OpenGL - 转身投影

Question

我试着扭转我的gui。我有预测：

glm::mat4 my_projection = glm::mat4( 2.0/static_cast<float>(m_window->getSize().x), 0.0, 0.0, -1.0,
                         0.0, 2.0/static_cast<float>(m_window->getSize().y), 0.0, -1.0,
                         0.0, 0.0, -1.0, 0.0,
                         0.0, 0.0, 0.0, 1.0);

着色器：

#version 330 core

in vec3 pos;
in vec2 UV;
in vec4 col;

uniform vec2 translation;
uniform mat4 my_projection;

out vec2 vecUV;
out vec4 vecColor;

void main()
{   
    vec3 tran_pos = vec3(pos + vec3(translation, 0.0f));
    gl_Position = vec4(tran_pos, 1.0f) * my_projection;
    vecUV = UV;
    vecColor = col;
}

当我改变时，我不知道如何转身

m_window->getSize().x

到

-m_window->getSize().x 

和

m_window->getSize().y 

到

-m_window->getSize().y

一切都消失了。我怎么能扭转这个？

编辑:(解决方案）

glm::mat4 my_projection = glm::ortho(0.0f, (float)m_window->getSize().x, (float)m_window->getSize().y, 0.0f);


// Shader:
#version 330 core

in vec3 pos;
in vec2 UV;
in vec4 col;

uniform vec2 translation;
uniform mat4 my_projection;

out vec2 vecUV;
out vec4 vecColor;

void main()
{      
        vec3 tran_pos = vec3(pos + vec3(translation, 0.0f));
        gl_Position = my_projection * vec4(tran_pos, 1.0f);
        vecUV = UV;
        vecColor = col;
}

只需使用glm函数进行矩阵投影，然后按位置乘以投影。