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student.c
461 lines (380 loc) · 15.9 KB
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student.c
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/******************************************************************************
* Projekt - Zaklady pocitacove grafiky - IZG
* spanel@fit.vutbr.cz
*
* $Id:$
*/
#include "student.h"
#include "transform.h"
#include "fragment.h"
#include <memory.h>
#include <math.h>
float myStudFrame = 0.0;
const S_Material MAT_WHITE_AMBIENT = { 1.0, 1.0, 1.0, 1.0 };
const S_Material MAT_WHITE_DIFFUSE = { 1.0, 1.0, 1.0, 1.0 };
const S_Material MAT_WHITE_SPECULAR = { 1.0, 1.0, 1.0, 1.0 };
/*****************************************************************************
* Globalni promenne a konstanty
*/
/* Typ/ID rendereru (nemenit) */
const int STUDENT_RENDERER = 1;
/*****************************************************************************
* Funkce vytvori vas renderer a nainicializuje jej
*/
S_Renderer * studrenCreate()
{
S_StudentRenderer * renderer = (S_StudentRenderer *)malloc(sizeof(S_StudentRenderer));
IZG_CHECK(renderer, "Cannot allocate enough memory");
/* inicializace default rendereru */
renderer->base.type = STUDENT_RENDERER;
renInit(&renderer->base);
/* nastaveni ukazatelu na upravene funkce */
/* napr. renderer->base.releaseFunc = studrenRelease; */
renderer->base.releaseFunc = studrenRelease;
renderer->base.projectTriangleFunc = studrenProjectTriangle;
/* inicializace nove pridanych casti */
int width, height;
S_RGBA *texture = loadBitmap(TEXTURE_FILENAME, &width, &height);
renderer->height = height;
renderer->width = width;
renderer->texture = texture;
return (S_Renderer *)renderer;
}
/*****************************************************************************
* Funkce korektne zrusi renderer a uvolni pamet
*/
void studrenRelease(S_Renderer **ppRenderer)
{
S_StudentRenderer * renderer;
if( ppRenderer && *ppRenderer )
{
/* ukazatel na studentsky renderer */
renderer = (S_StudentRenderer *)(*ppRenderer);
/* pripadne uvolneni pameti */
free(renderer->texture);
/* fce default rendereru */
renRelease(ppRenderer);
}
}
/******************************************************************************
* Nova fce pro rasterizaci trojuhelniku s podporou texturovani
* Upravte tak, aby se trojuhelnik kreslil s texturami
* (doplnte i potrebne parametry funkce - texturovaci souradnice, ...)
* v1, v2, v3 - ukazatele na vrcholy trojuhelniku ve 3D pred projekci
* n1, n2, n3 - ukazatele na normaly ve vrcholech ve 3D pred projekci
* t0, t1, t2 - souradnice textury
* x1, y1, ... - vrcholy trojuhelniku po projekci do roviny obrazovky
*/
void studrenDrawTriangle(S_Renderer *pRenderer,
S_Coords *v1, S_Coords *v2, S_Coords *v3,
S_Coords *n1, S_Coords *n2, S_Coords *n3,
S_Coords *t0, S_Coords *t1, S_Coords *t2,
int x1, int y1,
int x2, int y2,
int x3, int y3,
double h1, double h2, double h3
)
{
int minx, miny, maxx, maxy;
int a1, a2, a3, b1, b2, b3, c1, c2, c3;
int s1, s2, s3;
int x, y, e1, e2, e3;
double alpha, beta, gamma, w1, w2, w3, z, u, v;
S_RGBA col1, col2, col3, color;
IZG_ASSERT(pRenderer && v1 && v2 && v3 && n1 && n2 && n3);
/* vypocet barev ve vrcholech */
col1 = pRenderer->calcReflectanceFunc(pRenderer, v1, n1);
col2 = pRenderer->calcReflectanceFunc(pRenderer, v2, n2);
col3 = pRenderer->calcReflectanceFunc(pRenderer, v3, n3);
/* obalka trojuhleniku */
minx = MIN(x1, MIN(x2, x3));
maxx = MAX(x1, MAX(x2, x3));
miny = MIN(y1, MIN(y2, y3));
maxy = MAX(y1, MAX(y2, y3));
/* oriznuti podle rozmeru okna */
miny = MAX(miny, 0);
maxy = MIN(maxy, pRenderer->frame_h - 1);
minx = MAX(minx, 0);
maxx = MIN(maxx, pRenderer->frame_w - 1);
/* Pineduv alg. rasterizace troj.
hranova fce je obecna rovnice primky Ax + By + C = 0
primku prochazejici body (x1, y1) a (x2, y2) urcime jako
(y1 - y2)x + (x2 - x1)y + x1y2 - x2y1 = 0 */
/* normala primek - vektor kolmy k vektoru mezi dvema vrcholy, tedy (-dy, dx) */
a1 = y1 - y2;
a2 = y2 - y3;
a3 = y3 - y1;
b1 = x2 - x1;
b2 = x3 - x2;
b3 = x1 - x3;
/* koeficient C */
c1 = x1 * y2 - x2 * y1;
c2 = x2 * y3 - x3 * y2;
c3 = x3 * y1 - x1 * y3;
/* vypocet hranove fce (vzdalenost od primky) pro protejsi body */
s1 = a1 * x3 + b1 * y3 + c1;
s2 = a2 * x1 + b2 * y1 + c2;
s3 = a3 * x2 + b3 * y2 + c3;
if ( !s1 || !s2 || !s3 )
{
return;
}
/* normalizace, aby vzdalenost od primky byla kladna uvnitr trojuhelniku */
if( s1 < 0 )
{
a1 *= -1;
b1 *= -1;
c1 *= -1;
}
if( s2 < 0 )
{
a2 *= -1;
b2 *= -1;
c2 *= -1;
}
if( s3 < 0 )
{
a3 *= -1;
b3 *= -1;
c3 *= -1;
}
/* koeficienty pro barycentricke souradnice */
alpha = 1.0 / ABS(s2);
beta = 1.0 / ABS(s3);
gamma = 1.0 / ABS(s1);
S_RGBA newColor;
/* vyplnovani... */
for( y = miny; y <= maxy; ++y )
{
/* inicilizace hranove fce v bode (minx, y) */
e1 = a1 * minx + b1 * y + c1;
e2 = a2 * minx + b2 * y + c2;
e3 = a3 * minx + b3 * y + c3;
for( x = minx; x <= maxx; ++x )
{
if( e1 >= 0 && e2 >= 0 && e3 >= 0 )
{
/* interpolace pomoci barycentrickych souradnic
e1, e2, e3 je aktualni vzdalenost bodu (x, y) od primek */
w1 = alpha * e2;
w2 = beta * e3;
w3 = gamma * e1;
/* interpolace z-souradnice */
z = w1 * v1->z + w2 * v2->z + w3 * v3->z;
double jmenovatel = w1 / h1 + w2 / h2 + w3 / h3;
u = (w1 * t0->x / h1) + (w2 * t1->x / h2) + (w3 * t2->x / h3);
v = (w1 * t0->y / h1) + (w2 * t1->y / h2) + (w3 * t2->y / h3);
u = u / jmenovatel;
v = v / jmenovatel;
newColor = studrenTextureValue((S_StudentRenderer *)pRenderer, u, v);
/* interpolace barvy */
color.red = ROUND2BYTE(w1 * col1.red + w2 * col2.red + w3 * col3.red) * (newColor.red / 255.0);
color.green = ROUND2BYTE(w1 * col1.green + w2 * col2.green + w3 * col3.green) * (newColor.green / 255.0);
color.blue = ROUND2BYTE(w1 * col1.blue + w2 * col2.blue + w3 * col3.blue) * (newColor.blue / 255.0);
color.alpha = 255;
/* vykresleni bodu */
if( z < DEPTH(pRenderer, x, y) )
{
PIXEL(pRenderer, x, y) = color;
DEPTH(pRenderer, x, y) = z;
}
}
/* hranova fce o pixel vedle */
e1 += a1;
e2 += a2;
e3 += a3;
}
}
}
/******************************************************************************
* Vykresli i-ty trojuhelnik n-teho klicoveho snimku modelu
* pomoci nove fce studrenDrawTriangle()
* Pred vykreslenim aplikuje na vrcholy a normaly trojuhelniku
* aktualne nastavene transformacni matice!
* Upravte tak, aby se model vykreslil interpolovane dle parametru n
* (cela cast n udava klicovy snimek, desetinna cast n parametr interpolace
* mezi snimkem n a n + 1)
* i - index trojuhelniku
* n - index klicoveho snimku (float pro pozdejsi interpolaci mezi snimky)
*/
void studrenProjectTriangle(S_Renderer *pRenderer, S_Model *pModel, int i, float n)
{
S_Coords aa, bb, cc; /* souradnice vrcholu po transformaci */
S_Coords naa, nbb, ncc; /* normaly ve vrcholech po transformaci */
S_Coords nn; /* normala trojuhelniku po transformaci */
int u1, v1, u2, v2, u3, v3; /* souradnice vrcholu po projekci do roviny obrazovky */
S_Triangle * triangle;
int vertexOffset, normalOffset; /* offset pro vrcholy a normalove vektory trojuhelniku */
int i0, i1, i2, in; /* indexy vrcholu a normaly pro i-ty trojuhelnik n-teho snimku */
S_Coords aa1, bb1, cc1; /* souradnice vrcholu po transformaci */
S_Coords naa1, nbb1, ncc1; /* normaly ve vrcholech po transformaci */
S_Coords nn1; /* normala trojuhelniku po transformaci */
int vertexOffset1, normalOffset1;
int i01, i11, i21, in1; /* indexy vrcholu a normaly pro i-ty trojuhelnik (n+1)-teho snimku */
IZG_ASSERT(pRenderer && pModel && i >= 0 && i < trivecSize(pModel->triangles) && n >= 0 );
int N = (int) floor(n);
float xN = n - floor(n);
/* z modelu si vytahneme i-ty trojuhelnik */
triangle = trivecGetPtr(pModel->triangles, i);
/* ziskame offset pro vrcholy n-teho snimku */
vertexOffset = (N % pModel->frames) * pModel->verticesPerFrame;
vertexOffset1 = ((N + 1) % pModel->frames) * pModel->verticesPerFrame;
/* ziskame offset pro normaly trojuhelniku n-teho snimku */
normalOffset = (N % pModel->frames) * pModel->triangles->size;
normalOffset1 = ((N + 1) % pModel->frames) * pModel->triangles->size;
/* indexy vrcholu pro i-ty trojuhelnik n-teho snimku - pricteni offsetu */
i0 = triangle->v[ 0 ] + vertexOffset;
i1 = triangle->v[ 1 ] + vertexOffset;
i2 = triangle->v[ 2 ] + vertexOffset;
i01 = triangle->v[ 0 ] + vertexOffset1;
i11 = triangle->v[ 1 ] + vertexOffset1;
i21 = triangle->v[ 2 ] + vertexOffset1;
/* index normaloveho vektoru pro i-ty trojuhelnik n-teho snimku - pricteni offsetu */
in = triangle->n + normalOffset;
in1 = triangle->n + normalOffset1;
/* transformace vrcholu matici model */
trTransformVertex(&aa, cvecGetPtr(pModel->vertices, i0));
trTransformVertex(&bb, cvecGetPtr(pModel->vertices, i1));
trTransformVertex(&cc, cvecGetPtr(pModel->vertices, i2));
trTransformVertex(&aa1, cvecGetPtr(pModel->vertices, i01));
trTransformVertex(&bb1, cvecGetPtr(pModel->vertices, i11));
trTransformVertex(&cc1, cvecGetPtr(pModel->vertices, i21));
/* Interpolace vrcholu*/
aa.x = (1 - xN) * aa.x + xN * aa1.x;
aa.y = (1 - xN) * aa.y + xN * aa1.y;
aa.z = (1 - xN) * aa.z + xN * aa1.z;
bb.x = (1 - xN) * bb.x + xN * bb1.x;
bb.y = (1 - xN) * bb.y + xN * bb1.y;
bb.z = (1 - xN) * bb.z + xN * bb1.z;
cc.x = (1 - xN) * cc.x + xN * cc1.x;
cc.y = (1 - xN) * cc.y + xN * cc1.y;
cc.z = (1 - xN) * cc.z + xN * cc1.z;
/* promitneme vrcholy trojuhelniku na obrazovku */
double h0 = trProjectVertex(&u1, &v1, &aa);
double h1 = trProjectVertex(&u2, &v2, &bb);
double h2 = trProjectVertex(&u3, &v3, &cc);
/* pro osvetlovaci model transformujeme take normaly ve vrcholech */
trTransformVector(&naa, cvecGetPtr(pModel->normals, i0));
trTransformVector(&nbb, cvecGetPtr(pModel->normals, i1));
trTransformVector(&ncc, cvecGetPtr(pModel->normals, i2));
trTransformVector(&naa1, cvecGetPtr(pModel->normals, i01));
trTransformVector(&nbb1, cvecGetPtr(pModel->normals, i11));
trTransformVector(&ncc1, cvecGetPtr(pModel->normals, i21));
/* Interpolace normal */
naa.x = (1 - xN) * naa.x + xN * naa1.x;
naa.y = (1 - xN) * naa.y + xN * naa1.y;
naa.z = (1 - xN) * naa.z + xN * naa1.z;
nbb.x = (1 - xN) * nbb.x + xN * nbb1.x;
nbb.y = (1 - xN) * nbb.y + xN * nbb1.y;
nbb.z = (1 - xN) * nbb.z + xN * nbb1.z;
ncc.x = (1 - xN) * ncc.x + xN * ncc1.x;
ncc.y = (1 - xN) * ncc.y + xN * ncc1.y;
ncc.z = (1 - xN) * ncc.z + xN * ncc1.z;
/* normalizace normal */
coordsNormalize(&naa);
coordsNormalize(&nbb);
coordsNormalize(&ncc);
/* transformace normaly trojuhelniku matici model */
trTransformVector(&nn, cvecGetPtr(pModel->trinormals, in));
trTransformVector(&nn1, cvecGetPtr(pModel->trinormals, in1));
/* Interpolace normaly */
nn.x = (1 - xN) * nn.x + xN * nn1.x;
nn.y = (1 - xN) * nn.y + xN * nn1.y;
nn.z = (1 - xN) * nn.z + xN * nn1.z;
/* normalizace normaly */
coordsNormalize(&nn);
/* je troj. privraceny ke kamere, tudiz viditelny? */
if( !renCalcVisibility(pRenderer, &aa, &nn) )
{
/* odvracene troj. vubec nekreslime */
return;
}
S_Triangle *texture = trivecGetPtr(pModel->triangles, i);
/* rasterizace trojuhelniku */
studrenDrawTriangle(pRenderer,
&aa, &bb, &cc,
&naa, &nbb, &ncc,
&triangle->t[0], &triangle->t[1], &triangle->t[2],
u1, v1, u2, v2, u3, v3,
h0, h1, h2
);
}
/******************************************************************************
* Vraci hodnotu v aktualne nastavene texture na zadanych
* texturovacich souradnicich u, v
* Pro urceni hodnoty pouziva bilinearni interpolaci
* Pro otestovani vraci ve vychozim stavu barevnou sachovnici dle uv souradnic
* u, v - texturovaci souradnice v intervalu 0..1, ktery odpovida sirce/vysce textury
*/
S_RGBA studrenTextureValue( S_StudentRenderer * pRenderer, double u, double v )
{
u = u * pRenderer->width;
v = v * pRenderer->height;
int U = (int) floor(u);
int V = (int) floor(v);
double xU = u - floor(u);
double xV = u - floor(u);
S_RGBA color;
if (!isnan(u) && !isnan(v)){
color.red = pRenderer->texture[U * pRenderer->height + V].red * (1 - xU) * (1 - xV)
+ pRenderer->texture[U * pRenderer->height + (V + 1)].red * (1 - xU) * xV
+ pRenderer->texture[(U + 1) * pRenderer->height + V].red * xU * (1 - xV)
+ pRenderer->texture[(U + 1) * pRenderer->height + (V + 1)].red * xU * xV;
color.green = pRenderer->texture[U * pRenderer->height + V].green * (1 - xU) * (1 - xV)
+ pRenderer->texture[U * pRenderer->height + (V + 1)].green * (1 - xU) * xV
+ pRenderer->texture[(U + 1) * pRenderer->height + V].green * xU * (1 - xV)
+ pRenderer->texture[(U + 1) * pRenderer->height + (V + 1)].green * xU * xV;
color.blue = pRenderer->texture[U * pRenderer->height + V].blue * (1 - xU) * (1 - xV)
+ pRenderer->texture[U * pRenderer->height + (V + 1)].blue * (1 - xU) * xV
+ pRenderer->texture[(U + 1) * pRenderer->height + V].blue * xU * (1 - xV)
+ pRenderer->texture[(U + 1) * pRenderer->height + (V + 1)].blue * xU * xV;
} else {
color.red = 90;
color.blue = 60;
color.green = 90;
}
return (makeColor(color.red, color.green, color.blue));
}
/******************************************************************************
******************************************************************************
* Funkce pro vyrenderovani sceny, tj. vykresleni modelu
* Upravte tak, aby se model vykreslil animovane
* (volani renderModel s aktualizovanym parametrem n)
*/
void renderStudentScene(S_Renderer *pRenderer, S_Model *pModel)
{
/* test existence frame bufferu a modelu */
IZG_ASSERT(pModel && pRenderer);
/* nastavit projekcni matici */
trProjectionPerspective(pRenderer->camera_dist, pRenderer->frame_w, pRenderer->frame_h);
/* vycistit model matici */
trLoadIdentity();
/* nejprve nastavime posuv cele sceny od/ke kamere */
trTranslate(0.0, 0.0, pRenderer->scene_move_z);
/* nejprve nastavime posuv cele sceny v rovine XY */
trTranslate(pRenderer->scene_move_x, pRenderer->scene_move_y, 0.0);
/* natoceni cele sceny - jen ve dvou smerech - mys je jen 2D... :( */
trRotateX(pRenderer->scene_rot_x);
trRotateY(pRenderer->scene_rot_y);
/* nastavime material */
/*
renMatAmbient(pRenderer, &MAT_RED_AMBIENT);
renMatDiffuse(pRenderer, &MAT_RED_DIFFUSE);
renMatSpecular(pRenderer, &MAT_RED_SPECULAR);
//*/
renMatAmbient(pRenderer, &MAT_WHITE_AMBIENT);
renMatDiffuse(pRenderer, &MAT_WHITE_DIFFUSE);
renMatSpecular(pRenderer, &MAT_WHITE_SPECULAR);
/* a vykreslime nas model (ve vychozim stavu kreslime pouze snimek 0) */
renderModel(pRenderer, pModel, myStudFrame);
}
/* Callback funkce volana pri tiknuti casovace
* ticks - pocet milisekund od inicializace */
void onTimer( int ticks )
{
/* uprava parametru pouzivaneho pro vyber klicoveho snimku
* a pro interpolaci mezi snimky */
myStudFrame = (float)ticks / 99.0;
}
/*****************************************************************************
*****************************************************************************/