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| -rw-r--r-- | README.md | 7 | ||||
| -rw-r--r-- | cube3D.c | 240 |
2 files changed, 247 insertions, 0 deletions
diff --git a/README.md b/README.md new file mode 100644 index 0000000..61b9d92 --- /dev/null +++ b/README.md @@ -0,0 +1,7 @@ +# Cube3D +É um programa simples que utiliza da biblioteca SDL para desenhar um cubo e rotacioná-lo. + +Para compilar: +''' +gcc cube3D.c $(pkgconf --cflags --libs sdl2) -lm +'''
\ No newline at end of file diff --git a/cube3D.c b/cube3D.c new file mode 100644 index 0000000..8e6d1cb --- /dev/null +++ b/cube3D.c @@ -0,0 +1,240 @@ +#include <SDL2/SDL.h> +#include <SDL2/SDL_error.h> +#include <SDL2/SDL_pixels.h> +#include <SDL2/SDL_stdinc.h> +#include <SDL2/SDL_video.h> +#include <math.h> +#include <stdbool.h> +#define MAX(a, b)(a>b?a:b) +#define MIN(a, b)(a<b?a:b) + +#define WIDTH 640 +#define HEIGHT 640 + +SDL_Window *win; +SDL_Surface *winSurf; + +typedef struct{ + double x, y; +}point; + +typedef struct{ + int x, y; +}pointDraw; + +typedef struct{ + double x, y, z; +}point3D; + +int init(); +void kill(); +pointDraw map(point p); +point p3d2p(point3D p); +void DrawPixel(SDL_Surface* screen, pointDraw p, Uint32 color); +void DrawLine(pointDraw a, pointDraw b, Uint32 color); +void drawCube(); +void rotateCube(double a, double b, double c); +void DrawEixos(); + +bool loop(); + +point3D cubo3D[8]; + +int main(int argc, char* argv[]){ + init(); + cubo3D[0].x = -0.5 ; cubo3D[0].y = 0.5; cubo3D[0].z = -0.5; + cubo3D[1].x = 0.5; cubo3D[1].y = 0.5; cubo3D[1].z = -0.5; + cubo3D[2].x = 0.5; cubo3D[2].y = -0.5 ; cubo3D[2].z = -0.5; + cubo3D[3].x = -0.5 ; cubo3D[3].y = -0.5 ; cubo3D[3].z = -0.5; + cubo3D[4].x = -0.5 ; cubo3D[4].y = 0.5; cubo3D[4].z = 0.5; + cubo3D[5].x = 0.5; cubo3D[5].y = 0.5; cubo3D[5].z = 0.5; + cubo3D[6].x = 0.5; cubo3D[6].y = -0.5 ; cubo3D[6].z = 0.5; + cubo3D[7].x = -0.5; cubo3D[7].y = -0.5 ; cubo3D[7].z = 0.5; + + // point p1 = {-1, -1}; + // point p2 = {0, 0}; + // printf("%d %d\n%d %d\n", map(p1).x, map(p1).y, map(p2).x, map(p2).y); + //DrawLine(map(p1), map(p2)); + drawCube(); + while(loop()){ + SDL_Delay(10); + } + //winSurf->pixels = pixels; + //SDL_UpdateWindowSurface(win); + + // getchar(); + kill(); +} + +void DrawEixos(){ + pointDraw a = {320, 0}; + pointDraw b = {320, 640}; + DrawLine(a, b, 0xFFFFFF); + pointDraw c = {0, 320}; + pointDraw d = {640, 320}; + DrawLine(c, d, 0xFFFFFF); +} + +void rotateCube(double a, double b, double c){ + double Rx[3][3] = {{cos(a), -sin(a), 0},{sin(a), cos(a), 0},{0, 0, 1}}; + double Ry[3][3] = {{cos(b), 0, sin(b)}, {0, 1, 0}, {-sin(b), 0, cos(b)}}; + double Rz[3][3] = {{1, 0, 0}, {0, cos(c), -sin(c)}, {0, sin(c), cos(c)}}; + for(int i=0; i<8; ++i){ + point3D tmp = cubo3D[i]; + cubo3D[i].x = Rx[0][0]*tmp.x + Rx[0][1]*tmp.y + Rx[0][2]*tmp.z; + cubo3D[i].y = Rx[1][0]*tmp.x + Rx[1][1]*tmp.y + Rx[1][2]*tmp.z; + cubo3D[i].z = Rx[2][0]*tmp.x + Rx[2][1]*tmp.y + Rx[2][2]*tmp.z; + + tmp = cubo3D[i]; + cubo3D[i].x = Ry[0][0]*tmp.x + Ry[0][1]*tmp.y + Ry[0][2]*tmp.z; + cubo3D[i].y = Ry[1][0]*tmp.x + Ry[1][1]*tmp.y + Ry[1][2]*tmp.z; + cubo3D[i].z = Ry[2][0]*tmp.x + Ry[2][1]*tmp.y + Ry[2][2]*tmp.z; + + tmp = cubo3D[i]; + cubo3D[i].x = Rz[0][0]*tmp.x + Rz[0][1]*tmp.y + Rz[0][2]*tmp.z; + cubo3D[i].y = Rz[1][0]*tmp.x + Rz[1][1]*tmp.y + Rz[1][2]*tmp.z; + cubo3D[i].z = Rz[2][0]*tmp.x + Rz[2][1]*tmp.y + Rz[2][2]*tmp.z; + } +} + +void drawCube(){ + for(int i=0; i<4; ++i){ + if(i != 3){ + DrawLine(map(p3d2p(cubo3D[i])), map(p3d2p(cubo3D[i+1])), 0x00FF00); + DrawLine(map(p3d2p(cubo3D[i+4])), map(p3d2p(cubo3D[i+5])), 0x00FF00); + }else{ + DrawLine(map(p3d2p(cubo3D[i])), map(p3d2p(cubo3D[0])), 0x00FF00); + DrawLine(map(p3d2p(cubo3D[i+4])), map(p3d2p(cubo3D[4])), 0x00FF00); + } + DrawLine(map(p3d2p(cubo3D[i])), map(p3d2p(cubo3D[i+4])), 0x00FF00); + } +} + +point p3d2p(point3D p){ + point r; + r.x = p.x; + r.y = p.y; + return r; +} + +pointDraw map(point p){ + pointDraw r; + r.x = 320*(p.x+1); + r.y = -320*(p.y+1)+640; + return r; +} + +bool loop(){ + SDL_Event event; + + while(SDL_PollEvent(&event) != 0){ + switch(event.type){ + case SDL_QUIT: + return false; + } + } + SDL_FillRect(winSurf, NULL, 0x000000); + DrawEixos(); + drawCube(); + + rotateCube(0.005, 0.005, 0.005); + + + SDL_UpdateWindowSurface(win); + return true; +} + + + +void DrawLine(pointDraw a, pointDraw b, Uint32 color){ + int dx = abs(a.x - b.x); + int dy = abs(a.y - b.y); + + + if(dx >= dy && dx != 0){ + double m = 1.0*(a.y-b.y)/(a.x - b.x); + double q = a.y - m * a.x; + + int xmin = MIN(a.x, b.x); + int xmax = a.x + b.x - xmin; + + pointDraw p; + for(int i=xmin; i < xmax; ++i){ + p.x = i; + double tmp = m * p.x + q; + + if(tmp - (int)tmp <= 0.5) p.y = (int) tmp; + else p.y = (int) tmp + 1; + + DrawPixel(winSurf, p, color); + } + }else{ + //double m1 = 1.0*(a.x-b.x)/(a.y-b.y); + + if(a.x-b.x != 0){ + double m = 1.0*(a.y-b.y)/(a.x - b.x); + double q = a.y - m * a.x; + + int ymin = MIN(a.y, b.y); + int ymax = a.y + b.y - ymin; + + pointDraw p; + for(int i=ymin; i<ymax; ++i){ + p.y = i; + double tmp = (p.y-q)/m; + + if(tmp - (int)tmp <= 0.5) p.x = (int) tmp; + else p.x = (int) tmp + 1; + + DrawPixel(winSurf, p, color); + } + }else{ + int ymin = MIN(a.y, b.y); + int ymax = a.y + b.y - ymin; + + pointDraw p; + p.x = a.x; + for(int i=ymin; i<ymax; ++i){ + p.y = i; + DrawPixel(winSurf, p, color); + } + } + } +} + +void DrawPixel(SDL_Surface* screen, pointDraw p, Uint32 color){ + if(p.x > 640 || p.x < 0 || p.y > 640 || p.y < 0) return; + + Uint32 *pixels = (Uint32*)screen->pixels; + Uint32 *pixel = pixels + p.y * screen->pitch/4 + p.x; + //*pixel = SDL_MapRGB(screen->format, 0xFF, 0x00, 0x00); + *pixel = color; +} + +int init(){ + if(SDL_Init(SDL_INIT_EVERYTHING) < 0){ + printf("ERRO: Nao foi possivel iniciar o SDL:\n\t%s\n", SDL_GetError()); + return 0; + } + + win = SDL_CreateWindow("3DCube", + SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, + WIDTH, HEIGHT, SDL_WINDOW_SHOWN); + if(!win){ + printf("ERRO: Nao foi possibel criar uma janela:\n\t%s\n", SDL_GetError()); + return 0; + } + + winSurf = SDL_GetWindowSurface(win); + if(!winSurf){ + printf("ERRO: Nao foi possivel pegar a surface da janela:\n\t%s\n", SDL_GetError()); + return 0; + } + + return 1; +} + +void kill(){ + SDL_DestroyWindow(win); + SDL_Quit(); +} |