-
Notifications
You must be signed in to change notification settings - Fork 2
/
TerrainPatch.cpp
250 lines (226 loc) · 7.83 KB
/
TerrainPatch.cpp
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
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
// Copyright © 2008-2012 Pioneer Developers. See AUTHORS.txt for details
// Licensed under the terms of the GPL v3. See licenses/GPL-3.txt
#include <cassert>
#include "utils.h"
#include "TerrainMesh.h"
#include "TerrainPatch.h"
#include "TerrainContext.h"
#include "GLvbo.h"
#include "vcacheopt.h"
#include "shaderHelper.h"
#include "GLfbo.h"
#include "GLprimitives.h"
// Include GLM
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <algorithm>
// constructor
TerrainPatch::TerrainPatch(const TerrainPatchContext &context_, TerrainMesh *pTerrainMesh_,
const glm::vec3 &v0_, const glm::vec3 &v1_, const glm::vec3 &v2_, const glm::vec3 &v3_,
const uint32_t depth_, const TerrainPatchID &ID_)
: mContext(context_), mpTerrainMesh(pTerrainMesh_), mV0(v0_), mV1(v1_), mV2(v2_), mV3(v3_),
mClipCentroid((v0_+v1_+v2_+v3_) * 0.25f), mCentroid(glm::normalize(mClipCentroid)), mDepth(depth_), mClipRadius(0.0f), mRoughLength(0.0f),
mPatchID(ID_), mHeightmap(0), mVBO(nullptr), mHasSplitRequest(false), parent(nullptr)
{
for (int i=0; i<NUM_KIDS; i++) {
edgeFriend[i] = nullptr;
kids[i] = nullptr;
}
mClipRadius = std::max(mClipRadius, glm::length(mV0-mClipCentroid));
mClipRadius = std::max(mClipRadius, glm::length(mV1-mClipCentroid));
mClipRadius = std::max(mClipRadius, glm::length(mV2-mClipCentroid));
mClipRadius = std::max(mClipRadius, glm::length(mV3-mClipCentroid));
const float fDepth = float(Clamp<uint32_t>(mDepth, 1, 5));
const float distMult = 5.0f / fDepth;
mRoughLength = GEOPATCH_SUBDIVIDE_AT_CAMDIST / powf(2.0f, fDepth) * distMult;
}
// destructor
TerrainPatch::~TerrainPatch()
{
for (int i=0; i<4; i++) {
if (edgeFriend[i]) {
edgeFriend[i]->NotifyEdgeFriendDeleted(this);
}
}
for (int i=0; i<NUM_KIDS; i++) {
edgeFriend[i] = nullptr;
if(kids[i]) {
delete kids[i];
kids[i] = nullptr;
}
}
if(glIsTexture(mHeightmap)==GL_TRUE) {
glDeleteTextures(1, &mHeightmap);
checkGLError();
}
if( mVBO ) {
delete mVBO;
mVBO = nullptr;
}
}
// Generates full-detail vertices, and also non-edge normals and colors
void TerrainPatch::GenerateMesh() {
////////////////////////////////////////////////////////////////
// Create the base mesh that the heightmap will modify
glm::vec3 *vts = mContext.vertexs();
GLfloat *pUV = mContext.uvs();
assert(nullptr!=vts);
const float fracStep = mContext.meshLerpStep();
for (uint32_t y=0; y<mContext.edgeLen(); y++) {
for (uint32_t x=0; x<mContext.edgeLen(); x++) {
const float xfrac = float(x) * fracStep;
const float yfrac = float(y) * fracStep;
assert(xfrac<=1.0 && yfrac<=1.0);
const glm::vec3 p = GetSpherePoint(xfrac, yfrac);
*(vts++) = p;
*(pUV++) = xfrac;
*(pUV++) = yfrac;
}
}
assert(vts == &mContext.vertexs()[mContext.NUM_MESH_VERTS()]);
assert(pUV == &mContext.uvs()[mContext.NUM_MESH_VERTS()*2]);
// now create the VBO
assert(nullptr==mVBO);
mVBO = new CGLvbo( mContext.NUM_MESH_VERTS(), &mContext.vertexs()[0], nullptr, mContext.uvs() );
}
void TerrainPatch::ReceiveHeightmaps(const SSplitResult *psr)
{
if (mDepth < psr->depth) {
// this should work because each depth should have a common history
const uint32_t kidIdx = psr->data[0].patchID.GetPatchIdx(mDepth+1);
kids[kidIdx]->ReceiveHeightmaps(psr);
} else {
const int nD = mDepth+1;
for (int i=0; i<4; i++)
{
kids[i] = new TerrainPatch(mContext, mpTerrainMesh,
psr->data[i].v0, psr->data[i].v1, psr->data[i].v2, psr->data[i].v3,
nD, mPatchID.NextPatchID(nD,i));
}
for (int i=0; i<4; i++)
{
kids[i]->ReceiveHeightmapTex(psr->data[i].texID);
}
// hm.. edges. Not right to pass this
// edgeFriend...
kids[0]->edgeFriend[0] = GetEdgeFriendForKid(0, 0);
kids[0]->edgeFriend[1] = kids[1];
kids[0]->edgeFriend[2] = kids[3];
kids[0]->edgeFriend[3] = GetEdgeFriendForKid(0, 3);
kids[1]->edgeFriend[0] = GetEdgeFriendForKid(1, 0);
kids[1]->edgeFriend[1] = GetEdgeFriendForKid(1, 1);
kids[1]->edgeFriend[2] = kids[2];
kids[1]->edgeFriend[3] = kids[0];
kids[2]->edgeFriend[0] = kids[1];
kids[2]->edgeFriend[1] = GetEdgeFriendForKid(2, 1);
kids[2]->edgeFriend[2] = GetEdgeFriendForKid(2, 2);
kids[2]->edgeFriend[3] = kids[3];
kids[3]->edgeFriend[0] = kids[0];
kids[3]->edgeFriend[1] = kids[2];
kids[3]->edgeFriend[2] = GetEdgeFriendForKid(3, 2);
kids[3]->edgeFriend[3] = GetEdgeFriendForKid(3, 3);
kids[0]->parent = kids[1]->parent = kids[2]->parent = kids[3]->parent = this;
for (int i=0; i<4; i++) {
kids[i]->GenerateMesh();
}
for (int i=0; i<4; i++) {
if(edgeFriend[i]) {
edgeFriend[i]->NotifyEdgeFriendSplit(this);
}
}
mHasSplitRequest = false;
}
}
void TerrainPatch::ReceiveHeightmapTex(const GLuint tex)
{
mHeightmap = tex;
}
void TerrainPatch::Render()
{
if (kids[0]) {
for (int i=0; i<4; i++) {
kids[i]->Render();
}
}
else if(parent)
{
#if TEST_CASE
//glm::vec4 patchColour(float(mDepth+1) * (1.0f/float(GEOPATCH_MAX_DEPTH)), 0.0f, float(GEOPATCH_MAX_DEPTH-mDepth) * (1.0f/float(GEOPATCH_MAX_DEPTH)), 1.0f);
static const glm::vec4 patchColour[6] = {
glm::vec4(1.0f, 0.0f, 0.0f, 1.0f), // problem child - red (meets purple & cyan)
glm::vec4(0.0f, 1.0f, 0.0f, 1.0f), // green
glm::vec4(0.0f, 0.0f, 1.0f, 1.0f), // blue
glm::vec4(1.0f, 0.0f, 1.0f, 1.0f), // purple
glm::vec4(0.0f, 1.0f, 1.0f, 1.0f), // cyan
glm::vec4(1.0f, 1.0f, 0.0f, 1.0f) // problem child - yellow (meets purple & blue)
};
glUniform4fv(mContext.patchColourID(), 1, &patchColour[mPatchID.GetPatchFaceIdx()][0]);
#else
glm::vec4 patchColour(float(mDepth+1) * (1.0f/float(GEOPATCH_MAX_DEPTH)), 0.0f, float(GEOPATCH_MAX_DEPTH-mDepth) * (1.0f/float(GEOPATCH_MAX_DEPTH)), 1.0f);
//glm::vec4 patchColour(1.0f, 1.0f, 1.0f, 1.0f);
glUniform4fv(mContext.patchColourID(), 1, &patchColour[0]);
#endif
glUniform3fv(mContext.patchV0ID(), 1, &mV0[0]);
glUniform3fv(mContext.patchV1ID(), 1, &mV1[0]);
glUniform3fv(mContext.patchV2ID(), 1, &mV2[0]);
glUniform3fv(mContext.patchV3ID(), 1, &mV3[0]);
glUniform1i(mContext.patchTexHeightmapID(), 0); //Texture unit 0 is for base images.
// bind the heightmap texture
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, mHeightmap);
assert(nullptr != mVBO);
ScopedBindRelease<CGLvbo> vbo(*mVBO);
// Index buffer
const GLuint iBufIndex = determineIndexbuffer();
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mContext.elementBuffers(iBufIndex));
// Draw the triangles !
glDrawElements(
GL_TRIANGLES, // mode
mContext.elementBuffersIndexCount(iBufIndex), // count
GL_UNSIGNED_SHORT, // type
nullptr // element array buffer offset
);
checkGLError();
}
}
void TerrainPatch::LODUpdate(const glm::vec3 &campos) {
// there should be no LODUpdate'ing when we have active split requests
if(mHasSplitRequest)
return;
bool canSplit = true;
bool canMerge = (kids[0]!=NULL);
// always split at first level
if (parent) {
for (int i=0; i<4; i++) {
if (!edgeFriend[i]) {
canSplit = false;
break;
} else if (edgeFriend[i]->mDepth < mDepth) {
canSplit = false;
break;
}
}
const float centroidDist = glm::length(campos - mCentroid);
const bool errorSplit = (centroidDist < mRoughLength);
if( !(canSplit && (mDepth < GEOPATCH_MAX_DEPTH) && errorSplit) )
{
canSplit = false;
}
}
if (canSplit) {
if (!kids[0]) {
mHasSplitRequest = true;
SSplitRequestDescription *desc = new SSplitRequestDescription(mV0, mV1, mV2, mV3, mCentroid, mDepth, mPatchID);
mpTerrainMesh->AddSplitRequest(desc);
} else {
for (int i=0; i<4; i++) {
kids[i]->LODUpdate(campos);
}
}
} else if (canMerge) {
for (int i=0; i<4; i++) {
delete kids[i];
kids[i] = nullptr;
}
}
}