-/* $Id$
-
-This file is part of libmspgl
-Copyright © 2007 Mikko Rasa, Mikkosoft Productions
-Distributed under the LGPL
-*/
-
#ifndef MSP_GL_LIGHT_H_
#define MSP_GL_LIGHT_H_
+#include <vector>
+#include <msp/datafile/objectloader.h>
#include "color.h"
+#include "placeable.h"
namespace Msp {
namespace GL {
-class Light
+class Matrix;
+class ProgramData;
+
+/**
+Stores properties of a single light source. Lights can be directional, point
+lights or spotlights. No explicit type parameter is provided; rather the
+other parameters determine what kind of light it is. If the fourth component
+of position is zero, it's a directional light. Otherwise, if the spot cutoff
+is not 180 degrees, it's a spotlight. Otherwise it's an omnidirectional point
+light.
+
+Lights are usually grouped with a Lighting object, which can be used in a
+Pipeline::Pass.
+
+Lights do not cast shadows by themselves. See ShadowMap for that.
+*/
+class Light: public Placeable
{
+public:
+ class Loader: public DataFile::ObjectLoader<Light>
+ {
+ public:
+ Loader(Light &);
+
+ private:
+ void attenuation(float, float, float);
+ void diffuse(float, float, float);
+ void position(float, float, float, float);
+ void specular(float, float, float);
+ void spot_direction(float, float, float);
+ void spot_exponent(float);
+ void spot_cutoff(float);
+ };
+
private:
- Color ambient;
Color diffuse;
Color specular;
- float x, y, z, w;
- float sdx, sdy, sdz;
+ Vector4 position;
+ Vector3 spot_dir;
+ Vector3 direction;
float spot_exp;
- float spot_cutoff;
+ Geometry::Angle<float> spot_cutoff;
float attenuation[3];
- static unsigned current;
-
public:
Light();
- void set_ambient(const Color &c);
+
+private:
+ void update_matrix();
+
+public:
+ /** Sets the diffuse (direction-independent) color of the Light. Provided
+ to shaders with the name light_sources[i].diffuse. */
void set_diffuse(const Color &c);
+
+ /** Sets the specular (direction-dependent) color of the Light. Provided to
+ shaders with the name light_sources[i].specular. */
void set_specular(const Color &c);
- void set_position(float, float, float, float);
- void apply() const;
- void apply_to(unsigned) const;
- static void activate(unsigned);
+ const Color &get_diffuse() const { return diffuse; }
+ const Color &get_specular() const { return specular; }
+
+ /** Sets the postion and orientation of the Light from a matrix. Negative Z
+ axis is used as the spot direction, other axes are ignored. */
+ virtual void set_matrix(const Matrix &);
+
+ /** Sets the position of the Light. For a directional light, set the xyz
+ components to a vector pointing towards the light and the w component to 0. */
+ void set_position(const Vector4 &);
+
+ const Vector4 &get_position() const { return position; }
+
+ /** Sets the direction of a spotlight. Has no effect if spotlight cutoff is
+ not set. */
+ void set_spot_direction(const Vector3 &);
+
+ /** Sets the angular falloff exponent of the spotlight. Must be >= 0. */
+ void set_spot_exponent(float);
+
+ /** Sets the cutoff angle of a spotlight. Beyond this angle from its axis
+ the spotlight provides no illumination. Must be between 0 and 90 degrees,
+ or exactly 180 degrees to indicate a non-spotlight. */
+ void set_spot_cutoff(const Geometry::Angle<float> &);
+
+ /** Disables spotlight, reverting to an omnidirectional point light.
+ Equivalent to setting the spot cutoff to 180 degrees. */
+ void disable_spot_cutoff();
+
+ const Vector3 &get_spot_direction() const { return spot_dir; }
+ float get_spot_exponent() const { return spot_exp; }
+ const Geometry::Angle<float> &get_spot_cutoff() const { return spot_cutoff; }
+ void set_attenuation(float, float, float);
+ const float *get_attenuation() const { return attenuation; }
+
+ /** Updates a ProgramData object with the uniforms for the Light. A view
+ matrix and light source index must be passed in. */
+ void update_shader_data(ProgramData &, const Matrix &, unsigned) const;
};
} // namespace GL