AIS_InteractiveContext) context_temp = new AIS_InteractiveContext(viewer);context_temp->SetDisplayMode(AIS_Shaded, Standard_True);// 创建样条曲线TColgp_Array1OfPnt points(1, 4);points.SetValue(1, gp_Pnt(-20, -20, 0));points.SetValue(2, gp_Pnt(0, 30, 20));points.SetValue(3, gp_Pnt(40, -20, 0));points.SetValue(4, gp_Pnt(60, 30, 20));GeomAPI_PointsToBSpline bsplineBuilder(points);Handle(Geom_BSplineCurve) curve_temp = bsplineBuilder.Curve();// 创建曲线Edge并显示TopoDS_Edge edge = BRepBuilderAPI_MakeEdge(curve_temp);Handle(AIS_Shape) aisCurve = new AIS_Shape(edge);context_temp->Display(aisCurve, Standard_True);// 创建球体BRepPrimAPI_MakeSphere makeSphere(3.0);TopoDS_Shape sphere = makeSphere.Shape();Handle(AIS_Shape) aisSphere_temp = new AIS_Shape(sphere);context_temp->Display(aisSphere_temp, Standard_True);// 调整视图以适应内容view_temp->FitAll();// 将全局变量赋值aisSphere = aisSphere_temp;curve = curve_temp;view = view_temp;context = context_temp;// 保持窗口打开，直到用户关闭MSG msg;while (GetMessage(&msg, NULL, 0, 0)) {TranslateMessage(&msg);DispatchMessage(&msg);}return 0;
}
