# C++ Can anyone see where I have gone wrong? Unreal, 1 error in class

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This is from the unreal tutorial battery collector c++.

I'm learning unreal and am new to it so i couldn't guess why this is happening. Is it clear to anyone what i have to do to fix this?

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Your error says that your trying to assign a mesh as a Scene Component

PickupMesh = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("PickupMesh"));
RootComponent = PickupMesh; //This is where you make the mistake. A mesh != a object.

Look at the tutorial again and see what they do at this point.

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That's strange, we do the same thing in our project (assign a UStaticMeshComponent to RootComponent), and it works fine. UStaticMeshComponent inherits from USceneComponent, so such assignment is valid.

Does it work, if you do an explicit cast?

RootComponent = (USceneComponent*)PickupMesh;

Don't know, if it has anything to do with the problem, but it looks like you're using an older version of Visual Studio (2013?), while they recommend VS2017 for UE4.18 (although we use VS2015 without any issues).

UPDATE: I guess, it doesn't immediately follow, that the assignment of UStaticMeshComponent* to USceneComponent* is valid, only that a cast from UStaticMeshComponent* to USceneComponent* is. And unfortunately I'm not the right person to explain, whether such cast will happen implicitly, and what kind of constructor you need in order for it to happen.

Edited by dietrich

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@Scouting Ninja and @dietrich thank you for replying. I really appreciate the posts. I had to go and work later that day when I made my thread so I was unable to reply any sooner. I will try out what has been mentioned here and shall let you know how I get on. Thanks for the feedback.

edit: I'm using VS'15 btw.

Edited by GameDevCoder

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Introduction:
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The Actual Post:
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Scaling Matrix:
m_Impl->scale = glm::mat4(1.0f); m_Impl->scale = glm::scale(m_Impl->scale, glm::vec3(width, height, 0)); Verticies:
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#shader vertex #version 330 core layout(location = 0) in vec4 aPos; layout(location = 1) in vec2 aTexCoord; out vec2 texCoord; uniform mat4 u_MVP; void main() { gl_Position = u_MVP*aPos; texCoord = aTexCoord; } #shader fragment #version 330 core out vec4 colors; in vec2 texCoord; uniform sampler2D u_Texture; void main() { colors = texture(u_Texture, texCoord); }
Before Scaling (It's down there on the bottom left corner as a dot).

After Scaling

Problem: Why does the position also changes?? If you see my Verticies, the first position starts at 1.0f, 1.0f , so when i'm scaling it should stay at that position

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