Apply bitmap mask to image on html5 canvas -

-

good morning, have canvas background image, need put image on , apply mask on have transparency. here can find link sample of final result need. can me?

enter image description here

imagecontext.drawimage(mask, 0, 0, width, height); imagecontext.globalcompositeoperation = 'source-atop'; imagecontext.drawimage(img, 0, 0);

http://codepo8.github.io/canvas-masking/


Comments

Post a Comment

Popular posts from this blog

c++ - list<myClass<int> * > sort -

-
i cannot sort list contains pointers objects of template class. template class node{ public: node(void){} node(t choice, vector<t> & data); node(t choice, vector<t> & data, player p, int level, int pos, node<t> *pred, side); void addnodes(void); static list<node<t> * > nodes; friend class mybinomialtree<node<t>, t>; bool sorter(const node<t> * lhs, const node<t> * rhs);// * &lhs doesn't work private: node<t> * left; node<t> * right; t chosen_; vector<t> data_; bool isleaf; //... }; outside class: template<class t> bool node<t>::sorter(const node<t> * lhs, const node<t> * rhs){ if((*lhs).level_==(*rhs).level_){ return (*lhs).pos_<(*rhs).pos_; }else{ return (*lhs).level_<(*rhs).level_; } } and want sort before print, have template<class t> void node<t>::print(void){ ...
Read more

c - Defining floating point constants, how many digits are useful? -

-
when define constants in c cannot accurately represented in decimal system, example π , how many digits taken account compiler creating float or double in memory? for example: /* overkill? */ const float pi_f = 3.1415926535897932384626433832795f; /* few digits? */ const double pi_d = 3.14159; assuming ieee 754 standard floating point numbers , commonplace nowadays, 7.22 digits of accuracy float , 15.95 double , aim 7 digits after decimal point float π constant , 15 double on safe side. 128-bit long double gives 34.02 precision, 33 positions after decimal point in π.(*) however, excess precision won't hurt, compiler cut off. (*) note long double quite not ieee format; x86-32 typically has 80-bit, not 128-bit, long double . in msvc, it's apparently synonym double , 64-bit.
Read more

C# Apple Bonjour - how to monitor service records within Windows -

-
i'm using apples bonjour pronounce client information. class bonjourexample { private bonjour.dnssdeventmanager m_eventmanager;; private bonjour.dnssdservice m_service; private bonjour.dnssdservice m_browser; private bonjour.dnssdservice m_resolver; private init() { m_service = new dnssdservice(); m_eventmanager = new dnssdeventmanager(); m_eventmanager.servicefound += new _idnssdevents_servicefoundeventhandler(this.servicefound); m_eventmanager.servicelost += new _idnssdevents_servicelosteventhandler(this.servicelost); m_eventmanager.serviceresolved += new _idnssdevents_serviceresolvedeventhandler(this.serviceresolved); m_eventmanager.queryrecordanswered += new _idnssdevents_queryrecordansweredeventhandler(this.queryanswered); m_eventmanager.operationfailed += new _idnssdevents_operationfailedeventhandler(this.operationfailed); m_bonjourbrowser = m_bonjourservice.b...
Read more