今度は plot3d
で円柱(N角柱)を作成してみます。円柱の基本配置は、底面の中心が原点と一致し、軸が z 軸と平行であるような配置とします。基本配置の円柱を作成するScilabスクリプトをコード1に、このスクリプトによる描画の結果を図1にそれぞれ示します。
// make_cylinder_special.sce clear; xdel(winsid()); exec('genpat.sci', -1); // Cylinder spec Radius = 0.1; Height = 0.3; SideCount = 20; // Vertices vertices = zeros(2*SideCount, 3); for i = 1:SideCount theta = 2*%pi/SideCount*(i-1); vertices(i,:) = [Radius*cos(theta), Radius*sin(theta), 0]; vertices(SideCount+i,:) = [Radius*cos(theta), Radius*sin(theta), Height]; end // Side faces sideFaces = zeros(SideCount, 4); for i = 1:(SideCount-1) sideFaces(i,:) = [i, i+1, SideCount+i+1, SideCount+i]; end sideFaces(SideCount,:) = [SideCount, 1, SideCount+1, 2*SideCount]; // Bottom faces bottomFaces = [ 1:SideCount; (SideCount+1):2*SideCount]; // Side patches sidePatches = genpat(vertices, sideFaces); // Bottom patches bottomPatches = genpat(vertices, bottomFaces); // Draw patches h_fig = figure; h_fig.background = 8; h_sidePat = plot3d(sidePatches.x, sidePatches.y, sidePatches.z); h_sidePat.color_mode = 4; h_sidePat.foreground = 1; h_sidePat.hiddencolor = 4; h_bottomPat = plot3d(bottomPatches.x, bottomPatches.y, bottomPatches.z); h_bottomPat.color_mode = 4; h_bottomPat.foreground = 1; h_bottomPat.hiddencolor = 4; // Axes settings xlabel("x"); ylabel("y"); zlabel("z"); h_axes = gca(); h_axes.isoview = "on"; h_axes.box = "off"; h_axes.rotation_angles = [63.5, -127]; h_axes.data_bounds = [-0.2, -0.2, 0; 0.2, 0.2, 0.4]; xgrid;