GLSL 将有效的 glm::mat4 矩阵转换为 nan 矩阵

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I follow tutorial http://www.mbsoftworks.sk/tutorials/opengl3/ and try to compile 10th example.

Everything work fine besides place I send (projection matrix mul modelview matrix) to the shader.

There is place where I send matrix:

//...
// render.cpp
    glm::mat4 projectionMatrix = *(oglControl->getProjectionMatrix());
    glm::mat4 cam = glm::translate(mModelView, cCamera.vEye);
    auto newM = projectionMatrix * cam;
    spDirectionalLight.setUniform("projectionMatrixMulModelViewMatrix",&newM);
//...

//...
// setUniform implementation
void CShaderProgram::setUniform(string sName, glm::mat4* mMatrices, int iCount)
{
    int iLoc = glGetUniformLocation(uiProgram, sName.c_str());
    glUniformMatrix4fv(iLoc, iCount, FALSE, (GLfloat*)mMatrices);
}
//...

and at the end mMatrices contain [mMatrix content ] .

Shader code

#version 330 core

uniform mat4 projectionMatrixMulModelViewMatrix;
uniform mat4 normalMatrix;

layout (location = 0) in vec3 inPosition;
layout (location = 1) in vec2 inCoord;
layout (location = 2) in vec3 inNormal;

out vec2 texCoord;

smooth out vec3 vNormal;

void main()
{
    gl_Position = projectionMatrixMulModelViewMatrix*vec4(inPosition, 1.0);
    texCoord = inCoord;
    vec4 vRes = normalMatrix*vec4(inNormal, 0.0);
    vNormal = vRes.xyz;
}

The result is blank screen. Renderdoc debugger tells me that gl_position matrix completely NaN. Renderdoc screeenshot

When I send glm::mat4(1) I got valid result.

Why after multiplication shader got NaN vector?

好像 VS2017 骗了我。我还没有在代码内部深处初始化矩阵：

glm::mat4 mModelView = cCamera.look();

glm::mat4 CFlyingCamera::look()
{   
    glm::mat4 result = glm::mat4(1.0f);
    result = glm::lookAt(vEye, vView, vUp);
    return result;
}

这是我的错

void CFlyingCamera::update()
{
    // Change camera view direction
    rotateWithMouse();

    // Get view direction
    glm::vec3 vMove = vView-vEye;
    vMove = glm::normalize(vMove);
    vMove *= fSpeed;

    // Get normal to view direction vector 
    glm::vec3 vStrafe = glm::cross(vView-vEye, vUp);
    vStrafe = glm::normalize(vStrafe);
    vStrafe *= fSpeed;

    int iMove = 0;
////
////
///// ERROR HERE, vMoveBy isn't initialized
    glm::vec3 vMoveBy;
///// 
////
////    
// Get vector of move
    if(Keys::key(iForw))vMoveBy += vMove*appMain.sof(1.0f);
    if(Keys::key(iBack))vMoveBy -= vMove*appMain.sof(1.0f);
    if(Keys::key(iLeft))vMoveBy -= vStrafe*appMain.sof(1.0f);
    if(Keys::key(iRight))vMoveBy += vStrafe*appMain.sof(1.0f);
    vEye += vMoveBy; vView += vMoveBy;
}

但是调试器还是给了我有效的矩阵。你知道为什么会这样吗？

你必须初始化mModelView = glm::mat4(1.0f)

实际上，mModelView 之前已经初始化了。这不是原因。glm::mat4 mModelView = cCamera.look();`glm::mat4 CFlyingCamera::look() { return glm::lookAt(vEye, vView, vUp); }

正如我之前提到的 mMatrix 是有效的，你可以在这里看到它

@Rabbid76：似乎不是重复的，因为 glm 矩阵没问题。问题可能是上传到着色器。

glUseProgram@DiliDup：你之前打过电话setUniform吗？的价值是多少iLoc？为什么调用不setUniform包含第三个参数