[3] 球(Sphere)图形的生成算法
顶点数据的生成
bool YfBuildSphereVertices
(
Yreal radius,
Yuint slices,
Yuint stacks,
YeOriginPose originPose,
Yuint vertexStriding,
Yuint vertexPos,
void* pVerticesBuffer
)
{
if (slices < || stacks < || !pVerticesBuffer)
{
return false;
} Yuint numVertices = slices * (stacks - ) + ; // 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 = -radius;
}
else if (originPose == YE_ORIGIN_POSE_BOTTOM)
{
originOffsetY = radius;
} Yreal* pSinList = YD_NEW_ARRAY(Yreal, slices);
Yreal* pCosList = YD_NEW_ARRAY(Yreal, slices);
Yreal angleXZ;
for (Yuint j = ; j < slices; j++)
{
angleXZ = YD_REAL_TWAIN_PI * j / slices;
pSinList[j] = yf_sin(angleXZ);
pCosList[j] = yf_cos(angleXZ);
} // 赋值
{
for (Yuint i = ; i < stacks; i++)
{
if (i == ) // 第一个顶点
{
nOffset = ;
curVertexPtr = (YsVector3*)(vertexPtr + nOffset);
curVertexPtr->x = 0.0f;
curVertexPtr->y = radius + originOffsetY;
curVertexPtr->z = 0.0f;
continue;
}
else if (i == stacks - ) // 最后一个顶点
{
nOffset = (numVertices - ) * vertexStriding;
curVertexPtr = (YsVector3*)(vertexPtr + nOffset);
curVertexPtr->x = 0.0f;
curVertexPtr->y = -radius + originOffsetY;
curVertexPtr->z = 0.0f;
continue;
} Yreal angleY = YD_REAL_PI * i / (stacks - );
Yreal posY = radius * yf_cos(angleY);
Yreal radiusXZ = radius * yf_sin(angleY);
Yreal posX, posZ; for (Yuint j = ; j < slices; j++)
{
posX = radiusXZ * pSinList[j];
posZ = radiusXZ * pCosList[j];
nOffset = ((i - ) * slices + j + ) * vertexStriding;
curVertexPtr = (YsVector3*)(vertexPtr + nOffset);
curVertexPtr->x = posX;
curVertexPtr->y = posY + originOffsetY;
curVertexPtr->z = posZ;
}
}
} YD_SAFE_DELETE_ARRAY(pSinList);
YD_SAFE_DELETE_ARRAY(pCosList); return true;
}
三角形索引数据的生成
bool YfBuildSphereTriIndices
(
Yuint slices,
Yuint stacks,
YeIndexType indexType,
Yuint indexStriding,
Yuint indexPos,
void* pTriIndicesBuffer
)
{
if (slices < || stacks < || !pTriIndicesBuffer)
{
return false;
} Yuint numVertices = slices * (stacks - ) + ;
Yuint numTriangles = slices * (stacks - ) * ;
if (indexType == YE_INDEX_16_BIT &&
numVertices > YD_MAX_UNSIGNED_INT16)
{
return false;
} // 索引赋值
char* indexPtr = (char*)pTriIndicesBuffer + indexPos;
Yuint nOffset = ;
if (indexType == YE_INDEX_16_BIT)
{
YsTriIndex16* triIndexPtr = NULL; for (Yuint i = ; i < stacks - ; i++)
{
if (i == ) // 第一层
{
for (Yuint j = ; j < slices; j++)
{
nOffset = j * indexStriding;
triIndexPtr = (YsTriIndex16*)(indexPtr + nOffset);
triIndexPtr->index0 = ;
triIndexPtr->index1 = + j;
triIndexPtr->index2 = + (j + )%slices;
}
}
else if (i == stacks - ) // 最后一层
{
for (Yuint j = ; j < slices; j++)
{
nOffset = (numTriangles - slices + j) * indexStriding;
triIndexPtr = (YsTriIndex16*)(indexPtr + nOffset);
triIndexPtr->index0 = numVertices - ;
triIndexPtr->index1 = numVertices - - slices + (j + )%slices;
triIndexPtr->index2 = numVertices - - slices + j;
}
}
else
{
for (Yuint j = ; j < slices; j++)
{
nOffset = ((i - )*slices * + slices + j * ) * indexStriding;
triIndexPtr = (YsTriIndex16*)(indexPtr + nOffset);
triIndexPtr->index0 = + slices * (i - ) + j;
triIndexPtr->index1 = + slices * i + j;
triIndexPtr->index2 = + slices * (i - ) + (j + )%slices; nOffset += indexStriding;
triIndexPtr = (YsTriIndex16*)(indexPtr + nOffset);
triIndexPtr->index0 = + slices * (i - ) + (j + )%slices;
triIndexPtr->index1 = + slices * i + j;
triIndexPtr->index2 = + slices * i + (j + )%slices;
}
}
}
}
else
{
YsTriIndex32* triIndexPtr = NULL; // 赋值
for (Yuint i = ; i < stacks - ; i++)
{
if (i == ) // 第一层
{
for (Yuint j = ; j < slices; j++)
{
nOffset = j * indexStriding;
triIndexPtr = (YsTriIndex32*)(indexPtr + nOffset);
triIndexPtr->index0 = ;
triIndexPtr->index1 = + j;
triIndexPtr->index2 = + (j + )%slices;
}
}
else if (i == stacks - ) // 最后一层
{
for (Yuint j = ; j < slices; j++)
{
nOffset = (numTriangles - slices + j) * indexStriding;
triIndexPtr = (YsTriIndex32*)(indexPtr + nOffset);
triIndexPtr->index0 = numVertices - ;
triIndexPtr->index1 = numVertices - - slices + (j + )%slices;
triIndexPtr->index2 = numVertices - - slices + j;
}
}
else
{
for (Yuint j = ; j < slices; j++)
{
nOffset = ((i - )*slices * + slices + j * ) * indexStriding;
triIndexPtr = (YsTriIndex32*)(indexPtr + nOffset);
triIndexPtr->index0 = + slices * (i - ) + j;
triIndexPtr->index1 = + slices * i + j;
triIndexPtr->index2 = + slices * (i - ) + (j + )%slices; nOffset += indexStriding;
triIndexPtr = (YsTriIndex32*)(indexPtr + nOffset);
triIndexPtr->index0 = + slices * (i - ) + (j + )%slices;
triIndexPtr->index1 = + slices * i + j;
triIndexPtr->index2 = + slices * i + (j + )%slices;
}
}
}
} return true;
}
线框索引数据的生成
bool YfBuildSphereWireIndices
(
Yuint slices,
Yuint stacks,
YeIndexType indexType,
Yuint indexStriding,
Yuint indexPos,
void* pWireIndicesBuffer
)
{
if (slices < || stacks < || !pWireIndicesBuffer)
{
return false;
} Yuint numVertices = slices * (stacks - ) + ;
if (indexType == YE_INDEX_16_BIT &&
numVertices > YD_MAX_UNSIGNED_INT16)
{
return false;
}
Yuint numLines = slices * (stacks - ) + slices * (stacks - ); char* indexPtr = (char*)pWireIndicesBuffer + indexPos;
Yuint nOffset = ; if (indexType == YE_INDEX_16_BIT)
{
YsLineIndex16* lineIndexPtr = NULL; // 行
for (Yuint j = ; j < stacks - ; j++)
{
for (Yuint i = ; i < slices; i++)
{
nOffset = ((j - )*slices + i) * indexStriding;
lineIndexPtr = (YsLineIndex16*)(indexPtr + nOffset);
lineIndexPtr->index0 = + (j - )*slices + i;
lineIndexPtr->index1 = + (j - )*slices + (i + )%slices;
}
} // 列
Yuint half = slices * (stacks - );
for (Yuint i = ; i < slices; i++)
{
for (Yuint j = ; j < stacks - ; j++)
{
nOffset = (half + (i*(stacks - ) + j)) * indexStriding;
lineIndexPtr = (YsLineIndex16*)(indexPtr + nOffset);
if (j == )
{
lineIndexPtr->index0 = ;
}
else
{
lineIndexPtr->index0 = + (j - )*slices + i;
}
if (j == stacks - )
{
lineIndexPtr->index1 = numVertices - ;
}
else
{
lineIndexPtr->index1 = + j*slices + i;
}
}
}
}
else
{
YsLineIndex32* lineIndexPtr = NULL; // 行
for (Yuint j = ; j < stacks - ; j++)
{
for (Yuint i = ; i < slices; i++)
{
nOffset = ((j - )*slices + i) * indexStriding;
lineIndexPtr = (YsLineIndex32*)(indexPtr + nOffset);
lineIndexPtr->index0 = + j*slices + i;
lineIndexPtr->index1 = + j*slices + (i + )%slices;
}
} // 列
Yuint half = slices * (stacks - );
for (Yuint i = ; i < slices; i++)
{
for (Yuint j = ; j < stacks - ; j++)
{
nOffset = (half + (i*(stacks - ) + j)) * indexStriding;
lineIndexPtr = (YsLineIndex32*)(indexPtr + nOffset);
if (j == )
{
lineIndexPtr->index0 = ;
}
else
{
lineIndexPtr->index0 = + (j - )*slices + i;
}
if (j == stacks - )
{
lineIndexPtr->index1 = numVertices - ;
}
else
{
lineIndexPtr->index1 = + j*slices + i;
}
}
}
} return true;
}
[3] 球(Sphere)图形的生成算法的更多相关文章
- [20] 鼓状物(Drum)图形的生成算法
顶点数据的生成 bool YfBuildDrumVertices ( Yreal radius, Yreal assistRadius, Yuint slices, Yuint stacks, YeO ...
- [17] 楼梯(Stairs)图形的生成算法
感觉这图形怎么看怎么像搓衣板. 顶点数据的生成 bool YfBuildStairsVertices ( Yreal width, Yreal length, Yreal height, Yuint ...
- [19] 半球形(Hemisphere)图形的生成算法
顶点数据的生成 bool YfBuildHemisphereVertices ( Yreal radius, Yuint slices, Yuint stacks, YeOriginPose orig ...
- [18] 螺旋楼梯(Spiral Stairs)图形的生成算法
顶点数据的生成 bool YfBuildSpiralStairsVertices ( Yreal radius, Yreal assistRadius, Yreal height, Yuint sli ...
- [16] 螺旋面(Spire)图形的生成算法
顶点数据的生成 bool YfBuildSpireVertices ( Yreal radius, Yreal assistRadius, Yreal height, Yuint slices, Yu ...
- [15] 星星(Star)图形的生成算法
顶点数据的生成 bool YfBuildStarVertices ( Yreal radius, Yreal assistRadius, Yreal height, Yuint slices, YeO ...
- [14] 齿轮(Gear Wheel)图形的生成算法
顶点数据的生成 bool YfBuildGearwheelVertices ( Yreal radius, Yreal assistRadius, Yreal height, Yuint slices ...
- [13] 弧面(Arc)图形的生成算法
顶点数据的生成 bool YfBuildArcVertices ( Yreal radius, Yreal degree, Yreal height, Yuint slices, Yuint stac ...
- [12] 扇形体(Fan)图形的生成算法
顶点数据的生成 bool YfBuildFunVertices ( Yreal radius, Yreal degree, Yreal height, Yuint slices, YeOriginPo ...
随机推荐
- Django项目从零开始的大概脉络
Django项目从零开始脉络 创建虚拟环境,隔离项目python环境:mkvirtualenv -p /usr/bin/python3.6 envname 安装Django:pip install d ...
- Java反射机制demo(三)—获取类中的构造函数
Java反射机制demo(三)—获取类中的构造函数 1,获取类中所有的构造函数 如下面的代码中所示,这个类中显式的构造函数有五个. 空构造: public UserInfo() 带参构造有四个: pu ...
- 深入理解python中的select模块
简介 Python中的select模块专注于I/O多路复用,提供了select poll epoll三个方法(其中后两个在Linux中可用,windows仅支持select),另外也提供了kque ...
- android view的 绘制流程
韩梦飞沙 韩亚飞 313134555@qq.com yue31313 han_meng_fei_sha 首先是 从 视图根 这个类的 进行遍历 performTraversals 方法 开 ...
- 最大子段和问题Java实现
最大子段和问题 一.问题描述 给定长度为n的整数序列,a[1...n], 求[1,n]某个子区间[i , j]使得a[i]+…+a[j]和最大. 例如(-2,11,-4,13,-5,2)的最大子段和为 ...
- hdu 3613 扩展kmp+回文串
题目大意:给个字符串S,要把S分成两段T1,T2,每个字母都有一个对应的价值,如果T1,T2是回文串(从左往右或者从右往左读,都一样),那么他们就会有一个价值,这个价值是这个串的所有字母价值之和,如果 ...
- Codeforces Round #288 (Div. 2) C. Anya and Ghosts 模拟 贪心
C. Anya and Ghosts time limit per test 2 seconds memory limit per test 256 megabytes input standard ...
- ASP.NET 构建高性能网站 第6篇
内存问题概述 和CPU一样,内存也是一个直接影响服务端性能的重要的硬件资源. 一般来说,如果服务端内存不足,从导致以下两个问题产生: 1. 导致服务端把一些原本要写到内存中的数据,写到硬盘 ...
- 微信小程序 scroll-view隐藏横向滚动条
::-webkit-scrollbar { width: 0; height: 0; color: transparent; }
- linux系统时间同步,硬件时钟和系统时间同步,时区的设置
1.时间同步(手动): date -s "2015-07-15 22:13:30" hwclock --systohc (表示系统时间同步到硬件时钟) hwclo ...