minetest/src/mesh.cpp
Kahrl da686160c3 Make all mesh manipulators in mesh.cpp work with any vertex type
cloneMesh() has to use a switch in order to create a different
mesh buffer type depending on vertex type. (Credit: the new cloneMesh
was written by RealBadAngel.)

To avoid repetitive code, all other methods use getVertexPitchFromType()
to automatically adapt the indexing to the vertex type at runtime.
2016-01-15 04:18:32 +01:00

1111 lines
28 KiB
C++

/*
Minetest
Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "mesh.h"
#include "debug.h"
#include "log.h"
#include "irrMap.h"
#include <iostream>
#include <IAnimatedMesh.h>
#include <SAnimatedMesh.h>
// In Irrlicht 1.8 the signature of ITexture::lock was changed from
// (bool, u32) to (E_TEXTURE_LOCK_MODE, u32).
#if IRRLICHT_VERSION_MAJOR == 1 && IRRLICHT_VERSION_MINOR <= 7
#define MY_ETLM_READ_ONLY true
#else
#define MY_ETLM_READ_ONLY video::ETLM_READ_ONLY
#endif
static void applyFacesShading(video::SColor& color, float factor)
{
color.setRed(core::clamp(core::round32(color.getRed()*factor), 0, 255));
color.setGreen(core::clamp(core::round32(color.getGreen()*factor), 0, 255));
color.setBlue(core::clamp(core::round32(color.getBlue()*factor), 0, 255));
}
scene::IAnimatedMesh* createCubeMesh(v3f scale)
{
video::SColor c(255,255,255,255);
video::S3DVertex vertices[24] =
{
// Up
video::S3DVertex(-0.5,+0.5,-0.5, 0,1,0, c, 0,1),
video::S3DVertex(-0.5,+0.5,+0.5, 0,1,0, c, 0,0),
video::S3DVertex(+0.5,+0.5,+0.5, 0,1,0, c, 1,0),
video::S3DVertex(+0.5,+0.5,-0.5, 0,1,0, c, 1,1),
// Down
video::S3DVertex(-0.5,-0.5,-0.5, 0,-1,0, c, 0,0),
video::S3DVertex(+0.5,-0.5,-0.5, 0,-1,0, c, 1,0),
video::S3DVertex(+0.5,-0.5,+0.5, 0,-1,0, c, 1,1),
video::S3DVertex(-0.5,-0.5,+0.5, 0,-1,0, c, 0,1),
// Right
video::S3DVertex(+0.5,-0.5,-0.5, 1,0,0, c, 0,1),
video::S3DVertex(+0.5,+0.5,-0.5, 1,0,0, c, 0,0),
video::S3DVertex(+0.5,+0.5,+0.5, 1,0,0, c, 1,0),
video::S3DVertex(+0.5,-0.5,+0.5, 1,0,0, c, 1,1),
// Left
video::S3DVertex(-0.5,-0.5,-0.5, -1,0,0, c, 1,1),
video::S3DVertex(-0.5,-0.5,+0.5, -1,0,0, c, 0,1),
video::S3DVertex(-0.5,+0.5,+0.5, -1,0,0, c, 0,0),
video::S3DVertex(-0.5,+0.5,-0.5, -1,0,0, c, 1,0),
// Back
video::S3DVertex(-0.5,-0.5,+0.5, 0,0,1, c, 1,1),
video::S3DVertex(+0.5,-0.5,+0.5, 0,0,1, c, 0,1),
video::S3DVertex(+0.5,+0.5,+0.5, 0,0,1, c, 0,0),
video::S3DVertex(-0.5,+0.5,+0.5, 0,0,1, c, 1,0),
// Front
video::S3DVertex(-0.5,-0.5,-0.5, 0,0,-1, c, 0,1),
video::S3DVertex(-0.5,+0.5,-0.5, 0,0,-1, c, 0,0),
video::S3DVertex(+0.5,+0.5,-0.5, 0,0,-1, c, 1,0),
video::S3DVertex(+0.5,-0.5,-0.5, 0,0,-1, c, 1,1),
};
u16 indices[6] = {0,1,2,2,3,0};
scene::SMesh *mesh = new scene::SMesh();
for (u32 i=0; i<6; ++i)
{
scene::IMeshBuffer *buf = new scene::SMeshBuffer();
buf->append(vertices + 4 * i, 4, indices, 6);
// Set default material
buf->getMaterial().setFlag(video::EMF_LIGHTING, false);
buf->getMaterial().setFlag(video::EMF_BILINEAR_FILTER, false);
buf->getMaterial().MaterialType = video::EMT_TRANSPARENT_ALPHA_CHANNEL_REF;
// Add mesh buffer to mesh
mesh->addMeshBuffer(buf);
buf->drop();
}
scene::SAnimatedMesh *anim_mesh = new scene::SAnimatedMesh(mesh);
mesh->drop();
scaleMesh(anim_mesh, scale); // also recalculates bounding box
return anim_mesh;
}
void scaleMesh(scene::IMesh *mesh, v3f scale)
{
if (mesh == NULL)
return;
core::aabbox3d<f32> bbox;
bbox.reset(0, 0, 0);
u32 mc = mesh->getMeshBufferCount();
for (u32 j = 0; j < mc; j++) {
scene::IMeshBuffer *buf = mesh->getMeshBuffer(j);
const u32 stride = getVertexPitchFromType(buf->getVertexType());
u32 vertex_count = buf->getVertexCount();
u8 *vertices = (u8 *)buf->getVertices();
for (u32 i = 0; i < vertex_count; i++)
((video::S3DVertex *)(vertices + i * stride))->Pos *= scale;
buf->recalculateBoundingBox();
// calculate total bounding box
if (j == 0)
bbox = buf->getBoundingBox();
else
bbox.addInternalBox(buf->getBoundingBox());
}
mesh->setBoundingBox(bbox);
}
void translateMesh(scene::IMesh *mesh, v3f vec)
{
if (mesh == NULL)
return;
core::aabbox3d<f32> bbox;
bbox.reset(0, 0, 0);
u32 mc = mesh->getMeshBufferCount();
for (u32 j = 0; j < mc; j++) {
scene::IMeshBuffer *buf = mesh->getMeshBuffer(j);
const u32 stride = getVertexPitchFromType(buf->getVertexType());
u32 vertex_count = buf->getVertexCount();
u8 *vertices = (u8 *)buf->getVertices();
for (u32 i = 0; i < vertex_count; i++)
((video::S3DVertex *)(vertices + i * stride))->Pos += vec;
buf->recalculateBoundingBox();
// calculate total bounding box
if (j == 0)
bbox = buf->getBoundingBox();
else
bbox.addInternalBox(buf->getBoundingBox());
}
mesh->setBoundingBox(bbox);
}
void setMeshColor(scene::IMesh *mesh, const video::SColor &color)
{
if (mesh == NULL)
return;
u32 mc = mesh->getMeshBufferCount();
for (u32 j = 0; j < mc; j++) {
scene::IMeshBuffer *buf = mesh->getMeshBuffer(j);
const u32 stride = getVertexPitchFromType(buf->getVertexType());
u32 vertex_count = buf->getVertexCount();
u8 *vertices = (u8 *)buf->getVertices();
for (u32 i = 0; i < vertex_count; i++)
((video::S3DVertex *)(vertices + i * stride))->Color = color;
}
}
void shadeMeshFaces(scene::IMesh *mesh)
{
if (mesh == NULL)
return;
u32 mc = mesh->getMeshBufferCount();
for (u32 j = 0; j < mc; j++) {
scene::IMeshBuffer *buf = mesh->getMeshBuffer(j);
const u32 stride = getVertexPitchFromType(buf->getVertexType());
u32 vertex_count = buf->getVertexCount();
u8 *vertices = (u8 *)buf->getVertices();
for (u32 i = 0; i < vertex_count; i++) {
video::S3DVertex *vertex = (video::S3DVertex *)(vertices + i * stride);
video::SColor &vc = vertex->Color;
if (vertex->Normal.Y < -0.5) {
applyFacesShading (vc, 0.447213);
} else if (vertex->Normal.Z > 0.5) {
applyFacesShading (vc, 0.670820);
} else if (vertex->Normal.Z < -0.5) {
applyFacesShading (vc, 0.670820);
} else if (vertex->Normal.X > 0.5) {
applyFacesShading (vc, 0.836660);
} else if (vertex->Normal.X < -0.5) {
applyFacesShading (vc, 0.836660);
}
}
}
}
void setMeshColorByNormalXYZ(scene::IMesh *mesh,
const video::SColor &colorX,
const video::SColor &colorY,
const video::SColor &colorZ)
{
if (mesh == NULL)
return;
u16 mc = mesh->getMeshBufferCount();
for (u16 j = 0; j < mc; j++) {
scene::IMeshBuffer *buf = mesh->getMeshBuffer(j);
const u32 stride = getVertexPitchFromType(buf->getVertexType());
u32 vertex_count = buf->getVertexCount();
u8 *vertices = (u8 *)buf->getVertices();
for (u32 i = 0; i < vertex_count; i++) {
video::S3DVertex *vertex = (video::S3DVertex *)(vertices + i * stride);
f32 x = fabs(vertex->Normal.X);
f32 y = fabs(vertex->Normal.Y);
f32 z = fabs(vertex->Normal.Z);
if (x >= y && x >= z)
vertex->Color = colorX;
else if (y >= z)
vertex->Color = colorY;
else
vertex->Color = colorZ;
}
}
}
void rotateMeshXYby(scene::IMesh *mesh, f64 degrees)
{
u16 mc = mesh->getMeshBufferCount();
for (u16 j = 0; j < mc; j++) {
scene::IMeshBuffer *buf = mesh->getMeshBuffer(j);
const u32 stride = getVertexPitchFromType(buf->getVertexType());
u32 vertex_count = buf->getVertexCount();
u8 *vertices = (u8 *)buf->getVertices();
for (u32 i = 0; i < vertex_count; i++)
((video::S3DVertex *)(vertices + i * stride))->Pos.rotateXYBy(degrees);
}
}
void rotateMeshXZby(scene::IMesh *mesh, f64 degrees)
{
u16 mc = mesh->getMeshBufferCount();
for (u16 j = 0; j < mc; j++) {
scene::IMeshBuffer *buf = mesh->getMeshBuffer(j);
const u32 stride = getVertexPitchFromType(buf->getVertexType());
u32 vertex_count = buf->getVertexCount();
u8 *vertices = (u8 *)buf->getVertices();
for (u32 i = 0; i < vertex_count; i++)
((video::S3DVertex *)(vertices + i * stride))->Pos.rotateXZBy(degrees);
}
}
void rotateMeshYZby(scene::IMesh *mesh, f64 degrees)
{
u16 mc = mesh->getMeshBufferCount();
for (u16 j = 0; j < mc; j++) {
scene::IMeshBuffer *buf = mesh->getMeshBuffer(j);
const u32 stride = getVertexPitchFromType(buf->getVertexType());
u32 vertex_count = buf->getVertexCount();
u8 *vertices = (u8 *)buf->getVertices();
for (u32 i = 0; i < vertex_count; i++)
((video::S3DVertex *)(vertices + i * stride))->Pos.rotateYZBy(degrees);
}
}
void rotateMeshBy6dFacedir(scene::IMesh *mesh, int facedir)
{
int axisdir = facedir >> 2;
facedir &= 0x03;
u16 mc = mesh->getMeshBufferCount();
for (u16 j = 0; j < mc; j++) {
scene::IMeshBuffer *buf = mesh->getMeshBuffer(j);
const u32 stride = getVertexPitchFromType(buf->getVertexType());
u32 vertex_count = buf->getVertexCount();
u8 *vertices = (u8 *)buf->getVertices();
for (u32 i = 0; i < vertex_count; i++) {
video::S3DVertex *vertex = (video::S3DVertex *)(vertices + i * stride);
switch (axisdir) {
case 0:
if (facedir == 1)
vertex->Pos.rotateXZBy(-90);
else if (facedir == 2)
vertex->Pos.rotateXZBy(180);
else if (facedir == 3)
vertex->Pos.rotateXZBy(90);
break;
case 1: // z+
vertex->Pos.rotateYZBy(90);
if (facedir == 1)
vertex->Pos.rotateXYBy(90);
else if (facedir == 2)
vertex->Pos.rotateXYBy(180);
else if (facedir == 3)
vertex->Pos.rotateXYBy(-90);
break;
case 2: //z-
vertex->Pos.rotateYZBy(-90);
if (facedir == 1)
vertex->Pos.rotateXYBy(-90);
else if (facedir == 2)
vertex->Pos.rotateXYBy(180);
else if (facedir == 3)
vertex->Pos.rotateXYBy(90);
break;
case 3: //x+
vertex->Pos.rotateXYBy(-90);
if (facedir == 1)
vertex->Pos.rotateYZBy(90);
else if (facedir == 2)
vertex->Pos.rotateYZBy(180);
else if (facedir == 3)
vertex->Pos.rotateYZBy(-90);
break;
case 4: //x-
vertex->Pos.rotateXYBy(90);
if (facedir == 1)
vertex->Pos.rotateYZBy(-90);
else if (facedir == 2)
vertex->Pos.rotateYZBy(180);
else if (facedir == 3)
vertex->Pos.rotateYZBy(90);
break;
case 5:
vertex->Pos.rotateXYBy(-180);
if (facedir == 1)
vertex->Pos.rotateXZBy(90);
else if (facedir == 2)
vertex->Pos.rotateXZBy(180);
else if (facedir == 3)
vertex->Pos.rotateXZBy(-90);
break;
default:
break;
}
}
}
}
void recalculateBoundingBox(scene::IMesh *src_mesh)
{
core::aabbox3d<f32> bbox;
bbox.reset(0,0,0);
for (u16 j = 0; j < src_mesh->getMeshBufferCount(); j++) {
scene::IMeshBuffer *buf = src_mesh->getMeshBuffer(j);
buf->recalculateBoundingBox();
if (j == 0)
bbox = buf->getBoundingBox();
else
bbox.addInternalBox(buf->getBoundingBox());
}
src_mesh->setBoundingBox(bbox);
}
scene::IMesh* cloneMesh(scene::IMesh *src_mesh)
{
scene::SMesh* dst_mesh = new scene::SMesh();
for (u16 j = 0; j < src_mesh->getMeshBufferCount(); j++) {
scene::IMeshBuffer *buf = src_mesh->getMeshBuffer(j);
switch (buf->getVertexType()) {
case video::EVT_STANDARD: {
video::S3DVertex *v =
(video::S3DVertex *) buf->getVertices();
u16 *indices = (u16*)buf->getIndices();
scene::SMeshBuffer *temp_buf = new scene::SMeshBuffer();
temp_buf->append(v, buf->getVertexCount(),
indices, buf->getIndexCount());
dst_mesh->addMeshBuffer(temp_buf);
temp_buf->drop();
break;
}
case video::EVT_2TCOORDS: {
video::S3DVertex2TCoords *v =
(video::S3DVertex2TCoords *) buf->getVertices();
u16 *indices = (u16*)buf->getIndices();
scene::SMeshBufferTangents *temp_buf =
new scene::SMeshBufferTangents();
temp_buf->append(v, buf->getVertexCount(),
indices, buf->getIndexCount());
dst_mesh->addMeshBuffer(temp_buf);
temp_buf->drop();
break;
}
case video::EVT_TANGENTS: {
video::S3DVertexTangents *v =
(video::S3DVertexTangents *) buf->getVertices();
u16 *indices = (u16*)buf->getIndices();
scene::SMeshBufferTangents *temp_buf =
new scene::SMeshBufferTangents();
temp_buf->append(v, buf->getVertexCount(),
indices, buf->getIndexCount());
dst_mesh->addMeshBuffer(temp_buf);
temp_buf->drop();
break;
}
}
}
return dst_mesh;
}
scene::IMesh* convertNodeboxNodeToMesh(ContentFeatures *f)
{
scene::SMesh* dst_mesh = new scene::SMesh();
for (u16 j = 0; j < 6; j++)
{
scene::IMeshBuffer *buf = new scene::SMeshBuffer();
buf->getMaterial().setFlag(video::EMF_LIGHTING, false);
buf->getMaterial().setFlag(video::EMF_BILINEAR_FILTER, false);
dst_mesh->addMeshBuffer(buf);
buf->drop();
}
video::SColor c(255,255,255,255);
std::vector<aabb3f> boxes = f->node_box.fixed;
for(std::vector<aabb3f>::iterator
i = boxes.begin();
i != boxes.end(); ++i)
{
aabb3f box = *i;
f32 temp;
if (box.MinEdge.X > box.MaxEdge.X)
{
temp=box.MinEdge.X;
box.MinEdge.X=box.MaxEdge.X;
box.MaxEdge.X=temp;
}
if (box.MinEdge.Y > box.MaxEdge.Y)
{
temp=box.MinEdge.Y;
box.MinEdge.Y=box.MaxEdge.Y;
box.MaxEdge.Y=temp;
}
if (box.MinEdge.Z > box.MaxEdge.Z)
{
temp=box.MinEdge.Z;
box.MinEdge.Z=box.MaxEdge.Z;
box.MaxEdge.Z=temp;
}
// Compute texture coords
f32 tx1 = (box.MinEdge.X/BS)+0.5;
f32 ty1 = (box.MinEdge.Y/BS)+0.5;
f32 tz1 = (box.MinEdge.Z/BS)+0.5;
f32 tx2 = (box.MaxEdge.X/BS)+0.5;
f32 ty2 = (box.MaxEdge.Y/BS)+0.5;
f32 tz2 = (box.MaxEdge.Z/BS)+0.5;
f32 txc[24] = {
// up
tx1, 1-tz2, tx2, 1-tz1,
// down
tx1, tz1, tx2, tz2,
// right
tz1, 1-ty2, tz2, 1-ty1,
// left
1-tz2, 1-ty2, 1-tz1, 1-ty1,
// back
1-tx2, 1-ty2, 1-tx1, 1-ty1,
// front
tx1, 1-ty2, tx2, 1-ty1,
};
v3f min = box.MinEdge;
v3f max = box.MaxEdge;
video::S3DVertex vertices[24] =
{
// up
video::S3DVertex(min.X,max.Y,max.Z, 0,1,0, c, txc[0],txc[1]),
video::S3DVertex(max.X,max.Y,max.Z, 0,1,0, c, txc[2],txc[1]),
video::S3DVertex(max.X,max.Y,min.Z, 0,1,0, c, txc[2],txc[3]),
video::S3DVertex(min.X,max.Y,min.Z, 0,1,0, c, txc[0],txc[3]),
// down
video::S3DVertex(min.X,min.Y,min.Z, 0,-1,0, c, txc[4],txc[5]),
video::S3DVertex(max.X,min.Y,min.Z, 0,-1,0, c, txc[6],txc[5]),
video::S3DVertex(max.X,min.Y,max.Z, 0,-1,0, c, txc[6],txc[7]),
video::S3DVertex(min.X,min.Y,max.Z, 0,-1,0, c, txc[4],txc[7]),
// right
video::S3DVertex(max.X,max.Y,min.Z, 1,0,0, c, txc[ 8],txc[9]),
video::S3DVertex(max.X,max.Y,max.Z, 1,0,0, c, txc[10],txc[9]),
video::S3DVertex(max.X,min.Y,max.Z, 1,0,0, c, txc[10],txc[11]),
video::S3DVertex(max.X,min.Y,min.Z, 1,0,0, c, txc[ 8],txc[11]),
// left
video::S3DVertex(min.X,max.Y,max.Z, -1,0,0, c, txc[12],txc[13]),
video::S3DVertex(min.X,max.Y,min.Z, -1,0,0, c, txc[14],txc[13]),
video::S3DVertex(min.X,min.Y,min.Z, -1,0,0, c, txc[14],txc[15]),
video::S3DVertex(min.X,min.Y,max.Z, -1,0,0, c, txc[12],txc[15]),
// back
video::S3DVertex(max.X,max.Y,max.Z, 0,0,1, c, txc[16],txc[17]),
video::S3DVertex(min.X,max.Y,max.Z, 0,0,1, c, txc[18],txc[17]),
video::S3DVertex(min.X,min.Y,max.Z, 0,0,1, c, txc[18],txc[19]),
video::S3DVertex(max.X,min.Y,max.Z, 0,0,1, c, txc[16],txc[19]),
// front
video::S3DVertex(min.X,max.Y,min.Z, 0,0,-1, c, txc[20],txc[21]),
video::S3DVertex(max.X,max.Y,min.Z, 0,0,-1, c, txc[22],txc[21]),
video::S3DVertex(max.X,min.Y,min.Z, 0,0,-1, c, txc[22],txc[23]),
video::S3DVertex(min.X,min.Y,min.Z, 0,0,-1, c, txc[20],txc[23]),
};
u16 indices[] = {0,1,2,2,3,0};
for(u16 j = 0; j < 24; j += 4)
{
scene::IMeshBuffer *buf = dst_mesh->getMeshBuffer(j / 4);
buf->append(vertices + j, 4, indices, 6);
}
}
return dst_mesh;
}
struct vcache
{
core::array<u32> tris;
float score;
s16 cachepos;
u16 NumActiveTris;
};
struct tcache
{
u16 ind[3];
float score;
bool drawn;
};
const u16 cachesize = 32;
float FindVertexScore(vcache *v)
{
const float CacheDecayPower = 1.5f;
const float LastTriScore = 0.75f;
const float ValenceBoostScale = 2.0f;
const float ValenceBoostPower = 0.5f;
const float MaxSizeVertexCache = 32.0f;
if (v->NumActiveTris == 0)
{
// No tri needs this vertex!
return -1.0f;
}
float Score = 0.0f;
int CachePosition = v->cachepos;
if (CachePosition < 0)
{
// Vertex is not in FIFO cache - no score.
}
else
{
if (CachePosition < 3)
{
// This vertex was used in the last triangle,
// so it has a fixed score.
Score = LastTriScore;
}
else
{
// Points for being high in the cache.
const float Scaler = 1.0f / (MaxSizeVertexCache - 3);
Score = 1.0f - (CachePosition - 3) * Scaler;
Score = powf(Score, CacheDecayPower);
}
}
// Bonus points for having a low number of tris still to
// use the vert, so we get rid of lone verts quickly.
float ValenceBoost = powf(v->NumActiveTris,
-ValenceBoostPower);
Score += ValenceBoostScale * ValenceBoost;
return Score;
}
/*
A specialized LRU cache for the Forsyth algorithm.
*/
class f_lru
{
public:
f_lru(vcache *v, tcache *t): vc(v), tc(t)
{
for (u16 i = 0; i < cachesize; i++)
{
cache[i] = -1;
}
}
// Adds this vertex index and returns the highest-scoring triangle index
u32 add(u16 vert, bool updatetris = false)
{
bool found = false;
// Mark existing pos as empty
for (u16 i = 0; i < cachesize; i++)
{
if (cache[i] == vert)
{
// Move everything down
for (u16 j = i; j; j--)
{
cache[j] = cache[j - 1];
}
found = true;
break;
}
}
if (!found)
{
if (cache[cachesize-1] != -1)
vc[cache[cachesize-1]].cachepos = -1;
// Move everything down
for (u16 i = cachesize - 1; i; i--)
{
cache[i] = cache[i - 1];
}
}
cache[0] = vert;
u32 highest = 0;
float hiscore = 0;
if (updatetris)
{
// Update cache positions
for (u16 i = 0; i < cachesize; i++)
{
if (cache[i] == -1)
break;
vc[cache[i]].cachepos = i;
vc[cache[i]].score = FindVertexScore(&vc[cache[i]]);
}
// Update triangle scores
for (u16 i = 0; i < cachesize; i++)
{
if (cache[i] == -1)
break;
const u16 trisize = vc[cache[i]].tris.size();
for (u16 t = 0; t < trisize; t++)
{
tcache *tri = &tc[vc[cache[i]].tris[t]];
tri->score =
vc[tri->ind[0]].score +
vc[tri->ind[1]].score +
vc[tri->ind[2]].score;
if (tri->score > hiscore)
{
hiscore = tri->score;
highest = vc[cache[i]].tris[t];
}
}
}
}
return highest;
}
private:
s32 cache[cachesize];
vcache *vc;
tcache *tc;
};
/**
Vertex cache optimization according to the Forsyth paper:
http://home.comcast.net/~tom_forsyth/papers/fast_vert_cache_opt.html
The function is thread-safe (read: you can optimize several meshes in different threads)
\param mesh Source mesh for the operation. */
scene::IMesh* createForsythOptimizedMesh(const scene::IMesh *mesh)
{
if (!mesh)
return 0;
scene::SMesh *newmesh = new scene::SMesh();
newmesh->BoundingBox = mesh->getBoundingBox();
const u32 mbcount = mesh->getMeshBufferCount();
for (u32 b = 0; b < mbcount; ++b)
{
const scene::IMeshBuffer *mb = mesh->getMeshBuffer(b);
if (mb->getIndexType() != video::EIT_16BIT)
{
//os::Printer::log("Cannot optimize a mesh with 32bit indices", ELL_ERROR);
newmesh->drop();
return 0;
}
const u32 icount = mb->getIndexCount();
const u32 tcount = icount / 3;
const u32 vcount = mb->getVertexCount();
const u16 *ind = mb->getIndices();
vcache *vc = new vcache[vcount];
tcache *tc = new tcache[tcount];
f_lru lru(vc, tc);
// init
for (u16 i = 0; i < vcount; i++)
{
vc[i].score = 0;
vc[i].cachepos = -1;
vc[i].NumActiveTris = 0;
}
// First pass: count how many times a vert is used
for (u32 i = 0; i < icount; i += 3)
{
vc[ind[i]].NumActiveTris++;
vc[ind[i + 1]].NumActiveTris++;
vc[ind[i + 2]].NumActiveTris++;
const u32 tri_ind = i/3;
tc[tri_ind].ind[0] = ind[i];
tc[tri_ind].ind[1] = ind[i + 1];
tc[tri_ind].ind[2] = ind[i + 2];
}
// Second pass: list of each triangle
for (u32 i = 0; i < tcount; i++)
{
vc[tc[i].ind[0]].tris.push_back(i);
vc[tc[i].ind[1]].tris.push_back(i);
vc[tc[i].ind[2]].tris.push_back(i);
tc[i].drawn = false;
}
// Give initial scores
for (u16 i = 0; i < vcount; i++)
{
vc[i].score = FindVertexScore(&vc[i]);
}
for (u32 i = 0; i < tcount; i++)
{
tc[i].score =
vc[tc[i].ind[0]].score +
vc[tc[i].ind[1]].score +
vc[tc[i].ind[2]].score;
}
switch(mb->getVertexType())
{
case video::EVT_STANDARD:
{
video::S3DVertex *v = (video::S3DVertex *) mb->getVertices();
scene::SMeshBuffer *buf = new scene::SMeshBuffer();
buf->Material = mb->getMaterial();
buf->Vertices.reallocate(vcount);
buf->Indices.reallocate(icount);
core::map<const video::S3DVertex, const u16> sind; // search index for fast operation
typedef core::map<const video::S3DVertex, const u16>::Node snode;
// Main algorithm
u32 highest = 0;
u32 drawcalls = 0;
for (;;)
{
if (tc[highest].drawn)
{
bool found = false;
float hiscore = 0;
for (u32 t = 0; t < tcount; t++)
{
if (!tc[t].drawn)
{
if (tc[t].score > hiscore)
{
highest = t;
hiscore = tc[t].score;
found = true;
}
}
}
if (!found)
break;
}
// Output the best triangle
u16 newind = buf->Vertices.size();
snode *s = sind.find(v[tc[highest].ind[0]]);
if (!s)
{
buf->Vertices.push_back(v[tc[highest].ind[0]]);
buf->Indices.push_back(newind);
sind.insert(v[tc[highest].ind[0]], newind);
newind++;
}
else
{
buf->Indices.push_back(s->getValue());
}
s = sind.find(v[tc[highest].ind[1]]);
if (!s)
{
buf->Vertices.push_back(v[tc[highest].ind[1]]);
buf->Indices.push_back(newind);
sind.insert(v[tc[highest].ind[1]], newind);
newind++;
}
else
{
buf->Indices.push_back(s->getValue());
}
s = sind.find(v[tc[highest].ind[2]]);
if (!s)
{
buf->Vertices.push_back(v[tc[highest].ind[2]]);
buf->Indices.push_back(newind);
sind.insert(v[tc[highest].ind[2]], newind);
}
else
{
buf->Indices.push_back(s->getValue());
}
vc[tc[highest].ind[0]].NumActiveTris--;
vc[tc[highest].ind[1]].NumActiveTris--;
vc[tc[highest].ind[2]].NumActiveTris--;
tc[highest].drawn = true;
for (u16 j = 0; j < 3; j++)
{
vcache *vert = &vc[tc[highest].ind[j]];
for (u16 t = 0; t < vert->tris.size(); t++)
{
if (highest == vert->tris[t])
{
vert->tris.erase(t);
break;
}
}
}
lru.add(tc[highest].ind[0]);
lru.add(tc[highest].ind[1]);
highest = lru.add(tc[highest].ind[2], true);
drawcalls++;
}
buf->setBoundingBox(mb->getBoundingBox());
newmesh->addMeshBuffer(buf);
buf->drop();
}
break;
case video::EVT_2TCOORDS:
{
video::S3DVertex2TCoords *v = (video::S3DVertex2TCoords *) mb->getVertices();
scene::SMeshBufferLightMap *buf = new scene::SMeshBufferLightMap();
buf->Material = mb->getMaterial();
buf->Vertices.reallocate(vcount);
buf->Indices.reallocate(icount);
core::map<const video::S3DVertex2TCoords, const u16> sind; // search index for fast operation
typedef core::map<const video::S3DVertex2TCoords, const u16>::Node snode;
// Main algorithm
u32 highest = 0;
u32 drawcalls = 0;
for (;;)
{
if (tc[highest].drawn)
{
bool found = false;
float hiscore = 0;
for (u32 t = 0; t < tcount; t++)
{
if (!tc[t].drawn)
{
if (tc[t].score > hiscore)
{
highest = t;
hiscore = tc[t].score;
found = true;
}
}
}
if (!found)
break;
}
// Output the best triangle
u16 newind = buf->Vertices.size();
snode *s = sind.find(v[tc[highest].ind[0]]);
if (!s)
{
buf->Vertices.push_back(v[tc[highest].ind[0]]);
buf->Indices.push_back(newind);
sind.insert(v[tc[highest].ind[0]], newind);
newind++;
}
else
{
buf->Indices.push_back(s->getValue());
}
s = sind.find(v[tc[highest].ind[1]]);
if (!s)
{
buf->Vertices.push_back(v[tc[highest].ind[1]]);
buf->Indices.push_back(newind);
sind.insert(v[tc[highest].ind[1]], newind);
newind++;
}
else
{
buf->Indices.push_back(s->getValue());
}
s = sind.find(v[tc[highest].ind[2]]);
if (!s)
{
buf->Vertices.push_back(v[tc[highest].ind[2]]);
buf->Indices.push_back(newind);
sind.insert(v[tc[highest].ind[2]], newind);
}
else
{
buf->Indices.push_back(s->getValue());
}
vc[tc[highest].ind[0]].NumActiveTris--;
vc[tc[highest].ind[1]].NumActiveTris--;
vc[tc[highest].ind[2]].NumActiveTris--;
tc[highest].drawn = true;
for (u16 j = 0; j < 3; j++)
{
vcache *vert = &vc[tc[highest].ind[j]];
for (u16 t = 0; t < vert->tris.size(); t++)
{
if (highest == vert->tris[t])
{
vert->tris.erase(t);
break;
}
}
}
lru.add(tc[highest].ind[0]);
lru.add(tc[highest].ind[1]);
highest = lru.add(tc[highest].ind[2]);
drawcalls++;
}
buf->setBoundingBox(mb->getBoundingBox());
newmesh->addMeshBuffer(buf);
buf->drop();
}
break;
case video::EVT_TANGENTS:
{
video::S3DVertexTangents *v = (video::S3DVertexTangents *) mb->getVertices();
scene::SMeshBufferTangents *buf = new scene::SMeshBufferTangents();
buf->Material = mb->getMaterial();
buf->Vertices.reallocate(vcount);
buf->Indices.reallocate(icount);
core::map<const video::S3DVertexTangents, const u16> sind; // search index for fast operation
typedef core::map<const video::S3DVertexTangents, const u16>::Node snode;
// Main algorithm
u32 highest = 0;
u32 drawcalls = 0;
for (;;)
{
if (tc[highest].drawn)
{
bool found = false;
float hiscore = 0;
for (u32 t = 0; t < tcount; t++)
{
if (!tc[t].drawn)
{
if (tc[t].score > hiscore)
{
highest = t;
hiscore = tc[t].score;
found = true;
}
}
}
if (!found)
break;
}
// Output the best triangle
u16 newind = buf->Vertices.size();
snode *s = sind.find(v[tc[highest].ind[0]]);
if (!s)
{
buf->Vertices.push_back(v[tc[highest].ind[0]]);
buf->Indices.push_back(newind);
sind.insert(v[tc[highest].ind[0]], newind);
newind++;
}
else
{
buf->Indices.push_back(s->getValue());
}
s = sind.find(v[tc[highest].ind[1]]);
if (!s)
{
buf->Vertices.push_back(v[tc[highest].ind[1]]);
buf->Indices.push_back(newind);
sind.insert(v[tc[highest].ind[1]], newind);
newind++;
}
else
{
buf->Indices.push_back(s->getValue());
}
s = sind.find(v[tc[highest].ind[2]]);
if (!s)
{
buf->Vertices.push_back(v[tc[highest].ind[2]]);
buf->Indices.push_back(newind);
sind.insert(v[tc[highest].ind[2]], newind);
}
else
{
buf->Indices.push_back(s->getValue());
}
vc[tc[highest].ind[0]].NumActiveTris--;
vc[tc[highest].ind[1]].NumActiveTris--;
vc[tc[highest].ind[2]].NumActiveTris--;
tc[highest].drawn = true;
for (u16 j = 0; j < 3; j++)
{
vcache *vert = &vc[tc[highest].ind[j]];
for (u16 t = 0; t < vert->tris.size(); t++)
{
if (highest == vert->tris[t])
{
vert->tris.erase(t);
break;
}
}
}
lru.add(tc[highest].ind[0]);
lru.add(tc[highest].ind[1]);
highest = lru.add(tc[highest].ind[2]);
drawcalls++;
}
buf->setBoundingBox(mb->getBoundingBox());
newmesh->addMeshBuffer(buf);
buf->drop();
}
break;
}
delete [] vc;
delete [] tc;
} // for each meshbuffer
return newmesh;
}