private void ApplyStencilTest(StencilTest stencilTest)
{
if (_renderState.StencilTest.Enabled != stencilTest.Enabled)
{
Enable(EnableCap.StencilTest, stencilTest.Enabled);
_renderState.StencilTest.Enabled = stencilTest.Enabled;
}
if (stencilTest.Enabled)
{
ApplyStencil(StencilFace.Front, _renderState.StencilTest.FrontFace, stencilTest.FrontFace);
ApplyStencil(StencilFace.Back, _renderState.StencilTest.BackFace, stencilTest.BackFace);
}
}
private void ApplyStencilTest(StencilTest stencilTest)
{
if (_renderState.StencilTest.Enabled != stencilTest.Enabled)
{
Enable(EnableCap.StencilTest, stencilTest.Enabled);
_renderState.StencilTest.Enabled = stencilTest.Enabled;
}
if (stencilTest.Enabled)
{
ApplyStencil(StencilFace.Front, _renderState.StencilTest.FrontFace, stencilTest.FrontFace);
ApplyStencil(StencilFace.Back, _renderState.StencilTest.BackFace, stencilTest.BackFace);
}
}
public void Set(Context context, IList <Vector3D> positions)
{
//
// This method expects that the positions are ordered in a repeated pattern of
// below terrain, above terrain pairs.
//
// Wall mesh
//
Mesh wallMesh = new Mesh();
wallMesh.PrimitiveType = PrimitiveType.TriangleStrip;
//
// Positions
//
int numberOfLineSegments = (positions.Count / 2) - 1;
int numberOfVertices = 2 + numberOfLineSegments + numberOfLineSegments;
VertexAttributeDoubleVector3 positionsAttribute = new VertexAttributeDoubleVector3("position", numberOfVertices);
IList <Vector3D> tempPositions = positionsAttribute.Values;
wallMesh.Attributes.Add(positionsAttribute);
foreach (Vector3D v in positions)
{
tempPositions.Add(v);
}
//
// Vertex array
//
_wallVA = context.CreateVertexArray(wallMesh, _wallSP.VertexAttributes, BufferHint.StaticDraw);
//
// Line mesh
//
Mesh lineMesh = new Mesh();
lineMesh.PrimitiveType = PrimitiveType.LineStrip;
//
// Positions
//
positionsAttribute = new VertexAttributeDoubleVector3("position", numberOfVertices);
tempPositions = positionsAttribute.Values;
lineMesh.Attributes.Add(positionsAttribute);
foreach (Vector3D v in positions)
{
tempPositions.Add(v);
}
//
// Indices
//
int numIndices = 4 * numberOfLineSegments;
ushort[] indices = new ushort[numIndices];
int baseIndex = 1;
for (int i = 0; i < numIndices; i += 4, baseIndex += 2)
{
indices[i] = (ushort)baseIndex;
indices[i + 1] = (ushort)(baseIndex - 1);
indices[i + 2] = (ushort)(baseIndex + 1);
indices[i + 3] = (ushort)(baseIndex + 2);
}
IndexBuffer indexBuffer = Device.CreateIndexBuffer(BufferHint.StaticDraw, numIndices * sizeof(ushort));
indexBuffer.CopyFromSystemMemory(indices);
//
// Vertex array
//
_lineVA = context.CreateVertexArray(lineMesh, _wallSP.VertexAttributes, BufferHint.StaticDraw);
_lineVA.IndexBuffer = indexBuffer;
//
// State
//
_wallDrawState = new DrawState();
_wallDrawState.RenderState.FacetCulling.Enabled = false;
_wallDrawState.RenderState.DepthTest.Enabled = false;
_wallDrawState.RenderState.DepthMask = false;
_wallDrawState.VertexArray = _lineVA;
_wallDrawState.ShaderProgram = _wallSP;
_shadowVolumePassOne = new DrawState();
_shadowVolumePassOne.VertexArray = _lineVA;
_shadowVolumePassOne.ShaderProgram = _shadowVolumeSP;
_shadowVolumePassOne.RenderState.FacetCulling.Enabled = false;
_shadowVolumePassOne.RenderState.DepthMask = false;
_shadowVolumePassOne.RenderState.ColorMask = new ColorMask(false, false, false, false);
StencilTest stOne = _shadowVolumePassOne.RenderState.StencilTest;
stOne.Enabled = true;
stOne.FrontFace.DepthFailStencilPassOperation = StencilOperation.Decrement;
stOne.BackFace.DepthFailStencilPassOperation = StencilOperation.Increment;
_shadowVolumePassTwo = new DrawState();
_shadowVolumePassTwo.VertexArray = _lineVA;
_shadowVolumePassTwo.ShaderProgram = _shadowVolumeSP;
_shadowVolumePassTwo.RenderState.DepthMask = false;
StencilTest stTwo = _shadowVolumePassTwo.RenderState.StencilTest;
stTwo.Enabled = true;
stTwo.FrontFace.DepthFailStencilPassOperation = StencilOperation.Zero;
stTwo.FrontFace.DepthPassStencilPassOperation = StencilOperation.Zero;
stTwo.FrontFace.Function = StencilTestFunction.NotEqual;
stTwo.BackFace.DepthFailStencilPassOperation = StencilOperation.Zero;
stTwo.BackFace.DepthPassStencilPassOperation = StencilOperation.Zero;
stTwo.BackFace.Function = StencilTestFunction.NotEqual;
}