我无法在 Eclipse 中设置 FLTK。我正在尝试使用以下代码(我在此处找到)创建一个 OpenGL 窗口:
#include <FL/Fl.H>
#include <FL/Fl_Gl_Window.H>
#include <FL/gl.h>
//
// Simple resizable 2D GL window
// erco 10/08/05
//
class MyGlWindow : public Fl_Gl_Window {
// DRAW METHOD
// OpenGL window: (w,h) is upper right, (-w,-h) is lower left, (0,0) is center
//
void draw() {
// First time? init viewport, etc.
if (!valid()) {
valid(1);
glLoadIdentity();
glViewport(0,0,w(),h());
glOrtho(-w(),w(),-h(),h(),-1,1);
}
// Clear screen
glClear(GL_COLOR_BUFFER_BIT);
// Draw white 'X'
glColor3f(1.0, 1.0, 1.0);
glBegin(GL_LINE_STRIP); glVertex2f(w(), h()); glVertex2f(-w(),-h()); glEnd();
glBegin(GL_LINE_STRIP); glVertex2f(w(),-h()); glVertex2f(-w(), h()); glEnd();
}
// HANDLE WINDOW RESIZING
// If window reshaped, need to readjust viewport/ortho
//
void resize(int X,int Y,int W,int H) {
Fl_Gl_Window::resize(X,Y,W,H);
glLoadIdentity();
glViewport(0,0,W,H);
glOrtho(-W,W,-H,H,-1,1);
redraw();
}
public:
// CONSTRUCTOR
MyGlWindow(int X,int Y,int W,int H,const char*L=0) : Fl_Gl_Window(X,Y,W,H,L) {
}
};
// MAIN
int main() {
Fl_Window win( 500, 300);
MyGlWindow mygl(10, 10, win.w()-20, win.h()-20);
win.resizable(mygl);
win.show();
return(Fl::run());
}
以下是发出的命令:
make -k all
Building file: ../main.cpp
Invoking: GCC C++ Compiler
g++ -I/usr/include/FL -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"main.d" -MT"main.d" -o"main.o" "../main.cpp"
Finished building: ../main.cpp
Building target: Experiment01
Invoking: GCC C++ Linker
g++ -L/usr/lib -o"Experiment01" ./main.o -lGL -lfltk
以下是错误:
/usr/include/FL/Fl_Gl_Window.H undefined reference to `Fl_Gl_Window::init()'
/usr/include/FL/Fl_Gl_Window.H undefined reference to `vtable for Fl_Gl_Window'
undefined reference to `Fl_Gl_Window::~Fl_Gl_Window()'
undefined reference to `Fl_Gl_Window::resize(int, int, int, int)'
我还需要链接什么?我试过-llibfltk.so -llibfltk_gl.so等,但总是说找不到指定的库。