3D Scenes - Game Coding Complete - page 559

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might be a good idea to get out the graph paper. To be honest, that s how I created

this code in the first place!
The real trick to making the sky node special is the code inside VPreRender() :

HRESULT SkyNode::VPreRender(Scene *pScene)
{

Vec3 cameraPos = m_camera->VGet()->ToWorld().GetPosition();
Mat4x4 mat = m_Props.ToWorld();
mat.SetPosition(cameraPos);
VSetTransform(&mat);

return SceneNode::VPreRender(pScene);

}
This code grabs the camera position and moves the sky node exactly as the camera
moves. This gives a completely convincing illusion that the objects like sun, moon,
mountains, and other backgrounds rendered into the sky textures are extremely far
away, since they don t appear to move as the player moves.

The code to render the sky should look a little familiar, since you saw snippets of it at
the end of the previous chapter:

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HRESULT D3DSkyNode11::VRender(Scene *pScene)
{

HRESULT hr;
V_RETURN (m_VertexShader.SetupRender(pScene) );
V_RETURN (m_PixelShader.SetupRender(pScene, this) );

// Set vertex buffer
UINT stride = sizeof( D3D11Vertex_UnlitTextured );
UINT offset = 0;
DXUTGetD3D11DeviceContext()->
IASetVertexBuffers( 0, 1, &m_pVertexBuffer, &stride, &offset );

// Set index buffer
DXUTGetD3D11DeviceContext()->
IASetIndexBuffer( m_pIndexBuffer, DXGI_FORMAT_R16_UINT, 0 );

// Set primitive topology
DXUTGetD3D11DeviceContext()->
IASetPrimitiveTopology( D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST );

for (DWORD side = 0; side < m_sides; side++)
{

const char *suffix[] =
{ “ _n.jpg ” , “ _e.jpg ” , “ _s.jpg ” , “ _w.jpg ” , “ _u.jpg ” };