#include "light.h"

Light::Light()
{
}

void Light::SetAmbientColor(float r, float g, float b, float a)
{
	float ambientColor[] = { r,g,b,a };
	glLightfv(mLightIdentifier, GL_AMBIENT, ambientColor);
}

void Light::SetDiffuseColor(float r, float g, float b, float a)
{
	float diffuseColor[] = { r,g,b,a };
	glLightfv(mLightIdentifier, GL_DIFFUSE, diffuseColor);
}

void Light::SetSpecularColor(float r, float g, float b, float a)
{
	float specularColor[] = { r,g,b,a };
	glLightfv(mLightIdentifier, GL_SPECULAR, specularColor);
}

void Light::Enable()
{
	glEnable(GL_LIGHTING);
	glEnable(mLightIdentifier);
}

DirectionLight::DirectionLight(GLenum light)
{
	mLightIdentifier = light;
}

void DirectionLight::SetPosition(float x, float y, float z)
{
	float pos[] = { x,y,z, 0.0f }; //这里齐次坐标写了0.0f代表这个光在最远处
	glLightfv(mLightIdentifier, GL_POSITION, pos);
}

PointLight::PointLight(GLenum light)
{
	mLightIdentifier = light;
	memset(mPosition, 0, sizeof(mPosition));
}

void PointLight::SetPosition(float x, float y, float z)
{
	//float pos[] = {x,y,z, 1.0f};//这里的齐次坐标为1.0代表在近处
	//glLightfv(mLightIdentifier, GL_POSITION, pos);
	mPosition[0] = x;
	mPosition[1] = y;
	mPosition[2] = z;
}

void PointLight::SetConstAttenuation(float v)
{
	glLightf(mLightIdentifier, GL_CONSTANT_ATTENUATION, v);
}

void PointLight::SetLinearAttenuation(float v)
{
	glLightf(mLightIdentifier, GL_LINEAR_ATTENUATION, v);
}

void PointLight::SetQuadricAttenuation(float v)
{
	glLightf(mLightIdentifier, GL_QUADRATIC_ATTENUATION, v);
}

void PointLight::Update(float x, float y, float z)
{
	float pos[] = {mPosition[0] - x, mPosition[1] - y, mPosition[2] - z, 1.0f};
	glLightfv(mLightIdentifier, GL_POSITION, pos);
}

SpotLight::SpotLight(GLenum light):PointLight(light)
{
}

void SpotLight::SetDirection(float x, float y, float z)
{
	float dir[] = { x,y,z };
	glLightfv(mLightIdentifier, GL_SPOT_DIRECTION, dir);//设置聚光灯的朝向
}

void SpotLight::SetExpone(float v)
{
	glLightf(mLightIdentifier, GL_SPOT_EXPONENT, v);//设置聚光度，其实这里是一个角度，在这个角度内光是不衰减的
}

void SpotLight::SetCutoff(float v)
{
	glLightf(mLightIdentifier, GL_SPOT_CUTOFF, v);//设置聚光范围
}