Progressive Mesh in DirectX
2000160114 Seung ho
Lee
2000160207 Hyun taek
Kwon
What is Progressive Mesh?
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Level of Detail (LOD)
Progressive simplification or detail Mesh
Overview of Progressive Mesh
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Edge collapse or Vertex Split
Selective Refinement
Edge collapse or Vertex Split
Selective Refinement
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Use Vertex History
The Pipeline of DirectX Mesh
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ID3DXMesh interface
ID3DXPMesh interface
ID3DXMesh interface
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General Mesh interface
Buffers
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–
–
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Vertex Buffer
Index Buffer
Attribute Buffer
Functions
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DrawSubset(DWORD n);
ID3DXPMesh
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Progressive Mesh interface
Make from ID3DXMesh
Using Progressive Mesh interface
Implementation
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Implement from ID3DXMesh
Using Vertex Buffer and Index Buffer
Class Gmesh
Vertex Node Tree, History
Rendering Pipeline
Read PM File
Make GMesh
Write in
Mesh Buffer
Draw Mesh
Result
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Rabbit
View-Dependent Refinement
1. Definitions
2. Refinement Criteria
3. Implementation
1. Definitions (1)
- Active vertex, Active face
A vertex or face is active if it exists
in the selectively refined mesh Ms.
1. Definitions (2)
- Vertex hierarchy
1. Definitions (3)
- Legal
2. Refinement Criteria
(1) View frustum
Coarsen regions outsize the view frustum
(2) Surface orientation
Coarsen regions oriented away from viewer
(3) Screen-space geometric error
Makes the difference between approximate surface
M and the original M^ small
2. Refinement Criteria (1)
- Bounding Sphere
2. Refinement Criteria (1)
- Out of View frustum
Red lines show distance
2. Refinement Criteria (2)
- Cone of normals
Unnecessary to split if
2. Refinement Criteria (3)
- Distance
The distance between the approximate surface M
and the original M^, when projected on the screen, is
every where less than a screen-space tolerance r.
3. Implementation
- ListNode *ActiveVertexHead
double linked list of active vertex
- ListNode *RootVertexHead
Double linked list of root vertex
3. Implementation
Active Vertex
v1
v2
v3
Qrefine()
v1
v3
v4
v5
v6
v6
v21
Split
v4
v5
v22