1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
|
// Geometric Tools, LLC
// Copyright (c) 1998-2014
// Distributed under the Boost Software License, Version 1.0.
// http://www.boost.org/LICENSE_1_0.txt
// http://www.geometrictools.com/License/Boost/LICENSE_1_0.txt
//
// File Version: 5.0.0 (2010/01/01)
#include "Wm5GraphicsPCH.h"
#include "Wm5TerrainPage.h"
#include "Wm5StandardMesh.h"
#include "Wm5VertexBufferAccessor.h"
using namespace Wm5;
WM5_IMPLEMENT_RTTI(Wm5, TriMesh, TerrainPage);
WM5_IMPLEMENT_STREAM(TerrainPage);
WM5_IMPLEMENT_FACTORY(TerrainPage);
WM5_IMPLEMENT_DEFAULT_NAMES(TriMesh, TerrainPage);
//----------------------------------------------------------------------------
TerrainPage::TerrainPage (VertexFormat* vformat, int size,
unsigned short* heights, const Float2& origin, float minElevation,
float maxElevation, float spacing)
:
mSize(size),
mSizeM1(size - 1),
mHeights(heights),
mOrigin(origin),
mMinElevation(minElevation),
mMaxElevation(maxElevation),
mSpacing(spacing)
{
// size = 2^p + 1, p <= 7
assertion(size == 3 || size == 5 || size == 9 || size == 17
|| size == 33 || size == 65 || size == 129, "Invalid page size\n");
mInvSpacing = 1.0f/mSpacing;
mMultiplier = (mMaxElevation - mMinElevation)/65535.0f;
// Create a mesh for the page.
float ext = mSpacing*mSizeM1;
TriMesh* mesh = StandardMesh(vformat).Rectangle(mSize, mSize, ext, ext);
mVFormat = vformat;
mVBuffer = mesh->GetVertexBuffer();
mIBuffer = mesh->GetIndexBuffer();
delete0(mesh);
// Modify the vertices to use the terrain data.
VertexBufferAccessor vba(mVFormat, mVBuffer);
int numVertices = mVBuffer->GetNumElements();
for (int i = 0; i < numVertices; ++i)
{
int x = i % mSize;
int y = i / mSize;
vba.Position<Float3>(i) = Float3(GetX(x), GetY(y), GetHeight(i));
}
UpdateModelSpace(Visual::GU_NORMALS);
}
//----------------------------------------------------------------------------
TerrainPage::~TerrainPage ()
{
delete1(mHeights);
}
//----------------------------------------------------------------------------
float TerrainPage::GetHeight (float x, float y) const
{
float xGrid = (x - mOrigin[0])*mInvSpacing;
if (xGrid < 0.0f || xGrid >= (float)mSizeM1)
{
// Location not in page.
return Mathf::MAX_REAL;
}
float yGrid = (y - mOrigin[1])*mInvSpacing;
if (yGrid < 0.0f || yGrid >= (float)mSizeM1)
{
// Location not in page.
return Mathf::MAX_REAL;
}
float fCol = Mathf::Floor(xGrid);
int iCol = (int)fCol;
float fRow = Mathf::Floor(yGrid);
int iRow = (int)fRow;
int index = iCol + mSize*iRow;
float dx = xGrid - fCol;
float dy = yGrid - fRow;
float h00, h10, h01, h11, height;
if ((iCol & 1) == (iRow & 1))
{
float diff = dx - dy;
h00 = mMinElevation + mMultiplier*mHeights[index];
h11 = mMinElevation + mMultiplier*mHeights[index + 1 + mSize];
if (diff > 0.0f)
{
h10 = mMinElevation + mMultiplier*mHeights[index + 1];
height = (1.0f - diff - dy)*h00 + diff*h10 + dy*h11;
}
else
{
h01 = mMinElevation + mMultiplier*mHeights[index + mSize];
height = (1.0f + diff - dx)*h00 - diff*h01 + dx*h11;
}
}
else
{
float sum = dx + dy;
h10 = mMinElevation + mMultiplier*mHeights[index + 1];
h01 = mMinElevation + mMultiplier*mHeights[index + mSize];
if (sum <= 1.0f)
{
h00 = mMinElevation + mMultiplier*mHeights[index];
height = (1.0f - sum)*h00 + dx*h10 + dy*h01;
}
else
{
h11 = mMinElevation + mMultiplier*mHeights[index + 1 + mSize];
height = (sum - 1.0f)*h11 + (1.0f - dy)*h10 + (1.0f - dx)*h01;
}
}
return height;
}
//----------------------------------------------------------------------------
//----------------------------------------------------------------------------
// Streaming support.
//----------------------------------------------------------------------------
TerrainPage::TerrainPage (LoadConstructor value)
:
TriMesh(value),
mSize(0),
mSizeM1(0),
mHeights(0),
mOrigin(Float2(0.0f, 0.0f)),
mMinElevation(0.0f),
mMaxElevation(0.0f),
mSpacing(0.0f),
mInvSpacing(0.0f),
mMultiplier(0.0f)
{
}
//----------------------------------------------------------------------------
void TerrainPage::Load (InStream& source)
{
WM5_BEGIN_DEBUG_STREAM_LOAD(source);
TriMesh::Load(source);
source.Read(mSize);
int numVertices = mSize*mSize;
source.ReadVR(numVertices, mHeights);
source.ReadAggregate(mOrigin);
source.Read(mMinElevation);
source.Read(mMaxElevation);
source.Read(mSpacing);
mSizeM1 = mSize - 1;
mInvSpacing = 1.0f/mSpacing;
mMultiplier = (mMaxElevation - mMinElevation)/65535.0f;
WM5_END_DEBUG_STREAM_LOAD(TerrainPage, source);
}
//----------------------------------------------------------------------------
void TerrainPage::Link (InStream& source)
{
TriMesh::Link(source);
}
//----------------------------------------------------------------------------
void TerrainPage::PostLink ()
{
TriMesh::PostLink();
}
//----------------------------------------------------------------------------
bool TerrainPage::Register (OutStream& target) const
{
return TriMesh::Register(target);
}
//----------------------------------------------------------------------------
void TerrainPage::Save (OutStream& target) const
{
WM5_BEGIN_DEBUG_STREAM_SAVE(target);
TriMesh::Save(target);
target.Write(mSize);
int numVertices = mSize*mSize;
target.WriteN(numVertices, mHeights);
target.WriteAggregate(mOrigin);
target.Write(mMinElevation);
target.Write(mMaxElevation);
target.Write(mSpacing);
WM5_END_DEBUG_STREAM_SAVE(TerrainPage, target);
}
//----------------------------------------------------------------------------
int TerrainPage::GetStreamingSize () const
{
int size = TriMesh::GetStreamingSize();
size += sizeof(mSize);
size += mSize*mSize*sizeof(mHeights[0]);
size += sizeof(mOrigin);
size += sizeof(mMinElevation);
size += sizeof(mMaxElevation);
size += sizeof(mSpacing);
return size;
}
//----------------------------------------------------------------------------
|
