问题描述
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我正在尝试制作绕地球轨道运行的卫星的轨迹（海拔7000公里的圆形轨道）的动画。以下向量x，y，z表示参考系统中它的坐标（由于非球面重力势而对加速度进行积分）。
fh = figure(\'DoubleBuffer\',\'on\');
ah = axes(\'Parent\',fh,\'Units\',\'normalized\',\'Position\',[0 0 1 1],...
\'DataAspectRatio\',[1 1 1],\'DrawMode\',\'fast\');
x = 1.0e+003 * [ 1.293687086462776 1.355010603320554 ...
1.416226136451621 1.477328806662750 1.538313743926646...
1.841302933101510 2.140623861743577 2.435680048370655...
2.725883985836056 3.830393161542639 4.812047393962632...
5.639553477924236 6.285935904692739 6.778445814703028...
6.981534839226300 6.886918327688911 6.496619397538814...
5.886899070860056 5.061708852126299 4.051251943168882...
2.891621923700204 1.551975259009857 0.148687346809817...
-1.259946709379085 -2.614876359324573 -3.789635985368149...
-4.822735075152957 -5.675398819678173 -6.314344260262741...
-6.725008970265510 -6.860046738669579 -6.714044347581475...
-6.291232549137548 -5.646225528669501 -4.790489239458692...
-3.756316068441812 -2.581710448683235 -1.257064527234605...
0.118190083177733 1.488198207705392 2.797262268588749...
3.943218990855596 4.943060241667732 5.760107224604901...
6.363435161221018 6.741208871652011 6.844507242544970...
6.669637491855506 6.222229021788314 5.549112743364572...
4.665587166679964 3.605338508383659 2.407805301565781...
1.076891826523990 -0.297413079432155 -1.658804233546807...
-2.950960371016551 -4.105336427038419 -5.093651475630134...
-5.875676956725480 -6.417825276834068 -6.694317613708315...
-6.702354075060146 -6.441476385534835 -5.920328191821120...
-5.149356931765655 -4.165756794143557 -3.010476122311884...
-1.730623521107957 -0.547981318845428 0.651933236927557...
1.830754553013015 2.950797411065132];
y = 1.0e+003 *[ -6.879416537989226 -6.867600717396513...
-6.855237614338527 -6.842328214064634 -6.828873545169439...
-6.753459997528374 -6.664593892931937 -6.562452270514113...
-6.447238135027323 -5.857768973060929 -5.080802144227667...
-4.141502963266585 -3.069449548231363 -1.712593819793112...
-0.283073212084787 1.157789207734001 2.547934226666446...
3.733185664633135 4.781256997101091 5.653507474532885...
6.316540958291930 6.760480121739906 6.924451844039825...
6.801366712306432 6.393950562012035 5.763652137956600...
4.918852380803697 3.890903548710424 2.717191733101876...
1.385839187748386 -0.001786735280855 -1.388680800030854...
-2.717513794724399 -3.877348086956174 -4.892062889940518...
-5.723943344458780 -6.341064412332522 -6.729295147896739...
-6.844976271597333 -6.684181367561298 -6.252308741323985...
-5.600523241569850 -4.741636145151388 -3.707934368103928...
-2.537101251915556 -1.208445066639178 0.169057351189467...
1.539102816836380 2.845512534980855 3.993289528709769...
4.989150886098799 5.795183343929699 6.379362665363127...
6.723976759736427 6.794165677259719 6.586864956951024...
6.108394444576384 5.387403581100790 4.449452017586583...
3.332306147336086 2.080126804848620 0.757432563194591...
-0.595089763589023 -1.923045482863719 -3.172486599444496...
-4.302442851663575 -5.254127434062967 -5.988250483410006...
-6.472859710456819 -6.675113607083117 -6.664054266658221...
-6.440275312105615 -6.010308893159839];
z = [ -1.348762314964606 -1.416465504571016 -1.484053975854905...
-1.551522350691171 -1.618865254528658 -1.953510294130345...
-2.284215283426580 -2.610320163346533 -2.931177500785390...
-4.153679292291825 -5.242464339076090 -6.162825517200489...
-6.884797354552217 -7.440577139596716 -7.680358197465111...
-7.594616346122523 -7.183952381870657 -6.529293328494871...
-5.637062917332294 -4.540678277777376 -3.279180600545935...
-1.817413221203883 -0.280548741687378 1.268253040429052...
2.764251377698321 4.066975661566477 5.218214283582148...
6.174673504642019 6.899157495671121 7.375688520371054...
7.548875108319217 7.410793523141250 6.965068314483629...
6.271309946313485 5.343254095742233 4.215431448848456...
2.928028129903598 1.469574073877195 -0.048649548535536...
-1.563638474934283 -3.013536101911645 -4.285161526803897...
-5.397128342069014 -6.308837263463213 -6.985946890567337...
-7.415475222950275 -7.542406523585701 -7.363021555333582...
-6.884639818710263 -6.158276823110702 -5.199186592259776...
-4.043958234344444 -2.736923814690622 -1.283388986878655...
0.219908617803070 1.712828428793243 3.135072606759898...
4.411790351254605 5.510842969067953 6.387336537361380...
7.004133661144990 7.332163450286972 7.366696289243980...
7.105258174916579 6.555393588532904 5.727091807637045...
4.660073989309112 3.399622357708514 1.999243120787114...
0.701744421660999 -0.620073499615723 -1.923270654698332...
-3.164705887374677 ];
load(\'topo.mat\',\'topo\',\'topomap1\');
[x1,y1,z1] = sphere(50);
x1 = 6678.14*x1;
y1 = 6678.14*y1;
z1 = 6678.14*z1;
props.AmbientStrength = 0.1;
props.DiffuseStrength = 1;
props.specularColorReflectance = .5;
props.specularExponent = 20;
props.specularStrength = 1;
props.FaceColor= \'texture\';
props.EdgeColor = \'none\';
props.FaceLighting = \'phong\';
props.Cdata = topo;
surface(x1,z1,props);
light(\'position\',[-1 0 1]);
light(\'position\',[-1.5 0.5 -0.5],\'color\',[.6 .2 .2]);
view(3);
handles.p1 = line(\'parent\',ah,\'XData\',x(1),\'YData\',y(1),\'ZData\',...
z(1),\'Color\',\'red\',\'linewidth\',2);
handles.p2 = line(\'parent\',x(end),y(end),...
\'ZData\',z(end),\'Marker\',\'o\',\'MarkerSize\',6,\'MarkerFaceColor\',\'b\');
oaxes([0 0 0],\'Arrow\',\'extend\',\'AxisLabelLocation\',\'side\',...
\'Xcolor\',\'green\',\'Ycolor\',\'Zcolor\',\'green\');
axis vis3d equal;
handles.XLim = get(gca,\'XLim\');
handles.YLim = get(gca,\'YLim\');
handles.ZLim = get(gca,\'ZLim\');
set([handles.p1,handles.p2],\'Visible\',\'off\');
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(ah,\'XLim\',[xmin xmax],\'YLim\',[ymin ymax],\'Zlim\',[zmin zmax]);
view(3);
handles.hsat = line(\'parent\',z(1),\'b\');
k = uint8(2);
u2 = uint8(length(x));
while k<u2
handles.htray(k) = line([x(k-1) x(k)],[y(k-1) y(k)],[z(k-1) z(k)],...
\'Color\',3);
set(handles.hsat,x(k),y(k),z(k));
drawNow;
k = k + 1;
end
解决方法
这里有几件事。
DrawMode = fast可能不会按照您认为的那样做。它关闭了深度排序。我认为您真的想在这里进行深度排序。
您正在内部循环中创建线对象。您确实想要创建少量图形对象并重用它们。您是否可以创建单个线对象并在循环中设置XData，YData和ZData？
您可以使用hgtransform来避免修改hsat的坐标（如此处所述），但这只会在hsat更复杂的情况下有所作为。在这种情况下，我认为它不会为您带来任何好处。
您可以降低表面的分辨率。
您可能需要将图形的Renderer属性设置为OpenGL。
在这种情况下，但是使用您的代码，我的系统几乎每秒可以获取20帧。进行这些更改之后，我每秒获得大约100帧。您要在这里拍摄哪种帧率？
, 我相信动画慢的主要原因是因为您使用的Phong照明算法在计算上很昂贵。要查看其对性能的影响，请尝试指定Gouraud阴影：
%#lighting(\'gouraud\');
props.FaceLighting = \'gouraud\'; %# faster interpolating method