Handle<Value>
DynamicPngStack::PngEncodeAsync(const Arguments &args)
{
HandleScope scope;
if (args.Length() != 1)
return VException("One argument required - callback function.");
if (!args[0]->IsFunction())
return VException("First argument must be a function.");
Local<Function> callback = Local<Function>::Cast(args[0]);
DynamicPngStack *png = ObjectWrap::Unwrap<DynamicPngStack>(args.This());
encode_request *enc_req = (encode_request *)malloc(sizeof(*enc_req));
if (!enc_req)
return VException("malloc in DynamicPngStack::PngEncodeAsync failed.");
enc_req->callback = Persistent<Function>::New(callback);
enc_req->png_obj = png;
enc_req->png = NULL;
enc_req->png_len = 0;
enc_req->error = NULL;
eio_custom(EIO_PngEncode, EIO_PRI_DEFAULT, EIO_PngEncodeAfter, enc_req);
ev_ref(EV_DEFAULT_UC);
png->Ref();
return Undefined();
}
Handle<Value>
DynamicPngStack::PngEncodeAsync(const Arguments &args)
{
HandleScope scope;
if (args.Length() != 1)
return VException("One argument required - callback function.");
if (!args[0]->IsFunction())
return VException("First argument must be a function.");
Local<Function> callback = Local<Function>::Cast(args[0]);
DynamicPngStack *png = ObjectWrap::Unwrap<DynamicPngStack>(args.This());
encode_request *enc_req = (encode_request *)malloc(sizeof(*enc_req));
if (!enc_req)
return VException("malloc in DynamicPngStack::PngEncodeAsync failed.");
enc_req->callback = Persistent<Function>::New(callback);
enc_req->png_obj = png;
enc_req->png = NULL;
enc_req->png_len = 0;
enc_req->error = NULL;
uv_work_t* req = new uv_work_t;
req->data = enc_req;
uv_queue_work(uv_default_loop(), req, UV_PngEncode, (uv_after_work_cb)UV_PngEncodeAfter);
png->Ref();
return Undefined();
}
int
DynamicPngStack::EIO_PngEncode(eio_req *req)
{
encode_request *enc_req = (encode_request *)req->data;
DynamicPngStack *png = (DynamicPngStack *)enc_req->png_obj;
std::pair<Point, Point> optimal = png->optimal_dimension();
Point top = optimal.first, bot = optimal.second;
// printf("width, height: %d, %d\n", bot.x - top.x, bot.y - top.y);
png->offset = top;
png->width = bot.x - top.x;
png->height = bot.y - top.y;
unsigned char *data = (unsigned char*)malloc(sizeof(*data) * png->width * png->height * 4);
if (!data) {
enc_req->error = strdup("malloc failed in DynamicPngStack::EIO_PngEncode.");
return 0;
}
memset(data, 0xFF, png->width*png->height*4);
png->construct_png_data(data, top);
buffer_type pbt = (png->buf_type == BUF_BGR || png->buf_type == BUF_BGRA) ?
BUF_BGRA : BUF_RGBA;
try {
PngEncoder encoder(data, png->width, png->height, pbt);
encoder.encode();
free(data);
enc_req->png_len = encoder.get_png_len();
enc_req->png = (char *)malloc(sizeof(*enc_req->png)*enc_req->png_len);
if (!enc_req->png) {
enc_req->error = strdup("malloc in DynamicPngStack::EIO_PngEncode failed.");
return 0;
}
else {
memcpy(enc_req->png, encoder.get_png(), enc_req->png_len);
}
}
catch (const char *err) {
enc_req->error = strdup(err);
}
return 0;
}
int
DynamicPngStack::EIO_PngEncodeAfter(eio_req *req)
{
HandleScope scope;
ev_unref(EV_DEFAULT_UC);
encode_request *enc_req = (encode_request *)req->data;
DynamicPngStack *png = (DynamicPngStack *)enc_req->png_obj;
Handle<Value> argv[3];
if (enc_req->error) {
argv[0] = Undefined();
argv[1] = Undefined();
argv[2] = ErrorException(enc_req->error);
}
else {
Buffer *buf = Buffer::New(enc_req->png_len);
memcpy(BufferData(buf), enc_req->png, enc_req->png_len);
argv[0] = buf->handle_;
argv[1] = png->Dimensions();
argv[2] = Undefined();
}
TryCatch try_catch; // don't quite see the necessity of this
enc_req->callback->Call(Context::GetCurrent()->Global(), 3, argv);
if (try_catch.HasCaught())
FatalException(try_catch);
enc_req->callback.Dispose();
free(enc_req->png);
free(enc_req->error);
png->Unref();
free(enc_req);
return 0;
}
