glm返回nan进行简单翻译 [英] glm returning nan on simple translate

问题描述

我正在使用glfw，glad和glm修改OpenGL.在我正在使用的教程之一中，他们演示了glm的一些简单用法:

I'm tinkering with OpenGL using glfw, glad, and glm. In one of the tutorials I'm using, they demonstrate some simple usage of glm as so:

glm::vec4 vec(1.0f, 0.0f, 0.0f, 1.0f);
glm::mat4 trans;
trans = glm::translate(trans, glm::vec3(1.0f, 1.0f, 0.0f));
vec = trans * vec;
std::cout << vec.x << vec.y << vec.z << std::endl;

当我编译并运行此代码时，我得到了垃圾值(通常为NAN).该教程特别指出了实例化

When I compile and run this code, I get trash values (usually NAN). The tutorial specifically noted that instantiating

glm::mat4 trans;

默认情况下将为变量"trans"创建一个单位矩阵.我想这可能是问题所在，尽管我已经验证了glm会默认执行此操作.

would by default create an identity matrix for the varialbe "trans". I'm thinking that perhaps this is the issue, though I have verified that glm does do this by default.

如果有帮助，您可以找到整个源文件这里，位于第308行.非常感谢您的宝贵时间！

In case it would be helpful, you can find the entire source file here on line 308. I greatly appreciate your time!

推荐答案

您必须初始化矩阵变量glm::mat4 trans.

You have to initialize the matrix variable glm::mat4 trans.

glm API文档指的是 OpenGL着色语言规范4.20 .

5.4.2向量和矩阵构造器

如果向量构造函数只有一个标量参数，它将用于将构造的向量的所有分量初始化为该标量的值. 如果矩阵构造函数只有一个标量参数，则它将用于初始化矩阵对角线上的所有分量，并将其余分量初始化为0.0.

If there is a single scalar parameter to a vector constructor, it is used to initialize all components of the constructed vector to that scalar’s value. If there is a single scalar parameter to a matrix constructor, it is used to initialize all the components on the matrix’s diagonal, with the remaining components initialized to 0.0.

这意味着，可以通过单个参数1.0:glm::mat4(1.0f)初始化一个单位矩阵.

This means, that an identity matrix can be initialized by the single parameter 1.0: glm::mat4(1.0f).

以某种方式更改代码:

glm::mat4 trans(1.0f);

另请参见 OpenGL数学(GLM)； 2.向量和矩阵构造器

See also OpenGL Mathematics (GLM); 2. Vector and Matrix Constructors

这篇关于glm返回nan进行简单翻译的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！