{"topic":{"id":7251,"title":"关于各向同性重网格化的效果","slug":"topic","categoryId":56,"createdAt":"2023-11-15 08:55:44.17219","bumpedAt":"2023-11-16 14:47:29.654774","views":230,"postsCount":5,"highestPostNumber":5,"likeCount":0,"closed":true,"pinned":false,"pinnedGlobally":false,"pinnedAt":null,"pinnedUntil":null,"isBanner":false,"excerpt":"我完成了重网格化的 split、flip 和 average 的部分，能够正常合理地运行但当我把 collapse 部分的代码加上之后，能够成功运行，但效果很差下图是我分别处理了三次，我的牛牛的犄角变得很不规则，而且牛牛的脸也写满了沧桑 😢 想问问这样的效果能拿到 remesh 里面 collapse 的 10 分吗 😭","deletedAt":null,"isAnonymous":false,"category":{"id":56,"name":"计算机图形学","slug":"cg","color":"92278F"},"author":{"id":266,"username":"XLX","name":"阿斯巴甜（含苯丙氨酸）","avatarUrl":"/uploads/image/c9/1a/c91af37bee86401b024d7eff71f823111cb6819a3217acfb6547a5aa34d82e28.avif"},"tags":[]},"posts":[{"id":17151,"postNumber":1,"raw":"我完成了重网格化的 split、flip 和 average 的部分，能够正常合理地运行\n但当我把 collapse 部分的代码加上之后，能够成功运行，但效果很差\n下图是我分别处理了三次，我的牛牛的犄角变得很不规则，而且牛牛的脸也写满了沧桑 :cry:\n[grid mode=\"tile\"]\n![remeshing|690x377](/uploads/image/b5/33/b53372d68a6e5c31c89839ccad4da1b9be54f5ee897505a8b4a22aecce27ac8c.avif)\n![remeshing0|690x377](/uploads/image/cf/42/cf4224aff29ba88b9ed9393fa9fa225f1e69692d56066d5b9796f7e2f8db1a60.avif)\n![remeshing1|690x378](/uploads/image/e5/60/e560aaf9f751782e3fd6a23c4694838e54bc340724640f881f72649df5e2ba2f.avif)\n[/grid]\n\n想问问这样的效果能拿到 remesh 里面 collapse 的 10 分吗 :loudly_crying_face:","cooked":"

我完成了重网格化的 split、flip 和 average 的部分，能够正常合理地运行
\n但当我把 collapse 部分的代码加上之后，能够成功运行，但效果很差
\n下图是我分别处理了三次，我的牛牛的犄角变得很不规则，而且牛牛的脸也写满了沧桑 😢

$\"remeshing\"$
\n $\"remeshing0\"$
\n $\"remeshing1\"$

想问问这样的效果能拿到 remesh 里面 collapse 的 10 分吗 😭

\n","createdAt":"2023-11-15 08:55:44.26385","updatedAt":"2023-11-15 15:46:50.871474","replyToPostNumber":null,"replyCount":0,"likeCount":0,"wordCount":117,"liked":false,"bookmarked":false,"polls":[],"reactions":[],"wiki":false,"version":2,"publicVersion":2,"deletedAt":null,"isAnonymous":false,"user":{"id":266,"username":"XLX","name":"阿斯巴甜（含苯丙氨酸）","avatarUrl":"/uploads/image/c9/1a/c91af37bee86401b024d7eff71f823111cb6819a3217acfb6547a5aa34d82e28.avif","admin":false,"moderator":false,"signatureRaw":null,"signatureCooked":null}},{"id":17152,"postNumber":2,"raw":"突然想到是不是先 flip 后 collapse 会好一点 :thinking:\n这样是不是可以避免最后一轮 iteration 后剩下很多狭长的三角形\n但是牛角那个地方总是会出现尖锐的三角锥，很难受（\n\n提前感谢助教学长和路过的大佬相助 :folded_hands:","cooked":"

突然想到是不是先 flip 后 collapse 会好一点 🤔
\n这样是不是可以避免最后一轮 iteration 后剩下很多狭长的三角形
\n但是牛角那个地方总是会出现尖锐的三角锥，很难受（

提前感谢助教学长和路过的大佬相助 🙏

\n","createdAt":"2023-11-15 09:00:39.237815","updatedAt":"2023-11-15 09:00:39.237815","replyToPostNumber":null,"replyCount":0,"likeCount":0,"wordCount":82,"liked":false,"bookmarked":false,"polls":[],"reactions":[],"wiki":false,"version":1,"publicVersion":1,"deletedAt":null,"isAnonymous":false,"user":{"id":266,"username":"XLX","name":"阿斯巴甜（含苯丙氨酸）","avatarUrl":"/uploads/image/c9/1a/c91af37bee86401b024d7eff71f823111cb6819a3217acfb6547a5aa34d82e28.avif","admin":false,"moderator":false,"signatureRaw":null,"signatureCooked":null}},{"id":17153,"postNumber":3,"raw":"![remeshing2|690x378](/uploads/image/8e/6a/8e6a9853a88a922d771e08a4b23760143330d5b0f7c28a67b896643b4920e882.avif)\n\n把 flip 放在 collapse 前面，感觉确实好点了","cooked":"

$\"remeshing2\"$

把 flip 放在 collapse 前面，感觉确实好点了

\n","createdAt":"2023-11-15 09:03:54.607568","updatedAt":"2023-11-15 09:03:54.607568","replyToPostNumber":null,"replyCount":0,"likeCount":0,"wordCount":16,"liked":false,"bookmarked":false,"polls":[],"reactions":[],"wiki":false,"version":1,"publicVersion":1,"deletedAt":null,"isAnonymous":false,"user":{"id":266,"username":"XLX","name":"阿斯巴甜（含苯丙氨酸）","avatarUrl":"/uploads/image/c9/1a/c91af37bee86401b024d7eff71f823111cb6819a3217acfb6547a5aa34d82e28.avif","admin":false,"moderator":false,"signatureRaw":null,"signatureCooked":null}},{"id":17199,"postNumber":4,"raw":"你最新的结果依然有些问题，有些部分的三角形显得过于尖锐了：（例如下图中蓝色方框标出的位置）\n\n![remeshing2|690x378](/uploads/image/ec/c6/ecc6c84908475d7ddae1e1fd803a4c02c0d1ccbfe31b23791268d5bf21754ed0.avif)\n\n正常来说，由于 *cow.dae* 这个 mesh 上的三角形分布已经比较均匀了，执行一次 remeshing 后的结果应该也是比较均匀的。这是参考实现的效果：（会出现几个狭长的三角形，但不会集中出现）\n\n![Screenshot_20231115_234313|633x500](/uploads/image/90/6a/906ae5e2f8f5a2204e79e27f800978fd26dac55a8654384ea4892cfdf505eb80.avif)\n\n而且虽然这个 mesh 的面数不太多，但它的形状比较圆润，没有什么特别尖锐的地方，所以执行 remeshing 后不太会出现棱角、缩小的现象。至少我用参考实现连续执行 4 次 remeshing 后，并没有观察到明显的收缩或棱角：\n\n![Screenshot_20231115_235324|633x500](/uploads/image/4b/a1/4ba174346049b3a7aa79dc277671be2d5f30956aa0e955be86671850e66c2c50.avif)\n\n我对你这种情况有两种猜想：splitting / collapsing 时没处理好，然后 flipping 导致没处理好的部位发生了凹陷；或者只是 smoothing 这一步没写对，导致被平滑的顶点有法线方向的移动。你可以检查一下自己的平滑操作是否写对了，如果感到平滑操作的任何说明有歧义，请在这个话题下继续补充疑问，我会尽量解释。","cooked":"

你最新的结果依然有些问题，有些部分的三角形显得过于尖锐了：（例如下图中蓝色方框标出的位置）

$\"remeshing2\"$

正常来说，由于 cow.dae 这个 mesh 上的三角形分布已经比较均匀了，执行一次 remeshing 后的结果应该也是比较均匀的。这是参考实现的效果：（会出现几个狭长的三角形，但不会集中出现）

$\"Screenshot_20231115_234313\"$

而且虽然这个 mesh 的面数不太多，但它的形状比较圆润，没有什么特别尖锐的地方，所以执行 remeshing 后不太会出现棱角、缩小的现象。至少我用参考实现连续执行 4 次 remeshing 后，并没有观察到明显的收缩或棱角：

$\"Screenshot_20231115_235324\"$

我对你这种情况有两种猜想：splitting / collapsing 时没处理好，然后 flipping 导致没处理好的部位发生了凹陷；或者只是 smoothing 这一步没写对，导致被平滑的顶点有法线方向的移动。你可以检查一下自己的平滑操作是否写对了，如果感到平滑操作的任何说明有歧义，请在这个话题下继续补充疑问，我会尽量解释。

\n","createdAt":"2023-11-15 15:58:08.489101","updatedAt":"2023-11-15 15:58:08.489101","replyToPostNumber":null,"replyCount":0,"likeCount":0,"wordCount":336,"liked":false,"bookmarked":false,"polls":[],"reactions":[],"wiki":false,"version":1,"publicVersion":1,"deletedAt":null,"isAnonymous":false,"user":{"id":1381,"username":"greyishsong","name":"greyishsong","avatarUrl":"/uploads/image/da/bc/dabc731b0311f59850625bbeb55ed969fcfac0430c5ef0f68441e5466b7aa496.avif","admin":false,"moderator":true,"signatureRaw":null,"signatureCooked":null}},{"id":17281,"postNumber":5,"raw":"![remeshdone|690x371](/uploads/image/df/68/df68c93ac4ffe648de1bded5a4c17264acc3038b4b3a2b14f97794e04deb4978.avif)\n感觉这个效果差不多了，谢谢助教学长！ :smiling_face_with_3_hearts:\n原来是之前对代码不熟悉的时候把 collapse 的 v_new 的位置理解错了，搞成 v_3 和 v_4 的中点了 :sweat_drops:","cooked":"

$\"remeshdone\"$
\n感觉这个效果差不多了，谢谢助教学长！ 🥰
\n原来是之前对代码不熟悉的时候把 collapse 的 v_new 的位置理解错了，搞成 v_3 和 v_4 的中点了 💦

\n","createdAt":"2023-11-16 14:47:29.654774","updatedAt":"2023-11-16 14:47:29.654774","replyToPostNumber":null,"replyCount":0,"likeCount":0,"wordCount":56,"liked":false,"bookmarked":false,"polls":[],"reactions":[],"wiki":false,"version":1,"publicVersion":1,"deletedAt":null,"isAnonymous":false,"user":{"id":266,"username":"XLX","name":"阿斯巴甜（含苯丙氨酸）","avatarUrl":"/uploads/image/c9/1a/c91af37bee86401b024d7eff71f823111cb6819a3217acfb6547a5aa34d82e28.avif","admin":false,"moderator":false,"signatureRaw":null,"signatureCooked":null}}],"hasMore":false,"lastReadPostNumber":1,"hasUrlPostNumber":false}