void renLightPosition(S_Renderer *pRenderer, const S_Coords *pPosition)
{
IZG_ASSERT(pRenderer && pPosition);
pRenderer->light_position = *pPosition;
}
void renMatSpecular(S_Renderer *pRenderer, const S_Material *pParams)
{
IZG_ASSERT(pRenderer && pParams);
pRenderer->mat_specular = *pParams;
}
void renMatDiffuse(S_Renderer *pRenderer, const S_Material *pParams)
{
IZG_ASSERT(pRenderer && pParams);
pRenderer->mat_diffuse = *pParams;
}
void renMatAmbient(S_Renderer *pRenderer, const S_Material *pParams)
{
IZG_ASSERT(pRenderer && pParams);
pRenderer->mat_ambient = *pParams;
}
void onKeyboard(SDL_KeyboardEvent *key)
{
int width, height;
/* test existence rendereru */
IZG_ASSERT(renderer);
/* vetveni podle stisknute klavesy */
switch( key->keysym.sym )
{
/* ukonceni programu - klavesa Esc nebo q */
case SDLK_ESCAPE:
case SDLK_q:
quit = 1;
break;
/* prepnuti do celoobrazovkoveho modu */
case SDLK_f:
SDL_WM_ToggleFullScreen(screen);
break;
/* prepnuti na studentsky renderer */
case SDLK_p:
/* zapamatovani aktualni velikosti frame bufferu */
width = renderer->frame_w;
height = renderer->frame_h;
/* zruseni a znovu vytvoreni rendereru */
renderer->releaseFunc(&renderer);
renderer = studrenCreate();
renderer->createBuffersFunc(renderer, width, height);
/* zmena titulku okna */
SDL_WM_SetCaption(PROGRAM_TITLE_STUDENT, 0);
break;
/* prepnuti na originalni renderer */
case SDLK_o:
width = renderer->frame_w;
height = renderer->frame_h;
renderer->releaseFunc(&renderer);
renderer = renCreate();
renderer->createBuffersFunc(renderer, width, height);
SDL_WM_SetCaption(PROGRAM_TITLE, 0);
break;
/* posun kamery pomoci klaves */
case SDLK_DOWN:
renSceneMoveXY(renderer, 0, 1);
break;
case SDLK_UP:
renSceneMoveXY(renderer, 0, -1);
break;
case SDLK_LEFT:
renSceneMoveXY(renderer, -1, 0);
break;
case SDLK_RIGHT:
renSceneMoveXY(renderer, 1, 0);
break;
default:
break;
}
}
S_RGBA studrenPhongReflectance(S_Renderer *pRenderer, const S_Coords *point, const S_Coords *normal)
{
S_Coords lvec, eyevec, reflect;
double diffuse, specular, reflect_scalar;
double r, g, b;
/* If = Ia + Id + Is */
S_RGBA color;
IZG_ASSERT(pRenderer && point && normal);
/* vektor ke zdroji svetla */
lvec = makeCoords(pRenderer->light_position.x - point->x,
pRenderer->light_position.y - point->y,
pRenderer->light_position.z - point->z);
coordsNormalize(&lvec);
/* vektor ke kamere */
eyevec = makeCoords(-point->x,
-point->y,
-pRenderer->camera_dist - point->z);
coordsNormalize(&eyevec);
/* ambientni cast -- Ia = (Al * Am) + (As * Am) */
/* As je barva sceny, muzeme zanedbat */
r = pRenderer->light_ambient.red * pRenderer->mat_ambient.red;
g = pRenderer->light_ambient.green * pRenderer->mat_ambient.green;
b = pRenderer->light_ambient.blue * pRenderer->mat_ambient.blue;
/* difuzni cast -- Id = Dl * Dm * LambertTerm */
/* LambertTerm = dot(N, L) */
diffuse = lvec.x * normal->x + lvec.y * normal->y + lvec.z * normal->z;
if( diffuse > 0 )
{
r += diffuse * pRenderer->light_diffuse.red * pRenderer->mat_diffuse.red;
g += diffuse * pRenderer->light_diffuse.green * pRenderer->mat_diffuse.green;
b += diffuse * pRenderer->light_diffuse.blue * pRenderer->mat_diffuse.blue;
}
/* odraziva cast -- Is = Sm * Sl * pow( max( dot(R, E), 0.0), f ) */
/* R = reflect(-L, N) = 2 * dot(N, L) * N - L */
reflect_scalar = 2 * (normal->x * lvec.x + normal->y * lvec.y + normal->z * lvec.z);
reflect.x = reflect_scalar * normal->x - lvec.x;
reflect.y = reflect_scalar * normal->y - lvec.y;
reflect.z = reflect_scalar * normal->z - lvec.z;
specular = pow(
MAX(reflect.x * eyevec.x + reflect.y * eyevec.y + reflect.z * eyevec.z, 0.0f),
((S_StudentRenderer*)pRenderer)->mat_shininess);
r += specular * pRenderer->light_specular.red * pRenderer->mat_specular.red;
g += specular * pRenderer->light_specular.green * pRenderer->mat_specular.green;
b += specular * pRenderer->light_specular.blue * pRenderer->mat_specular.blue;
/* saturace osvetleni*/
r = MIN(1, r);
g = MIN(1, g);
b = MIN(1, b);
/* kreslici barva */
color.red = ROUND2BYTE(255 * r);
color.green = ROUND2BYTE(255 * g);
color.blue = ROUND2BYTE(255 * b);
return color;
}
