Matlab实时绘制3D圆柱图问题求助：自定义colormap失效、实时编辑器不显示

根因与对应修正点 #

• 每次弹出新figure窗口：原代码在for循环内部调用了figure，每次循环都会创建新画布，将figure挪到循环外，且循环内不重复创建surf对象，仅更新其数据属性即可，还可大幅提升更新流畅度。
• 自定义colormap失效：原代码硬编码了colormap('parula')，直接覆盖了加载的自定义色卡，将该参数替换为mat文件中存储的色卡变量名即可。
• 实时编辑器无法显示：实时编辑器对频繁新建图形对象的支持较差，统一提前定义所有静态绘图属性（轴范围、光照、色轴范围等），循环内仅修改已有surf对象的属性，即可正常在实时编辑器内嵌入显示。
• 隐藏bug修正：原代码中tsize = size(T)返回的是二维向量，直接作为循环上限会导致循环次数异常，修正为tsize = size(T,1)直接取表格行数；同时原主程序调用的getHeatMap和实际定义的函数名getCylinderHeatMap不一致，已统一。

修正后完整代码 #

主程序 #

clc;
clear all;
close all;

filename = ['*The file pathway*' 'filenames.txt'];
T = readtable(filename);
tsize = size(T,1);

% 提前加载自定义色卡
load('newColorMap.mat');
% 提前创建画布、固定所有静态绘图属性
fig = figure();
ax = axes(fig);
axis(ax,[0 400 -200 200 -200 200])
colorbar(ax)
colormap(ax, newColorMap) % 若mat文件内色卡变量名不同，替换为实际变量名即可
lighting(ax,'gouraud')
camlight(ax)
material(ax,'dull')
caxis(ax,[0 80])
hold(ax,'on')

% 预创建surf对象
filename = strcat('*The file pathway*', string(T{1,1}));
heat = double(getCylinderHeatMap(filename));
[X,tY] = meshgrid( linspace(1,400,size(heat,2)),linspace(0,2*pi,size(heat,1)));
max_heat = max(heat, [], 'all');
min_heat = min(heat, [], 'all');
R = (((heat-min_heat)/(max_heat-min_heat))*50)+100;
Y = cos(tY) .* R;
Z = sin(tY) .* R;
[nx, ny, nz] = surfnorm(X,Y,Z);
nv = reshape([nx ny nz], size(nx,1),size(nx,2),3);
s = surf(ax,X,Y,Z,heat,'VertexNormals',nv, 'EdgeColor','none');

% 循环更新帧
for i = 2:tsize
    filename = strcat('*The file pathway*', string(T{i,1}));
    heat = double(getCylinderHeatMap(filename));
    [X,tY] = meshgrid( linspace(1,400,size(heat,2)),linspace(0,2*pi,size(heat,1)));
    max_heat = max(heat, [], 'all');
    min_heat = min(heat, [], 'all');
    R = (((heat-min_heat)/(max_heat-min_heat))*50)+100;
    Y = cos(tY) .* R;
    Z = sin(tY) .* R;
    [nx, ny, nz] = surfnorm(X,Y,Z);
    nv = reshape([nx ny nz], size(nx,1),size(nx,2),3);
    % 仅更新surf的数据属性，不新建对象
    s.XData = X;
    s.YData = Y;
    s.ZData = Z;
    s.CData = heat;
    s.VertexNormals = nv;
    drawnow limitrate % 加limitrate避免卡顿，若需要控制速度可加pause(0.1)调整停留时长
end

getCylinderHeatMap函数 #

function heat = getCylinderHeatMap(filename)
    s = dir(filename);
    fin = fopen(filename,'r');
    I=fread(fin,s.bytes,'uint8=>uint8');
    
    w = uint16(I(1))+256*uint16(I(2));
    h = uint16(I(3))+256*uint16(I(4));
    skip = s.bytes - w*h + 1;
    IN = I(skip:1:s.bytes);
    Z=single(reshape(IN,w,h));
    Z=griddedInterpolant(Z');
    y_range = linspace(1.0,single(h),360);
    x_range = linspace(1.0,single(w),512);
    heat = uint8(Z({y_range, x_range}));
end

额外注意事项 #

如果加载newColorMap.mat后色卡仍然无法正常显示，可在加载语句后运行who命令查看mat文件导出的变量名，替换代码中colormap调用的参数即可。

内容的提问来源于stack exchange，提问作者Codexing