paysages3d/lib_paysages/lighting.c

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C
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#include <stdlib.h>
#include <math.h>
#include "shared/types.h"
#include "shared/functions.h"
#include "shared/constants.h"
#include "shared/globals.h"
static Color sun_color;
double sun_color_lum;
Vector3 sun_direction;
Vector3 sun_direction_inv;
void lightingSave(FILE* f)
{
}
void lightingLoad(FILE* f)
{
}
void lightingSetSunDirection(double x, double y, double z)
{
sun_direction.x = x;
sun_direction.y = y;
sun_direction.z = z;
sun_direction = v3Normalize(sun_direction);
sun_direction_inv = v3Scale(sun_direction, -1.0);
}
void lightingSetSunAngle(double hor, double ver)
{
lightingSetSunDirection(cos(hor) * cos(ver), sin(ver), -sin(hor) * cos(ver));
}
void lightingSetSunColor(Color col)
{
sun_color = col;
sun_color_lum = colorGetValue(&col);
}
Color lightingApply(Vector3 location, Vector3 normal, double shadowing, Color base, double reflection, double shininess)
{
Color result, light;
double ambient, diffuse, specular;
Vector3 view, reflect;
light.r = sun_color.r * (1.0 - 0.4 * shadowing);
light.g = sun_color.g * (1.0 - 0.4 * shadowing);
light.b = sun_color.b * (1.0 - 0.4 * shadowing);
normal = v3Normalize(normal);
view = v3Normalize(v3Sub(location, camera_location));
reflect = v3Sub(v3Scale(normal, 2.0 * v3Dot(sun_direction_inv, normal)), sun_direction_inv);
ambient = 0.2;
diffuse = v3Dot(sun_direction_inv, normal);
diffuse = pow(diffuse * 0.5 + 0.5, 2.0) * (1.0 - shadowing) + (diffuse * 0.5 + 0.3) * shadowing;
if (diffuse > 0.0)
{
if (shininess > 0.0)
{
specular = pow(v3Dot(reflect, view) * reflection, shininess * 10.0 + 1.0);
}
else
{
specular = 0.0;
}
}
else
{
diffuse = 0.0;
specular = 0.0;
}
result.r = base.r * ambient + base.r * diffuse * light.r + base.r * specular * light.r;
result.g = base.g * ambient + base.g * diffuse * light.g + base.g * specular * light.g;
result.b = base.b * ambient + base.b * diffuse * light.b + base.b * specular * light.b;
result.a = base.a;
return result;
}