mrmBot-Matrix/natives/globe.cc
2022-05-23 09:47:59 -05:00

89 lines
No EOL
3.1 KiB
C++

#include <napi.h>
#include <vips/vips8>
using namespace std;
using namespace vips;
Napi::Value Globe(const Napi::CallbackInfo &info) {
Napi::Env env = info.Env();
try {
Napi::Object obj = info[0].As<Napi::Object>();
Napi::Buffer<char> data = obj.Get("data").As<Napi::Buffer<char>>();
string type = obj.Get("type").As<Napi::String>().Utf8Value();
string basePath = obj.Get("basePath").As<Napi::String>().Utf8Value();
VOption *options = VImage::option();
VImage in =
VImage::new_from_buffer(
data.Data(), data.Length(), "",
type == "gif" ? options->set("n", -1)->set("access", "sequential")
: options)
.colourspace(VIPS_INTERPRETATION_sRGB);
if (!in.has_alpha()) in = in.bandjoin(255);
int width = in.width();
int page_height = vips_image_get_page_height(in.get_image());
int n_pages = type == "gif" ? vips_image_get_n_pages(in.get_image()) : 30;
double size = min(width, page_height);
string diffPath = basePath + "assets/images/globediffuse.png";
VImage diffuse =
VImage::new_from_file(diffPath.c_str())
.resize(size / 500.0,
VImage::option()->set("kernel", VIPS_KERNEL_CUBIC)) /
255;
string specPath = basePath + "assets/images/globespec.png";
VImage specular =
VImage::new_from_file(specPath.c_str())
.resize(size / 500.0,
VImage::option()->set("kernel", VIPS_KERNEL_CUBIC));
string distortPath = basePath + "assets/images/spheremap.png";
VImage distort =
(VImage::new_from_file(distortPath.c_str())
.resize(size / 500.0,
VImage::option()->set("kernel", VIPS_KERNEL_CUBIC)) /
65535) *
size;
vector<VImage> img;
for (int i = 0; i < n_pages; i++) {
VImage img_frame =
type == "gif" ? in.crop(0, i * page_height, width, page_height) : in;
VImage resized = img_frame.resize(
size / (double)width,
VImage::option()->set("vscale", size / (double)page_height));
VImage rolled = img_frame.wrap(
VImage::option()->set("x", width * i / n_pages)->set("y", 0));
VImage extracted = rolled.extract_band(0, VImage::option()->set("n", 3));
VImage mapped = extracted.mapim(distort);
VImage composited = mapped * diffuse + specular;
VImage frame = composited.bandjoin(diffuse > 0.0);
img.push_back(frame);
}
VImage final = VImage::arrayjoin(img, VImage::option()->set("across", 1));
final.set(VIPS_META_PAGE_HEIGHT, size);
if (type != "gif") {
vector<int> delay(30, 50);
final.set("delay", delay);
}
void *buf;
size_t length;
final.write_to_buffer(".gif", &buf, &length);
Napi::Object result = Napi::Object::New(env);
result.Set("data", Napi::Buffer<char>::Copy(env, (char *)buf, length));
result.Set("type", "gif");
return result;
} catch (std::exception const &err) {
throw Napi::Error::New(env, err.what());
} catch (...) {
throw Napi::Error::New(env, "Unknown error");
}
}