private static mat4 GetProjectionMatrix(this TSpotLight light)
{
const double angle = 90.0 / 180.0 * Math.PI; // in radians
const float aspectRatio = 1.0f;
// TODO: how to get a precise projection?
mat4 projection = glm.perspective((float)angle, aspectRatio, 0.1f, 50);
return(projection);
}
/// <summary>
/// Cast shadow.(Prepare shadow mapping texture)
/// </summary>
/// <param name="param"></param>
public override void Act(ActionParams param)
{
Scene scene = this.scene;
// Render ambient color.
{
var arg = new ShadowMappingAmbientEventArgs(param, scene.Camera, scene.AmbientColor);
RenderAmbientColor(scene.RootNode, arg);
}
foreach (var light in scene.Lights)
{
if (light is SpotLight || light is DirectionalLight)
{
LightTheScene(light, scene, param);
}
else if (light is PointLight)
{
var xLight = new TSpotLight(light.Position, TSpotLightDirection.X, light.Attenuation)
{
Diffuse = light.Diffuse, Specular = light.Specular,
};
var nxLight = new TSpotLight(light.Position, TSpotLightDirection.NX, light.Attenuation)
{
Diffuse = light.Diffuse, Specular = light.Specular,
};
var yLight = new TSpotLight(light.Position, TSpotLightDirection.Y, light.Attenuation)
{
Diffuse = light.Diffuse, Specular = light.Specular,
};
var nyLight = new TSpotLight(light.Position, TSpotLightDirection.NY, light.Attenuation)
{
Diffuse = light.Diffuse, Specular = light.Specular,
};
var zLight = new TSpotLight(light.Position, TSpotLightDirection.Z, light.Attenuation)
{
Diffuse = light.Diffuse, Specular = light.Specular,
};
var nzLight = new TSpotLight(light.Position, TSpotLightDirection.NZ, light.Attenuation)
{
Diffuse = light.Diffuse, Specular = light.Specular,
};
var lights = new TSpotLight[] { xLight, nxLight, yLight, nyLight, zLight, nzLight };
foreach (var item in lights)
{
LightTheScene(item, scene, param);
}
}
else
{
throw new Exception(string.Format("Unexpected light type:{0}", light.GetType().FullName));
}
}
}
private static void SetUniforms(this TSpotLight light, ShaderProgram program)
{
program.SetUniform("light.position", light.Position);
program.SetUniform("light.diffuse", light.Diffuse);
program.SetUniform("light.specular", light.Specular);
program.SetUniform("light.constant", light.Attenuation.Constant);
program.SetUniform("light.linear", light.Attenuation.Linear);
program.SetUniform("light.quadratic", light.Attenuation.Exp);
program.SetUniform("light.direction", light.Direction.ToVec3());
//program.SetUniform("light.cutOff", light.CutOff);
int lightUpRoutine = (int)light.Direction;
program.SetUniform("lightUpRoutine", lightUpRoutine);
}
private static mat4 GetViewMatrix(this TSpotLight light)
{
vec3 direction, up;
switch (light.Direction)
{
case TSpotLightDirection.X:
direction = new vec3(-1, 0, 0);
up = new vec3(0, 1, 0);
break;
case TSpotLightDirection.NX:
direction = new vec3(1, 0, 0);
up = new vec3(0, 1, 0);
break;
case TSpotLightDirection.Y:
direction = new vec3(0, -1, 0);
up = new vec3(0, 0, 1);
break;
case TSpotLightDirection.NY:
direction = new vec3(0, 1, 0);
up = new vec3(0, 0, 1);
break;
case TSpotLightDirection.Z:
direction = new vec3(0, 0, -1);
up = new vec3(0, 1, 0);
break;
case TSpotLightDirection.NZ:
direction = new vec3(0, 0, 1);
up = new vec3(0, 1, 0);
break;
default:
throw new NotDealWithNewEnumItemException(typeof(TSpotLightDirection));
}
mat4 view = glm.lookAt(light.Position, light.Position - direction, up);
return(view);
}