src/polygoncache.cpp

#include "polygoncache.h"
#include "documentmanager.h"

static void getObjectPolygons(
	Model* model,
	const int index,
	std::vector<gl::Polygon>& polygons_out,
	ldraw::GetPolygonsContext* context);

/**
 * @brief Gets a list of GL polygons that are used to represent this model.
 * @details Will build polygons if polygons are outdated.
 * @param documents Documents to use to resolve subfile references
 * @return vector of GL polygons
 */
const std::vector<gl::Polygon> &getCachedPolygons(
	PolygonCache *cache,
	Model *model,
	DocumentManager *documents)
{
	if (cache->needRecache)
	{
		cache->cachedPolygons.clear();
		const std::optional<ModelId> modelId = documents->findIdForModel(model);
		if (modelId.has_value())
		{
			ldraw::GetPolygonsContext context{modelId.value(), documents};
			for (int i = 0; i < model->size(); i += 1)
			{
				getObjectPolygons(model, i, cache->cachedPolygons, &context);
			}
		}
		cache->needRecache = false;
	}
	return cache->cachedPolygons;
}

/**
 * @brief Gets the GL polygons of the object at the specified position in the model
 * @param index Index of object in the model
 * @param polygons_out Vector to add polygons into
 * @param context Context to use to resolve subfile references
 */
static void getObjectPolygons(
	Model* model,
	const int index,
	std::vector<gl::Polygon>& polygons_out,
	ldraw::GetPolygonsContext* context)
{
	const ldraw::Object* object = (*model)[unsigned_cast(index)];
	object->getPolygons(polygons_out, context);
}