50行代码实现动图&交互

clear; clc; clf;

% ------------------- 设置 ------------------------------------------ %

set(gcf,'units', 'normal','position', [.1 .1 .8 .8],...   % figure属性                          

  'KeyPressFcn',@controls,   'color', [.6 .6 .8]);        % 绑定按键回调                             

set(gca,'color',  'black','position', [.05 .05 .9 .9],... % 坐标轴属性

         'XLim', [-5 100],    'YLim', [-5 100],...

        'XTick',       [],   'YTick', [],'nextplot',  'add')

             

global blockPos; blockPos = 0;                            % 底部方块                                                                         

blockVertices = @(x) [x-5,-2; x+5,-2; x+5, 0; x-5, 0];                     

blockObj = patch('Vertices', blockVertices(blockPos),...

                    'Faces', [1 2 3 4],'FaceColor', [.6 .8 .6]);

       

ballPos  = [ 10; 10];                                     % 小球            

ballVel  = [ .5;  1];                               

ballObj  = plot(ballPos(1),ballPos(2),'.',...

              'MarkerSize',50,'color',[.8 .6 .6]);        

% ----------------------- 主循环 ------------------------------------ %        

while 0 < 1                                              

    tic;                                                  % 开始计时

    

    if ballPos(1) > 100 || ballPos(1) < 0                 

        ballVel(1) = -ballVel(1);                         % 边界

    elseif ballPos(2) > 100

        ballVel(2) = -ballVel(2);                         % 顶部墙

    elseif ballPos(2) < 0 

        if abs(blockPos - ballPos(1)) < 5                 % 底部方块

            ballVel(2) = -ballVel(2);

        else                                              % 方块没接住球

            close all; break;                              

        end

    end 

    

    ballPos = ballPos + ballVel;                          % 球的动作         

    set(ballObj,'XData',ballPos(1),'YData',ballPos(2));

    set(blockObj,'Vertices',  blockVertices(blockPos));   

    pause(1/60 - toc);                                    % 60 fps

end

% -------------------- 回调函数 ------------------------------------ %

function controls(~, event)                               % 按键回调

    global blockPos                             

    switch event.Key

        case 'leftarrow'

            blockPos = blockPos - 5;            

        case 'rightarrow'

            blockPos = blockPos + 5;     

    end

end