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I have one issue left with ASSIMP DIRECT X C++ ANIMATION WITH SKELETON.
for (UINT m = 0; m < currentMesh->mBones[k]->mNumWeights; m++) //verticer som påverkas
{
vertexVector[k].joints.x = currentMesh->mBones[k]->mWeights[m].mVertexId;
That code shows all vertices affected by a bone - k, inside an iteration.
All of these vertices must have the same vert ID since they are all affected by the same bone/joint.
The problem is, I need to make a list of every vertex and a list of every indice of a face, where I store position, UV, Normal etc.
The list that displays all of the vertices, is not in the same order obviously as the lists that displays all the vertices affected by each bone.
So how can I combine these lists?
"vertexVector"... etc is an example of a list with jointInfo that is corresponding to vertexID.
It has room for more places and another variable for the weight.
But that list doesn't work obviously.
What am I doing wrong with Assimp? Hope this was a clear post.
UPdate this is how i build the matrices: I don't know what is wrong.
void jointTransform(float
timeInSeconds, std::vector<DirectX::XMMATRIX>& transformM, aiAnimation*
ani, UINT nrOfJoints, std::vector<joints>& jointInfo, const aiScene*
scenePtr)
{
DirectX::XMMATRIX iD = DirectX::XMMatrixIdentity();
float ticksPerSecond = (float)ani->mTicksPerSecond;
if (ticksPerSecond == 0)
{
ticksPerSecond = 30;
}
float timeInTicks = timeInSeconds * ticksPerSecond;
float animationTime = fmod(timeInTicks, (float)ani->mDuration);
readNodeHeiarchy(animationTime, scenePtr->mRootNode, iD, jointInfo, ani,
scenePtr);
transformM.resize(nrOfJoints);
for (UINT i = 0; i < transformM.size(); i++)
{
transformM[i] = jointInfo[i].transformFinal;
}
}
void readNodeHeiarchy(float time, const aiNode* node, DirectX::XMMATRIX
parentMat, std::vector<joints>& jointInfo, aiAnimation* ani, const
aiScene* scenePtr)
{
std::string nodeNameString = node->mName.data;
//Skapa en parentTransform från noden. Som sedan skickas in som parent
matris, första gången är det identitetsmatrisen.
aiMatrix4x4 nodeTransform = node->mTransformation;
DirectX::XMMATRIX combined;
combined = DirectX::XMMatrixSet(nodeTransform.a1, nodeTransform.a2,
nodeTransform.a3, nodeTransform.a4,
nodeTransform.b1, nodeTransform.b2, nodeTransform.b3, nodeTransform.b4,
nodeTransform.c1, nodeTransform.c2, nodeTransform.c3, nodeTransform.c4,
nodeTransform.d1, nodeTransform.d2, nodeTransform.d3,
nodeTransform.d4);
const aiNodeAnim* joint = nullptr;
//Kolla om noden är ett ben.
for (UINT i = 0; i < ani->mNumChannels; i++)
{
if (nodeNameString == ani->mChannels[i]->mNodeName.data)
{
joint = ani->mChannels[i];
}
}
DirectX::XMMATRIX globalTransform = DirectX::XMMatrixIdentity();
//om den är ett ben så är joint inte längre nullptr, den blir det benet.
if (joint)
{
DirectX::XMMATRIX S;
DirectX::XMMATRIX R;
DirectX::XMMATRIX T;
//scale
aiVector3D scaleV;
calcLerpScale(scaleV, time, joint);
S = DirectX::XMMatrixScaling(scaleV.x, scaleV.y, scaleV.z);
//rotate
aiQuaternion rotationQ;
calcLerpRot(rotationQ, time, joint);
DirectX::XMVECTOR q;
q = DirectX::XMVectorSet(rotationQ.x, rotationQ.y, rotationQ.z,
rotationQ.w);
R = DirectX::XMMatrixRotationQuaternion(q);
//translate
aiVector3D transV;
calcLerpTrans(transV, time, joint);
T = DirectX::XMMatrixTranslation(transV.x, transV.y, transV.z);
combined = S * R * T;
globalTransform = combined * parentMat;
}
//DirectX::XMMATRIX globalTransform = combined * parentMat;
//if (jointInfo[jointInfo.size() - 1].name.C_Str() != nodeNameString)
//{
for (UINT i = 0; i < jointInfo.size(); i++)
{
if (jointInfo[i].name.C_Str() == nodeNameString)
{
OutputDebugStringA("\n");
OutputDebugStringA(jointInfo[i].name.C_Str());
OutputDebugStringA("\n");
aiMatrix4x4 off = jointInfo[i].offsetM;
DirectX::XMMATRIX offset;
offset = DirectX::XMMatrixSet(off.a1, off.a2, off.a3, off.a4,
off.b1, off.b2, off.b3, off.b4,
off.c1, off.c2, off.c3, off.c4,
off.d1, off.d2, off.d3, off.d4);
DirectX::XMMATRIX rootMInv;
aiMatrix4x4 rootInv = scenePtr->mRootNode-
>mTransformation.Inverse();
rootMInv = DirectX::XMMatrixSet(rootInv.a1, rootInv.a2,
rootInv.a3, rootInv.a4,
rootInv.b1, rootInv.b2, rootInv.b3, rootInv.b4,
rootInv.c1, rootInv.c2, rootInv.c3, rootInv.c4,
rootInv.d1, rootInv.d2, rootInv.d3, rootInv.d4);
jointInfo[i].transformFinal = offset * globalTransform *
rootMInv;
break;
}
}
//}
for (UINT i = 0; i < node->mNumChildren; i++)
{
readNodeHeiarchy(time, node->mChildren[i], globalTransform, jointInfo,
ani, scenePtr);
}
}
void calcLerpScale(aiVector3D& scale, float aniTime, const aiNodeAnim*
joint)
{
if (joint->mNumScalingKeys == 1)
{
scale = joint->mScalingKeys[0].mValue;
return;
}
UINT scaleInd = findIndexS(aniTime, joint);
UINT nextScale = scaleInd + 1;
assert(nextScale < joint->mNumScalingKeys);
float deltaTime = (float)joint->mScalingKeys[nextScale].mTime -
(float)joint->mScalingKeys[scaleInd].mTime;
float factor = (aniTime - (float)joint->mScalingKeys[scaleInd].mTime) /
deltaTime;
assert(factor >= 0.0f && factor <= 1.0f);
const aiVector3D& startScaleV = joint->mScalingKeys[scaleInd].mValue;
const aiVector3D& endScaleV = joint->mScalingKeys[nextScale].mValue;
//interpolate
aiVector3D Delta = endScaleV - startScaleV; // längden
scale = startScaleV + (factor * Delta); //gå ett antal steg beroende på
faktorn mellan start och slut.
scale.Normalize();
}
void calcLerpRot(aiQuaternion& rotation, float aniTime, const aiNodeAnim*
joint)
{
if (joint->mNumRotationKeys == 1)
{
rotation = joint->mRotationKeys[0].mValue;
return;
}
UINT rotIndex = findIndexRot(aniTime, joint);
UINT nextRot = (rotIndex + 1);
assert(nextRot < joint->mNumRotationKeys);
float deltaTime = (float)joint->mRotationKeys[nextRot].mTime -
(float)joint->mRotationKeys[rotIndex].mTime;
float factor = (aniTime - (float)joint->mRotationKeys[rotIndex].mTime) /
deltaTime;
assert(factor >= 0.0f && factor <= 1.0f);
const aiQuaternion& StartRotationQ = joint->mRotationKeys[rotIndex].mValue;
const aiQuaternion& EndRotationQ = joint->mRotationKeys[nextRot].mValue;
aiQuaternion::Interpolate(rotation, StartRotationQ, EndRotationQ, factor);
rotation.Normalize();
}
void calcLerpTrans(aiVector3D& translation, float aniTime, const
aiNodeAnim*
joint)
{
if (joint->mNumPositionKeys == 1)
{
translation = joint->mPositionKeys[0].mValue;
return;
}
UINT transIndex = findIndexT(aniTime, joint);
UINT nextTrans = (transIndex + 1);
assert(nextTrans < joint->mNumPositionKeys);
float deltaTime = (float)joint->mPositionKeys[nextTrans].mTime -
(float)joint->mPositionKeys[transIndex].mTime;
float factor = (aniTime - (float)joint->mPositionKeys[transIndex].mTime) /
deltaTime;
assert(factor >= 0.0f && factor <= 1.0f);
const aiVector3D& startTransV = joint->mPositionKeys[transIndex].mValue;
const aiVector3D& endTransV = joint->mPositionKeys[nextTrans].mValue;
//interpolate
aiVector3D Delta = endTransV - startTransV;
translation = startTransV + (factor * Delta);
translation.Normalize();
}
UINT findIndexRot(float aniTime, const aiNodeAnim* joint)
{
assert(joint->mNumRotationKeys > 0);
for (UINT i = 0; i < joint->mNumRotationKeys - 1; i++)
{
if (aniTime < (float)joint->mRotationKeys[i + 1].mTime)
{
return i;
}
}
assert(0);
}
}
Not sure what you mean by "All of these vertices must have the same vert ID" - the vertex id's of the k:th bone, according to mBones[k]->mWeights[..].mVertexId, are indices to vertices influenced by this bone, and they are going to be different (otherwise there would be either redundancy of conflict).
You probably want to have bone indices and bone weights as part of the vertex definition for easy handling in a shader. Something like
struct vertex (
vec3 pos;
vec3 normal;
float bone_weights[N]; // weights of bones influencing this vertex
unsigned bone_indices[N]; // indices of bones influencing this vertex
}
std::vector<vertex> mesh_vertices;
Where N is the maximum number of influence bones per vertex. A common value is four, but this depends on the mesh your are importing.
Based on your example, a rough draft could be something like this:
// k:th bone of bones in currentMesh
for (UINT m = 0; m < currentMesh->mBones[k]->mNumWeights; m++)
{
float bone_weight = currentMesh->mBones[k]->mWeights[m].mWeight;
unsigned vertex_index = currentMesh->mBones[k]->mWeights[m].mVertexId;
mesh_vertices[vertex_index].bone_weights[m] = bone_weight;
mesh_vertices[vertex_index].bone_indices[m] = k;
}
Here we've assumed that mNumWeights = N, but this needs to checked, as mentioned.
I want to a recycler view like below image. Means I want to max height and width of middle recycler view item in a horizontal recycler view.
I found a solution from a link, you may follow it accordingly.
public class CenterZoomLayoutManager extends LinearLayoutManager {
private final float mShrinkAmount = 0.15f;
private final float mShrinkDistance = 0.9f;
public CenterZoomLayoutManager(Context context) {
super(context);
}
public CenterZoomLayoutManager(Context context, int orientation, boolean reverseLayout) {
super(context, orientation, reverseLayout);
}
#Override
public int scrollVerticallyBy(int dy, RecyclerView.Recycler recycler, RecyclerView.State state) {
int orientation = getOrientation();
if (orientation == VERTICAL) {
int scrolled = super.scrollVerticallyBy(dy, recycler, state);
float midpoint = getHeight() / 2.f;
float d0 = 0.f;
float d1 = mShrinkDistance * midpoint;
float s0 = 1.f;
float s1 = 1.f - mShrinkAmount;
for (int i = 0; i < getChildCount(); i++) {
View child = getChildAt(i);
float childMidpoint =
(getDecoratedBottom(child) + getDecoratedTop(child)) / 2.f;
float d = Math.min(d1, Math.abs(midpoint - childMidpoint));
float scale = s0 + (s1 - s0) * (d - d0) / (d1 - d0);
child.setScaleX(scale);
child.setScaleY(scale);
}
return scrolled;
} else {
return 0;
}
}
#Override
public int scrollHorizontallyBy(int dx, RecyclerView.Recycler recycler, RecyclerView.State state) {
int orientation = getOrientation();
if (orientation == HORIZONTAL) {
int scrolled = super.scrollHorizontallyBy(dx, recycler, state);
float midpoint = getWidth() / 2.f;
float d0 = 0.f;
float d1 = mShrinkDistance * midpoint;
float s0 = 1.f;
float s1 = 1.f - mShrinkAmount;
for (int i = 0; i < getChildCount(); i++) {
View child = getChildAt(i);
float childMidpoint =
(getDecoratedRight(child) + getDecoratedLeft(child)) / 2.f;
float d = Math.min(d1, Math.abs(midpoint - childMidpoint));
float scale = s0 + (s1 - s0) * (d - d0) / (d1 - d0);
child.setScaleX(scale);
child.setScaleY(scale);
}
return scrolled;
} else {
return 0;
}
}
}
I currently use CGAL to generate 2D Delaunay triangulation.One of the mesh control parameter is the maximum length of the triangle edge. The examples suggests that this parameter is a constant. I would like to know how this parameter be made function of some thing else, for example spatial location.
I think Delaunay meshing with variable density is not directly supported by CGAL although you could mesh your regions independently. Alternatively you may have a look at: http://www.geom.at/advanced-mesh-generation/ where I have implemented that as a callback function.
It doesn't look like CGAL provides an example of this but they machinery is all there. The details get a little complicated since the objects that control if triangles need to be refined also have to understand the priority under which triangles get refined.
To do this, I copied Delaunay_mesh_size_criteria_2 to create a new class (Delaunay_mesh_user_criteria_2) that has a spatially varying sizing field. Buried in the class is a function (user_sizing_field) that can be implemented with a varying size field based on location. The code below compares the size of the longest edge of the triangle to the minimum of the sizing field at the three vertices, but you could use a size at the barycenter or circumcenter or even send the entire triangle to the sizing function if you have a good way to compute the smallest allowable size on the triangle altogether.
This is a starting point, although a better solution would,
refactor some things to avoid so much duplication with with existing Delaunay_mesh_size_criteria,
allow the user to pass in the sizing function as an argument to the criteria object, and
be shipped with CGAL.
template <class CDT>
class Delaunay_mesh_user_criteria_2 :
public virtual Delaunay_mesh_criteria_2<CDT>
{
protected:
typedef typename CDT::Geom_traits Geom_traits;
double sizebound;
public:
typedef Delaunay_mesh_criteria_2<CDT> Base;
Delaunay_mesh_user_criteria_2(const double aspect_bound = 0.125,
const Geom_traits& traits = Geom_traits())
: Base(aspect_bound, traits){}
// first: squared_minimum_sine
// second: size
struct Quality : public std::pair<double, double>
{
typedef std::pair<double, double> Base;
Quality() : Base() {};
Quality(double _sine, double _size) : Base(_sine, _size) {}
const double& size() const { return second; }
const double& sine() const { return first; }
// q1<q2 means q1 is prioritised over q2
// ( q1 == *this, q2 == q )
bool operator<(const Quality& q) const
{
if( size() > 1 )
if( q.size() > 1 )
return ( size() > q.size() );
else
return true; // *this is big but not q
else
if( q.size() > 1 )
return false; // q is big but not *this
return( sine() < q.sine() );
}
std::ostream& operator<<(std::ostream& out) const
{
return out << "(size=" << size()
<< ", sine=" << sine() << ")";
}
};
class Is_bad: public Base::Is_bad
{
public:
typedef typename Base::Is_bad::Point_2 Point_2;
Is_bad(const double aspect_bound,
const Geom_traits& traits)
: Base::Is_bad(aspect_bound, traits) {}
Mesh_2::Face_badness operator()(const Quality q) const
{
if( q.size() > 1 )
return Mesh_2::IMPERATIVELY_BAD;
if( q.sine() < this->B )
return Mesh_2::BAD;
else
return Mesh_2::NOT_BAD;
}
double user_sizing_function(const Point_2 p) const
{
// IMPLEMENT YOUR CUSTOM SIZING FUNCTION HERE.
// BUT MAKE SURE THIS RETURNS SOMETHING LARGER
// THAN ZERO TO ALLOW THE ALGORITHM TO TERMINATE
return std::abs(p.x()) + .025;
}
Mesh_2::Face_badness operator()(const typename CDT::Face_handle& fh,
Quality& q) const
{
typedef typename CDT::Geom_traits Geom_traits;
typedef typename Geom_traits::Compute_area_2 Compute_area_2;
typedef typename Geom_traits::Compute_squared_distance_2 Compute_squared_distance_2;
Geom_traits traits; /** #warning traits with data!! */
Compute_squared_distance_2 squared_distance =
traits.compute_squared_distance_2_object();
const Point_2& pa = fh->vertex(0)->point();
const Point_2& pb = fh->vertex(1)->point();
const Point_2& pc = fh->vertex(2)->point();
double size_bound = std::min(std::min(user_sizing_function(pa),
user_sizing_function(pb)),
user_sizing_function(pc));
double
a = CGAL::to_double(squared_distance(pb, pc)),
b = CGAL::to_double(squared_distance(pc, pa)),
c = CGAL::to_double(squared_distance(pa, pb));
double max_sq_length; // squared max edge length
double second_max_sq_length;
if(a<b)
{
if(b<c) {
max_sq_length = c;
second_max_sq_length = b;
}
else { // c<=b
max_sq_length = b;
second_max_sq_length = ( a < c ? c : a );
}
}
else // b<=a
{
if(a<c) {
max_sq_length = c;
second_max_sq_length = a;
}
else { // c<=a
max_sq_length = a;
second_max_sq_length = ( b < c ? c : b );
}
}
q.second = 0;
q.second = max_sq_length / (size_bound*size_bound);
// normalized by size bound to deal
// with size field
if( q.size() > 1 )
{
q.first = 1; // (do not compute sine)
return Mesh_2::IMPERATIVELY_BAD;
}
Compute_area_2 area_2 = traits.compute_area_2_object();
double area = 2*CGAL::to_double(area_2(pa, pb, pc));
q.first = (area * area) / (max_sq_length * second_max_sq_length); // (sine)
if( q.sine() < this->B )
return Mesh_2::BAD;
else
return Mesh_2::NOT_BAD;
}
};
Is_bad is_bad_object() const
{ return Is_bad(this->bound(), this->traits /* from the bad class */); }
};
I am also interested for variable mesh criteria on the domaine with CGAL. I have found an alternative many years ago : https://www.cs.cmu.edu/~quake/triangle.html
But i am still interested to do the same things with CGAL ... I don't know if it is possible ...
When I try to caculate sinh−1(x) using functions:
double asinh_recursion(double buf, double increment, double input_var, unsigned long item_count) {
if (fabs(increment) < 1E-5) {
return buf;
}
return asinh_recursion(buf + increment, increment * (-1) * (2 * item_count - 1) * (2 * item_count -1) / (2 * item_count + 1) / 2 / item_count * input_var, input_var, item_count + 1);
}
double asinh(double x) {
if (!(fabs(x) < 1.0)) {
printf("error asinh():wrong param x(fabs(x) > 1.0)");
return -1.0;
}
return asinh_recursion(0.0, x, x * x, 1);
}
it seem works.
but when I try to use block and Y-Combinator to do it:
typedef void * (^YCBlock)(void *);
YCBlock Y;
double asinh_with_block(double x) {
if (!(fabs(x) < 1.0)) {
printf("error asinh():wrong param x(fabs(x) > 1.0)");
return -1.0;
}
Y= (YCBlock) ^ (YCBlock f) {
return (YCBlock) ^ (YCBlock g) {
return g(g);
}(
(YCBlock) ^ (YCBlock h) {
return f(^ (void * x) { return ((YCBlock)h(h))(x); });
}
);
};
typedef double (^ RECUR_BLK_TYPE)(double, double, unsigned long);
RECUR_BLK_TYPE recur_block = Y(^(RECUR_BLK_TYPE recur_block){
return Block_copy(^ double (double buf, double increment, unsigned long item_count){
if (item_count < 4) {
printf("param:%lf,%lf,%lu\n", buf, increment, item_count);
}
if (fabs(increment) < 1E-5) {
return buf;
}
buf = buf + increment;
increment = increment * (-1) * (2 * item_count - 1) * (2 * item_count -1) / (2 * item_count + 1) / 2 / item_count * (x * x);
++item_count;
if (item_count < 4) {
printf("\tbuf:%lf\n", buf);
}
return recur_block(buf, increment, item_count);
});
});
double ret = recur_block(0, x, 1);
Block_release(recur_block);
Block_release(Y);
return ret;
}
but it works strangely in the output(x=0.5):
param:0.000000,0.500000,1
buf:0.500000
param:0.500000,-0.020833,2
buf:0.479167
param:0.500000,0.002344,3
...
asinh_with_block(0.500000):0.500000
it seem like that in the block, at some time,when I pass buf=0.479167, next time when I print it, it is still 0.500000.
I wanna to find why it works like this, maybe I wrote some wrong code at somewhere...
The problem is that your Y combinator is only made to work with an underlying function that takes one void * parameter and returns a void *. You can see that in the line:
return f(^ (void * x) { return ((YCBlock)h(h))(x); });
The block in there that takes x (one argument) and passed the x to another thing as one argument. For it to work with a recursive function of multiple arguments, this function must take those multiple arguments and pass them all on (of course, the types all need to be right too, because different types have different sizes, and the ABI for passing and returning things of different types is different). So you will need a different Y combinator for each function signature.
You have a recursive function that takes three parameters (two doubles and an unsigned long) and returns a double. You can (minimally) make it work by changing the relevant block in the Y combinator and coercing it from the wrong type to the right type:
return f(^ (double buf, double increment, unsigned long item_count) {
return ((RECUR_BLK_TYPE)((YCBlock)h(h)))(buf, increment, item_count);
});
But to really make it clean with correct type safety without this unsafe casting would require you to carefully set up the types. Something like this:
typedef double (^Func)(double, double, unsigned long);
typedef Func (^FuncFunc)(Func);
typedef Func (^RecursiveFunc)(void *);
typedef Func (^YCBlock)(FuncFunc);
Y = ^(FuncFunc f) {
return ^(RecursiveFunc g) {
return g(g);
}(
^(void *temp) {
RecursiveFunc h = temp; // trick to hide the recursive typing
return f(^(double buf, double increment, unsigned long item_count) {
return h(h)(buf, increment, item_count);
});
}
);
};
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Convert decimal to fraction in Objective-C?
I'm trying to make an simple app for converting decimal form to fraction form. The decimal value is set to a UISlider´s value but how should I get the fraction in fraction form? Should I declare it with double or float and how should I tell the app to print it out in fraction form?
You want to return a fractional approximation from a real number? e.g. 0.3333 ~ "1/3". You could try experimenting with this:
#import <Foundation/Foundation.h>
char out[20];
static char *fractApprox(double r, long d) {
double atof();
int atoi();
void exit();
long m[2][2];
double x, startx;
long maxden;
long ai;
startx = x = r;
maxden = d;
/* initialize matrix */
m[0][0] = m[1][1] = 1;
m[0][1] = m[1][0] = 0;
/* loop finding terms until denom gets too big */
while (m[1][0] * ( ai = (long)x ) + m[1][1] <= maxden) {
long t;
t = m[0][0] * ai + m[0][1];
m[0][1] = m[0][0];
m[0][0] = t;
t = m[1][0] * ai + m[1][1];
m[1][1] = m[1][0];
m[1][0] = t;
if(x==(double)ai) break; // AF: division by zero
x = 1/(x - (double) ai);
if(x>(double)0x7FFFFFFF) break; // AF: representation failure
}
ai = (maxden - m[1][1]) / m[1][0];
m[0][0] = m[0][0] * ai + m[0][1];
m[1][0] = m[1][0] * ai + m[1][1];
sprintf(out, "%ld/%ld",m[0][0],m[1][0]);
return out;
}
int main(int argc, const char * argv[])
{
#autoreleasepool {
printf("%s",fractApprox(0.342343, 999));
}
return 0;
}
Prints 329/961 to the console.
Credits to David Eppstein, UC Irvine for the algorithm in C
What you need to convert a decimal to fraction is GCD. For example:
0.535
0.535 => 535/1000
GCD(535, 1000) => 5
(535/5) / (1000/5) => 107/200.