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#include "ofxThreadedImageLoader.h"
#include <sstream>
ofxThreadedImageLoader::ofxThreadedImageLoader(){
nextID = 0;
ofAddListener(ofEvents().update, this, &ofxThreadedImageLoader::update);
ofAddListener(ofURLResponseEvent(),this,&ofxThreadedImageLoader::urlResponse);
startThread();
lastUpdate = 0;
}
ofxThreadedImageLoader::~ofxThreadedImageLoader(){
images_to_load_from_disk.close();
images_to_update.close();
waitForThread(true);
ofRemoveListener(ofEvents().update, this, &ofxThreadedImageLoader::update);
ofRemoveListener(ofURLResponseEvent(),this,&ofxThreadedImageLoader::urlResponse);
}
// Load an image from disk.
//--------------------------------------------------------------
void ofxThreadedImageLoader::loadFromDisk(ofImage& image, string filename) {
nextID++;
ofImageLoaderEntry entry(image);
entry.filename = filename;
entry.image->setUseTexture(false);
entry.name = filename;
// bDoneLoading = false;
images_to_load_from_disk.send(entry);
}
// Load an url asynchronously from an url.
//--------------------------------------------------------------
void ofxThreadedImageLoader::loadFromURL(ofImage& image, string url) {
nextID++;
ofImageLoaderEntry entry(image);
entry.url = url;
entry.image->setUseTexture(false);
entry.name = "image" + ofToString(nextID);
images_async_loading[entry.name] = entry;
ofLoadURLAsync(entry.url, entry.name);
}
// Reads from the queue and loads new images.
//--------------------------------------------------------------
void ofxThreadedImageLoader::threadedFunction() {
thread.setName("ofxThreadedImageLoader " + thread.name());
ofImageLoaderEntry entry;
while( images_to_load_from_disk.receive(entry) ) {
if(entry.image->load(entry.filename) ) {
images_to_update.send(entry);
bDoneLoading = false;
}else{
ofLogError("ofxThreadedImageLoader") << "couldn't load file: \"" << entry.filename << "\"";
}
}
// bDoneLoading = true;
// ofLogVerbose("ofxThreadedImageLoader") << "finishing thread on closed queue";
ofLog() << "finishing thread on closed queue";
}
// When we receive an url response this method is called;
// The loaded image is removed from the async_queue and added to the
// update queue. The update queue is used to update the texture.
//--------------------------------------------------------------
void ofxThreadedImageLoader::urlResponse(ofHttpResponse & response) {
// this happens in the update thread so no need to lock to access
// images_async_loading
entry_iterator it = images_async_loading.find(response.request.name);
if(response.status == 200) {
if(it != images_async_loading.end()) {
it->second.image->load(response.data);
images_to_update.send(it->second);
}
}else{
// log error.
ofLogError("ofxThreadedImageLoader") << "couldn't load url, response status: " << response.status;
ofRemoveURLRequest(response.request.getID());
}
// remove the entry from the queue
if(it != images_async_loading.end()) {
images_async_loading.erase(it);
}
}
// Check the update queue and update the texture
//--------------------------------------------------------------
void ofxThreadedImageLoader::update(ofEventArgs & a){
// Load 1 image per update so we don't block the gl thread for too long
ofImageLoaderEntry entry;
if (images_to_update.tryReceive(entry)) {
entry.image->setUseTexture(true);
entry.image->update();
}else{
bDoneLoading = true;
}
}
#pragma once
#include "ofThread.h"
#include "ofImage.h"
#include "ofURLFileLoader.h"
#include "ofTypes.h"
#include "ofThreadChannel.h"
using namespace std;
class ofxThreadedImageLoader : public ofThread {
public:
ofxThreadedImageLoader();
~ofxThreadedImageLoader();
void loadFromDisk(ofImage& image, string file);
void loadFromURL(ofImage& image, string url);
bool bDoneLoading;
private:
void update(ofEventArgs & a);
virtual void threadedFunction();
void urlResponse(ofHttpResponse & response);
// Entry to load.
struct ofImageLoaderEntry {
ofImageLoaderEntry() {
image = NULL;
}
ofImageLoaderEntry(ofImage & pImage) {
image = &pImage;
}
ofImage* image;
string filename;
string url;
string name;
};
typedef map<string, ofImageLoaderEntry>::iterator entry_iterator;
int nextID;
int lastUpdate;
map<string,ofImageLoaderEntry> images_async_loading; // keeps track of images which are loading async
ofThreadChannel<ofImageLoaderEntry> images_to_load_from_disk;
ofThreadChannel<ofImageLoaderEntry> images_to_update;
};
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