顶点数据的生成
bool YfBuildGearwheelVertices
(
Yreal radius,
Yreal assistRadius,
Yreal height,
Yuint slices,
YeOriginPose originPose,
Yuint vertexStriding,
Yuint vertexPos,
void* pVerticesBuffer
)
{
if (slices < || !pVerticesBuffer)
{
return false;
} Yuint numVertices = slices* + ; // 顶点赋值
char* vertexPtr = (char*)pVerticesBuffer + vertexPos;
YsVector3* curVertexPtr = NULL;
Yuint nOffset = ; Yreal originOffsetY = 0.0f;
if (originPose == YE_ORIGIN_POSE_TOP)
{
originOffsetY = -height;
}
else if (originPose == YE_ORIGIN_POSE_CENTER)
{
originOffsetY = -height * 0.5f;
} // 柱顶顶点赋值
{
nOffset = ;
curVertexPtr = (YsVector3*)(vertexPtr + nOffset);
curVertexPtr->x = 0.0f;
curVertexPtr->y = height + originOffsetY;
curVertexPtr->z = 0.0f;
} // 柱底顶点赋值
{
nOffset = (numVertices - ) * vertexStriding;
curVertexPtr = (YsVector3*)(vertexPtr + nOffset);
curVertexPtr->x = 0.0f;
curVertexPtr->y = originOffsetY;
curVertexPtr->z = 0.0f;
} Yreal angleXZ;
Yreal posX, posZ;
Yreal fRadius;
for (Yuint i = ; i < *slices; i++)
{
angleXZ = YD_REAL_TWAIN_PI * i / (slices*);
posX = yf_sin(angleXZ);
posZ = yf_cos(angleXZ);
fRadius = (i% == ) ? radius : assistRadius; // 上顶点
{
nOffset = ( + i) * vertexStriding;
curVertexPtr = (YsVector3*)(vertexPtr + nOffset);
curVertexPtr->x = fRadius * posX;
curVertexPtr->y = height + originOffsetY;
curVertexPtr->z = fRadius * posZ;
} // 下顶点
{
nOffset = ( + *slices + i) * vertexStriding;
curVertexPtr = (YsVector3*)(vertexPtr + nOffset);
curVertexPtr->x = fRadius * posX;
curVertexPtr->y = originOffsetY;
curVertexPtr->z = fRadius * posZ;
}
} return true;
}
三角形索引数据的生成
bool YfBuildGearwheelTriIndices
(
Yuint slices,
YeIndexType indexType,
Yuint indexStriding,
Yuint indexPos,
void* pTriIndicesBuffer
)
{
if (slices < || !pTriIndicesBuffer)
{
return false;
} Yuint numVertices = slices* + ;
if (indexType == YE_INDEX_16_BIT &&
numVertices > YD_MAX_UNSIGNED_INT16)
{
return false;
}
Yuint numTriangles = slices * ; // 索引赋值
char* indexPtr = (char*)pTriIndicesBuffer + indexPos;
Yuint nOffset = ;
if (indexType == YE_INDEX_16_BIT)
{
YsTriIndex16* triIndexPtr = NULL;
for (Yuint i = ; i < * slices; i++)
{
nOffset = (i * ) * indexStriding;
triIndexPtr = (YsTriIndex16*)(indexPtr + nOffset);
triIndexPtr->index0 = ;
triIndexPtr->index1 = + i;
triIndexPtr->index2 = + (i + ) % (*slices); nOffset += indexStriding;
triIndexPtr = (YsTriIndex16*)(indexPtr + nOffset);
triIndexPtr->index0 = numVertices - ;
triIndexPtr->index1 = + slices* + (i + ) % (*slices);
triIndexPtr->index2 = + slices* + i; nOffset += indexStriding;
triIndexPtr = (YsTriIndex16*)(indexPtr + nOffset);
triIndexPtr->index0 = + i;
triIndexPtr->index1 = + slices* + i;
triIndexPtr->index2 = + (i + ) % (*slices); nOffset += indexStriding;
triIndexPtr = (YsTriIndex16*)(indexPtr + nOffset);
triIndexPtr->index0 = + (i + ) % (*slices);
triIndexPtr->index1 = + slices* + i;
triIndexPtr->index2 = + slices* + (i + ) % (*slices);
}
}
else
{
YsTriIndex32* triIndexPtr = NULL;
for (Yuint i = ; i < * slices; i++)
{
nOffset = (i * ) * indexStriding;
triIndexPtr = (YsTriIndex32*)(indexPtr + nOffset);
triIndexPtr->index0 = ;
triIndexPtr->index1 = + i;
triIndexPtr->index2 = + (i + ) % (*slices); nOffset += indexStriding;
triIndexPtr = (YsTriIndex32*)(indexPtr + nOffset);
triIndexPtr->index0 = numVertices - ;
triIndexPtr->index1 = + slices* + (i + ) % (*slices);
triIndexPtr->index2 = + slices* + i; nOffset += indexStriding;
triIndexPtr = (YsTriIndex32*)(indexPtr + nOffset);
triIndexPtr->index0 = + i;
triIndexPtr->index1 = + slices* + i;
triIndexPtr->index2 = + (i + ) % (*slices); nOffset += indexStriding;
triIndexPtr = (YsTriIndex32*)(indexPtr + nOffset);
triIndexPtr->index0 = + (i + ) % (*slices);
triIndexPtr->index1 = + slices* + i;
triIndexPtr->index2 = + slices* + (i + ) % (*slices);
}
} return true;
}
线框索引数据的生成
bool YfBuildGearwheelWireIndices
(
Yuint slices,
YeIndexType indexType,
Yuint indexStriding,
Yuint indexPos,
void* pWireIndicesBuffer
)
{
if (slices < || !pWireIndicesBuffer)
{
return false;
} Yuint numVertices = (slices*) * + ;
Yuint numLines = (slices*) * ;
if (indexType == YE_INDEX_16_BIT &&
numVertices > YD_MAX_UNSIGNED_INT16)
{
return false;
} // 索引赋值
char* indexPtr = (char*)pWireIndicesBuffer + indexPos;
Yuint nOffset = ;
if (indexType == YE_INDEX_16_BIT)
{
YsLineIndex16* lineIndexPtr = NULL;
for (Yuint i = ; i < * slices; i++)
{
nOffset = (i * ) * indexStriding;
lineIndexPtr = (YsLineIndex16*)(indexPtr + nOffset);
lineIndexPtr->index0 = + i;
lineIndexPtr->index1 = + (i + )%(slices*); nOffset += indexStriding;
lineIndexPtr = (YsLineIndex16*)(indexPtr + nOffset);
lineIndexPtr->index0 = + slices* + i;
lineIndexPtr->index1 = + slices* + (i + )%(slices*); nOffset += indexStriding;
lineIndexPtr = (YsLineIndex16*)(indexPtr + nOffset);
lineIndexPtr->index0 = + i;
lineIndexPtr->index1 = + slices* + i;
} Yuint half = * slices * indexStriding;
for (Yuint i = ; i < slices; i++)
{
nOffset = half + (i * ) * indexStriding;
lineIndexPtr = (YsLineIndex16*)(indexPtr + nOffset);
lineIndexPtr->index0 = ;
lineIndexPtr->index1 = + i* + ; nOffset += indexStriding;
lineIndexPtr = (YsLineIndex16*)(indexPtr + nOffset);
lineIndexPtr->index0 = numVertices - ;
lineIndexPtr->index1 = + slices* + i* + ;
}
}
else
{
YsLineIndex32* lineIndexPtr = NULL;
for (Yuint i = ; i < * slices; i++)
{
nOffset = (i * ) * indexStriding;
lineIndexPtr = (YsLineIndex32*)(indexPtr + nOffset);
lineIndexPtr->index0 = + i;
lineIndexPtr->index1 = + (i + )%(slices*); nOffset += indexStriding;
lineIndexPtr = (YsLineIndex32*)(indexPtr + nOffset);
lineIndexPtr->index0 = + slices* + i;
lineIndexPtr->index1 = + slices* + (i + )%(slices*); nOffset += indexStriding;
lineIndexPtr = (YsLineIndex32*)(indexPtr + nOffset);
lineIndexPtr->index0 = + i;
lineIndexPtr->index1 = + slices* + i;
} Yuint half = * slices * indexStriding;
for (Yuint i = ; i < slices; i++)
{
nOffset = half + (i * ) * indexStriding;
lineIndexPtr = (YsLineIndex32*)(indexPtr + nOffset);
lineIndexPtr->index0 = ;
lineIndexPtr->index1 = + i* + ; nOffset += indexStriding;
lineIndexPtr = (YsLineIndex32*)(indexPtr + nOffset);
lineIndexPtr->index0 = numVertices - ;
lineIndexPtr->index1 = + slices* + i* + ;
}
} return true;
}