How to learn 3D modeling?

[flows-network-integration[bot]]

Here are some steps to learn 3D modeling:

1. Choose the software – 3D modeling applications vary in features and prices. You may want to research which software best suits your needs and budget.

2. Learn the basic principles – brush up on the fundamentals of 3D modeling, such as understanding shape and form, composition, and lighting principles.

3. Take a class – consider enrolling in an online or in-person course to learn the basics of 3D modeling from a professional instructor.

4. Experiment and practice – start creating simple models and continue learning as you create more complex ones. Experiment with different techniques and try different software programs.

5. Join a community – join online communities, forums, or social media groups related to 3D modeling to learn from other artists and receive feedback on your work.

6. Stay up-to-date – stay updated on the latest trends in 3D modeling to keep your skills fresh and relevant.

Remember, learning 3D modeling takes practice, patience, and persistence. Keep challenging yourself and continue to learn and grow in your skills.

[weili520]

Can you provide me with some free study materials?

[weili520]

Here are some steps to learn 3D modeling:

1. Choose the software – 3D modeling applications vary in features and prices. You may want to research which software best suits your needs and budget.
2. Learn the basic principles – brush up on the fundamentals of 3D modeling, such as understanding shape and form, composition, and lighting principles.
3. Take a class – consider enrolling in an online or in-person course to learn the basics of 3D modeling from a professional instructor.
4. Experiment and practice – start creating simple models and continue learning as you create more complex ones. Experiment with different techniques and try different software programs.
5. Join a community – join online communities, forums, or social media groups related to 3D modeling to learn from other artists and receive feedback on your work.
6. Stay up-to-date – stay updated on the latest trends in 3D modeling to keep your skills fresh and relevant.

Remember, learning 3D modeling takes practice, patience, and persistence. Keep challenging yourself and continue to learn and grow in your skills.

Hello ?

[flows-network-integration[bot]]

Hello! How can I assist you?

[weili520]

Can you provide me with some free study materials for learn it?

[flows-network-integration[bot]]

Sure! Here are some free resources you can use to study 3D modeling:

1. Blender Guru - Blender Guru is a popular YouTube channel that provides free Blender tutorials and courses for beginners and advanced users alike.

2. SketchUp - SketchUp offers a free version of its modeling software, as well as free tutorials and learning resources on its website.

3. Autodesk Education Community - Autodesk provides a free student version of many of its popular 3D modeling software applications, as well as tutorials and learning resources on its Education Community page.

4. 3D Buzz - 3D Buzz is a website that provides free video tutorials on a variety of 3D modeling topics, including software-specific tutorials.

5. CG Cookie - CG Cookie offers a free trial to its website, which features tutorials on a range of 3D modeling and animation topics.

6. Udemy - Udemy is an online learning platform that offers some free 3D modeling courses.

These are just a few options available for free 3D modeling study materials. There are many other websites and resources available online as well.

[weili520]

any more ?

[flows-network-integration[bot]]

Sure, here are some more free resources for learning 3D modeling:

7. YouTube - In addition to Blender Guru, there are many other YouTube channels that offer free tutorials and tips on 3D modeling, such as 3D Modeling for Beginners, PolyMatter, and Pierrick Picaut.

8. TurboSquid - TurboSquid offers free 3D models that you can use in your own projects or study to learn techniques for making your own models.

9. Tinkercad - Tinkercad is a free, browser-based 3D modeling tool that is designed for beginners.

10. Unity Learn - Unity is a popular game engine that offers free tutorials and courses on 3D modeling and game development.

11. 3DTotal - 3DTotal offers a range of free tutorials on 3D modeling, texturing, and rendering.

Ultimately, the best way to learn 3D modeling is through practice and experimentation, so don't be afraid to play around with different techniques and software programs as you learn. Good luck!

[itlemon]

Protobuf如何定义出map<string, List>类型？

[flows-network-integration[bot]]

在Protocol Buffer中定义map<string, List>类型，需要使用Map字段类型。该类型需要指定键的数据类型和值的数据类型。在这种情况下，键的数据类型是字符串，需要使用string类型，而值的数据类型是一个列表，并且该列表包含pojo类型的元素。因此，您可以使用repeated关键字来定义列表类型，并使用message关键字定义pojo类型。

下面是一个示例代码，定义了一个包含三个字段的message类型，其中包含Map字段类型：

message MyMessage {
  map<string, MyPojoList> myMap = 1;
}

message MyPojo {
  int32 id = 1;
  string name = 2;
}

message MyPojoList {
  repeated MyPojo myPojo = 1;
}

在这个例子中，MyMessage包含一个名为myMap的Map类型字段，其中键的类型为string，值的类型为MyPojoList。MyPojoList是另一个message类型，其中包含一个repeated字段类型，用于存储MyPojo类型的元素。

这是如何使用protobuf定义map<string, List>类型的方式。

[itlemon]

leetcode第33题用Java怎么解决？

[flows-network-integration[bot]]

LeetCode第33题是“搜索旋转排序数组”，给定一个经过旋转的升序数组，要求在该数组中搜索给定的目标值，并返回其索引。如果目标值不存在于数组中，返回-1。要求算法时间复杂度为$O(log n)$级别。

下面是一种Java的解法：

class Solution {
    public int search(int[] nums, int target) {
        int low = 0;
        int high = nums.length - 1;
        while (low <= high) {
            int mid = low + (high - low) / 2;
            if (nums[mid] == target) {
                return mid;
            } else if (nums[mid] >= nums[low]) {
                if (target >= nums[low] && target < nums[mid]) {
                    high = mid - 1;
                } else {
                    low = mid + 1;
                }
            } else {
                if (target <= nums[high] && target > nums[mid]) {
                    low = mid + 1;
                } else {
                    high = mid - 1;
                }
            }
        }
        return -1;
    }
}

该算法的思想是二分查找。首先，找到中间的数mid。如果nums[mid]等于目标值，就直接返回mid。否则，判断nums[mid]与nums[low]的大小关系。如果nums[mid]大于等于nums[low]，则说明mid之前的数都是大于等于nums[mid]的。这时，如果target在nums[low]和nums[mid]之间，那么说明target在mid之前，可以将搜索范围变为[low, mid-1]，否则搜索范围变为[mid+1, high]。

如果nums[mid]小于nums[low]，则说明mid之前的数不是严格单调递增的（因为在旋转点右侧，nums[mid]之前的数都比nums[low]要大），而mid之后的数是严格单调递增的。这时，如果target在nums[mid]和nums[high]之间，那么说明target在mid之后，可以将搜索范围变为[mid+1, high]，否则搜索范围变为[low, mid-1]。

通过不断缩小搜索范围，最终可以找到目标值的位置，或者返回-1表示目标值不存在于数组中。该算法的时间复杂度为$O(log n)$，空间复杂度为$O(1)$。

[itlemon]

如何将一个List形式的Json转换成List Protobuf形式？

[flows-network-integration[bot]]

我们可以采用以下步骤将一个List形式的Json转换成List Protobuf形式：

1. 首先，我们需要定义一个与Json数据结构对应的Protobuf消息类型。

例如，如果Json数据结构的形式为：

[{"id": 1, "name": "Alice"}, {"id": 2, "name": "Bob"}]

那么对应的Protobuf消息类型可能是：

message Person {
    int32 id = 1;
    string name = 2;
}

message PersonList {
    repeated Person persons = 1;
}

2. 然后，我们可以使用第三方库将Json数据解析成一个List形式。

假设我们使用的是Python，可以使用json模块：

import json

json_str = '[{"id": 1, "name": "Alice"}, {"id": 2, "name": "Bob"}]'
json_obj = json.loads(json_str)

3. 接下来，我们需要将解析出来的Json对象转换成Protobuf格式。

可以使用Protobuf的from_dict()方法，传入一个字典对象，并自动将其转换成Protobuf消息。

from google.protobuf.json_format import from_dict

person_list = from_dict({'persons': json_obj}, PersonList())

4. 最后，我们可以将Protobuf消息序列化成二进制格式，便于存储和传输。

person_list_byte = person_list.SerializeToString()