Question

以下代码是地球地球向东旋转的图形渲染。我有两个按钮，旋转和停止。两者共享相同的回调函数hAnimaCallback。特别是后者不起作用。我假装使用按钮的字符串（名称）来创建一个停止移动的开关。但是，我无法更改while循环中的字符串名称，我不明白为什么我的方法是错误的。

function example
fh = figure('Menu','none','Toolbar','none','Units','characters');
T = 0:pi/100:2*pi;
Y = zeros(numel(T),3);
Y(:,1) = 7000*cos(T);
Y(:,2) = 7000*sin(T);
hPanAni = uipanel('parent',fh,'Units','characters','Position',...
    [22.6 10.4 53 23],'title','Controls','FontSize',11,...
    'FontAngle','italic','FontWeight','bold');
hIniAni = uicontrol(hPanAni,'Style','pushbutton','Units','normalized',...
    'Position',[0.14 0.64 0.5 0.12],'String','Spin',...
    'FontSize',10,'Callback',@hAnimaCallback);
hFinAni = uicontrol(hPanAni,'Style','pushbutton','Units','normalized',...
    'Position',[0.14 0.26 0.5 0.12],'String','Stop',...
    'FontSize',10,'Callback',@hAnimaCallback);
hPantSim = uipanel('Parent',fh,'Units','characters',...
    'Position',[107.87 8 157.447 42],'BorderType','none','title',...
    'Screen','FontSize',11,'FontAngle','italic',...
    'FontWeight','bold');
hPantSimInt = uipanel('Parent',hPantSim,'Units','normalized','Position',...
    [0 0 1 1],'BorderType','line','BackgroundColor','black');
ah4 = axes('Parent',hPantSimInt,'Units','normalized','Position',...
    [0 0 1 1],'Color','none','Visible','off','DataAspectRatio',...
    [1 1 1],'NextPlot','add');
rotate3d(ah4);
hgrot = hgtransform('Parent',ah4);
Resf = 6378;
maptext = imread('tierra.jpg');
[X, map] = rgb2ind(maptext,128);
[x,y,z] = sphere(50);
x = Resf*x;
y = Resf*y;
z = Resf*z;
props.FaceColor= 'texture';
props.EdgeColor = 'none';
props.Parent = hgrot;
props.Cdata = flipud(X); % it is necesary to do this for getting the 
% appropiate image on the sphere
hsurf = surface(x,y,z,props);
colormap(map);
axis equal;
view([71 14]);
set(gcf,'Renderer','opengl')
drawnow;
line('parent',ah4,'XData',Y(:,1),'YData',Y(:,2),'ZData',...
    Y(:,3),'Color','red','LineWidth',2);
line('parent',ah4,'XData',Y(end,1),'YData',Y(end,2),...
    'ZData',Y(end,3),'Marker','o','MarkerSize',6,'MarkerFaceColor','b');
axis square equal vis3d;
view(3);
handles.XLim = get(ah4,'XLim');
handles.YLim = get(ah4,'YLim');
handles.ZLim = get(ah4,'ZLim');
xmin = handles.XLim(1);
ymin = handles.YLim(1);
zmin = handles.ZLim(1);
xmax = handles.XLim(2);
ymax = handles.YLim(2);
zmax = handles.ZLim(2);
set(ah4, 'XLim', [xmin xmax],'YLim', [ymin ymax],'Zlim',[zmin zmax]);
az = 0;
    function hAnimaCallback(hObject,evt)
        while (ishandle(fh))
            state = get(hObject,'String'), % state should change between the states of
            % Spin and Stop but this does not occur
            if (strcmp(state,'Stop'))
              break;
            else
              az = az + 0.01745329252;
              set(hgrot,'Matrix',makehgtform('zrotate',az));
              drawnow;  
            end  
        end
    end    
end

Answer 1

由于drawnow循环中重复的while调用，您似乎遇到了某种竞争状态。当您按下“停止”按钮时，状态将更改为“停止”，但需要快速注意。基本上，while循环的运行速度与MATLAB可以运行的速度一样快。而不是drawnow使用pause(0.1)命令似乎工作（稍微改变代码逻辑）：

az = 0;
spin = false;
  function hAnimaCallback(hObject,~)
    state = get(hObject,'String')
    if strcmp(state, 'Spin')
      spin = true;
    else
      spin = false;
    end

    while (spin)
      az = az + 0.01745329252;
      set(hgrot,'Matrix',makehgtform('zrotate',az));
      pause(0.1);
    end
  end

更新回调内的字符串

1 个答案: