DirectX 11：着色器无法创建世界视图矩阵

Question

After coming across this problem here , where the the Entity::draw() call would not be displayed due to the vertex shader values returning 0 on multiplication with the world view matrix.

The problem was funneled to a faulty constant buffer input. However, after checking the values, I can't seem to understand the problem at hand. I pre-multiplied the World, View, and Projection matrices:

mWorld = XMMatrixIdentity();
mView = XMMatrixLookAtLH(Eye, At, Up);
mProjection = XMMatrixPerspectiveFovLH(XM_PIDIV2, 1.0, 0.0f, 1000.0f);
mWVP = mWorld*mView*mProjection;

mWVP

-0.999999940, 0.000000000,  0.000000000, 0.000000000
 0.000000000, 0.999999940,  0.000000000, 0.000000000
 0.000000000, 0.000000000, -1.00000000, -1.00000000
 0.000000000, 0.000000000,  5.00000000,  5.00000000

mWVP enters the constant buffer after being transposed:

WorldCB.mWorldVP = XMMatrixTranspose(mWVP);
DeviceContext->UpdateSubresource(MatrixBuffer, 0, NULL, &WorldCB, 0, 0);
DeviceContext->VSSetConstantBuffers(0, 1, &MatrixBuffer);

XMMatrixTranspose(mWVP);

-0.999999940, 0.000000000,  0.000000000, 0.000000000
 0.000000000, 0.999999940,  0.000000000, 0.000000000
 0.000000000, 0.000000000, -1.00000000,  5.00000000
 0.000000000, 0.000000000, -1.00000000,  5.00000000

Which looks OK, at least to me. Next my shader starts doing its thing, but here's where things get funky, checking the disassembly yields that when:

output.position = mul(position, WVP);

Vertex Shader:
00000000  dp4 o0.x, v0.xyzw, cb0[0].xyzw  
00000001  dp4 o0.y, v0.xyzw, cb0[1].xyzw  
00000002  dp4 o0.z, v0.xyzw, cb0[2].xyzw  
00000003  dp4 o0.w, v0.xyzw, cb0[3].xyzw  
00000004  mov o1.xyzw, v1.xyzw  

For each multiplication, values return 0. And if output.position = position; Values are correct, and the box displays, but not inside the world transformation.

The full shader file below:

cbuffer ConstantBuffer:register(b0)
{
    matrix WVP;
}

struct VOut
{
    float4 position : SV_POSITION;
    float4 color : COLOR;
};

VOut VShader(float4 position : POSITION, float4 color : COLOR)
{
    VOut output;
    output.position = mul(position, WVP); // position;
    output.color = color;

    return output;
}


float4 PShader(float4 position : SV_POSITION, float4 color : COLOR) : SV_TARGET
{
     return color;
}

Edit: Also noted that the Transpose of the World matrix equals zero:

ObjectSpace = m_Scale*m_Rotation*m_Translate;
mWVP = ObjectSpace*direct3D.mView*direct3D.mProjection;

LocalWorld.mWorldVP = XMMatrixTranspose(wWVP);

XMMatrixTranspose(wWVP) comes out:

0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0

And is likely the problem. Any guesses as to why the transpose of a matrix would equal 0?

Answer 1

The near plane of the perspective projection must be some value larger than zero. If it is zero, then the near plane is exactly where the camera is located, and everything in the scene converges to a single point.