#include "dvr_triangle.h"

int32_t Triangle::nextID()
{
	static int32_t id = 0;
	return id++;
}

davinci::fVector3 Triangle::randomColor()
{
	return davinci::fVector3(rand() * 0.8f / RAND_MAX, rand() * 0.8f / RAND_MAX, rand() * 0.8f / RAND_MAX);
}

void Triangle::build(int32_t canvasWidth, int32_t canvasHeight, davinci::AntiAliasingTech aaTech)
{
	m_pixels.clear();

	bool ccw = false;
	if ((m_p2 - m_p1).crossProduct(m_p0 - m_p2).z > 0) {
		ccw = true;
	}

	//build pixel data
	davinci::Rasterizer::drawTriangleLarrabee(aaTech,
		canvasWidth, canvasHeight,
		m_p0.xy(), m_p1.xy(), m_p2.xy(),
		[this](std::pair<int32_t, int32_t> pos, const davinci::fVector3& t, uint32_t mask) 
		{
			Pixel pixel;
			pixel.x = pos.first;
			pixel.y = pos.second;
			pixel.mask = mask;
			m_pixels.push_back(pixel);
		},
		ccw
	);
}