Text in C++ - BlitzCoder.net

-=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- (c) WidthPadding Industries 1987 0\|513\|0 -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=-
Socoder -> C/C++/C#/Other -> Text in C++
Sun, 12 Aug 2007, 00:05
irondirgible	I recently started programming in C++ from a book and an online SDL tutorial. As many of you may know, basic SDL does not have font- or text-related functions. I spent several days looking for solutions, trying FreeType2 and SDL_ttf. Even with the proper header (ft2header.h), I couldn't get the functions to work (the defined structures were allowed, though). I am using Code::Blocks. I believe that all of the libraries are in the right places. Have other people experienced similar problems? Should I switch to OpenGL? I am using Code::Blocks. Here is what I coded (FreeType stuff is commented out). It uses SDL. #define SCREEN_WIDTH 800 #define SCREEN_HEIGHT 600 #define BALL_SIZE 20 #define BALL_X (SCREEN_WIDTH / 2) - (BALL_SIZE / 2) #define BALL_Y (SCREEN_HEIGHT / 2) - (BALL_SIZE / 2) #define PADDLE_WIDTH 20 #define PADDLE_HEIGHT 100 #define P1_X 50 #define P1_Y (SCREEN_HEIGHT / 2) - (PADDLE_HEIGHT / 2) #define P2_X (SCREEN_WIDTH - 50) - PADDLE_WIDTH #define P2_Y P1_Y #define PADDLE_SPEED 8 #include <cstdlib> #include <SDL/SDL.h> //#include <ft2build.h> //#include FT_FREETYPE_H //FT_Library library; //FT_Face face; //FT_Init_FreeType( &library ); typedef struct { int P1_x; int P1_y; int P2_x; int P2_y; int Ball_x; int Ball_y; int running; SDL_Rect Ball; SDL_Rect Paddle_1; SDL_Rect Paddle_2; int Ball_Speed_y; int Ball_Speed_x; int num_rects; SDL_Rect rects[16]; Uint32 black; Uint32 white; } Game_Data; SDL_Surface* screen = SDL_SetVideoMode(SCREEN_WIDTH, 600, 16, SDL_HWSURFACE\|SDL_DOUBLEBUF); Uint8 keystate; //TTF_Font font; void Initiate_Sprites(Game_Data game) { game->Ball_x = BALL_X; game->Ball_y = BALL_Y; game->Ball.w = BALL_SIZE; game->Ball.h = BALL_SIZE; game->Ball_Speed_y = 5; game->Ball_Speed_x = 5; game->P1_x = P1_X; game->P1_y = P1_Y; game->Paddle_1.x = P1_X; game->Paddle_1.w = PADDLE_WIDTH; game->Paddle_1.h = PADDLE_HEIGHT; game->P2_x = P2_X; game->P2_y = P2_Y; game->Paddle_2.x = P2_X; game->Paddle_2.w = PADDLE_WIDTH; game->Paddle_2.h = PADDLE_HEIGHT; } void Reset_Sprites(Game_Data game) { game->Ball.x = game->Ball_x-BALL_SIZE/2; game->Ball.y = game->Ball_y-BALL_SIZE/2; game->Ball.w = BALL_SIZE; game->Ball.h = BALL_SIZE; game->Paddle_1.y = game->P1_y; game->Paddle_1.w = PADDLE_WIDTH; game->Paddle_1.h = PADDLE_HEIGHT; game->Paddle_2.y = game->P2_y; game->Paddle_2.w = PADDLE_WIDTH; game->Paddle_2.h = PADDLE_HEIGHT; } void Draw_Sprites(Game_Data game) { int i = 0; SDL_Rect Center; Center.x = SCREEN_WIDTH/2; Center.w = 10; Center.h = 30; SDL_FillRect(screen, &(game->Paddle_1), game->white); SDL_FillRect(screen, &(game->Paddle_2), game->white); SDL_FillRect(screen, &(game->Ball), game->white); //TTF_RenderText_Solid( for (i = 0 ; i <= 9 ; i++) { Center.y = i60+30; SDL_FillRect(screen, &Center, game->white); } delete &Center; } bool Rect_Collision(SDL_Rect rect_1, SDL_Rect rect_2) { bool collide = false; if (rect_1->x <= rect_2->x) { if (rect_1->y <= rect_2->y) { if ((rect_2->x-rect_1->x) < rect_1->w) { if ((rect_2->y-rect_1->y) < rect_1->h) { collide = true; } } } if (rect_1->y > rect_2->y) { if ((rect_2->x-rect_1->x) < rect_1->w) { if ((rect_1->y-rect_2->y) < rect_2->h) { collide = true; } } } } if (rect_1->x > rect_2->x) { if (rect_1->y <= rect_2->y) { if ((rect_1->x-rect_2->x) < rect_2->w) { if ((rect_2->y-rect_1->y) < rect_1->h) { collide = true; } } } if (rect_1->y > rect_2->y) { if ((rect_1->x-rect_2->x) < rect_2->w) { if ((rect_1->y-rect_2->y) < rect_2->h) { collide = true; } } } } return collide; } void Update_Sprites(Game_Data game) { if (game->Ball_y+BALL_SIZE/2 >= SCREEN_HEIGHT) game->Ball_Speed_y = game->Ball_Speed_y-1; if (game->Ball_y-BALL_SIZE/2 <= 0) game->Ball_Speed_y = game->Ball_Speed_y-1; if (Rect_Collision(&(game->Ball), &(game->Paddle_1))) { game->Ball_Speed_x = game->Ball_Speed_x-1; } if (Rect_Collision(&(game->Ball), &(game->Paddle_2))) { game->Ball_Speed_x = game->Ball_Speed_x-1; } } void Move_Sprites(Game_Data game) { keystate = SDL_GetKeyState(NULL); if (keystate[SDLK_a]) game->P1_y = game->P1_y - PADDLE_SPEED; if (keystate[SDLK_z]) game->P1_y = game->P1_y + PADDLE_SPEED; if (keystate[SDLK_UP]) game->P2_y = game->P2_y - PADDLE_SPEED; if (keystate[SDLK_DOWN]) game->P2_y = game->P2_y + PADDLE_SPEED; game->Ball_x = game->Ball_x + game->Ball_Speed_x; game->Ball_y = game->Ball_y + game->Ball_Speed_y; } int main ( int argc, char** argv ) { Game_Data game; SDL_Event event; // initialize SDL video if ( SDL_Init( SDL_INIT_VIDEO ) < 0 ) { printf( "Unable to init SDL: %s\n", SDL_GetError() ); return 1; } /* if ( TTF_Init() < 0 ) { printf( "Unable to init TTF: %s\n", SDL_GetError() ); return 1; } / // make sure SDL cleans up before exit atexit(SDL_Quit); // create a new window game.black = SDL_MapRGB( screen->format, 0x00, 0x00, 0x00); game.white = SDL_MapRGB( screen->format, 0xff, 0xff, 0xff); Initiate_Sprites(&game); Reset_Sprites(&game); if ( !screen ) { printf("Unable to set 640x480 video: %s\n", SDL_GetError()); return 1; } SDL_WM_SetCaption( "SDL Pong", "SDL Pong" ); // load an image SDL_Surface bmp = SDL_LoadBMP("cb.bmp"); if (!bmp) { printf("Unable to load bitmap: %s\n", SDL_GetError()); return 1; } // center the bitmap on screen SDL_Rect dstrect; dstrect.x = (screen->w - bmp->w) / 2; dstrect.y = (screen->h - bmp->h) / 2; // program main loop bool done = false; while (!done) { // message processing loop SDL_Event event; while (SDL_PollEvent(&event)) { // check for messages switch (event.type) { // exit if the window is closed case SDL_QUIT: done = true; break; } // end switch } // end of message processing // DRAWING STARTS HERE Move_Sprites(&game); Reset_Sprites(&game); Update_Sprites(&game); Draw_Sprites(&game); // clear screen // SDL_FillRect(screen, 0, SDL_MapRGB(screen->format, 255, 0, 0)); // draw bitmap // SDL_BlitSurface(bmp, 0, screen, &dstrect); // DRAWING ENDS HERE SDL_Delay( 30 ); // finally, update the screen :) SDL_Flip(screen); SDL_FillRect(screen, 0, SDL_MapRGB(screen->format, 0, 0, 0)); } // end main loop // free loaded bitmap SDL_FreeSurface(bmp); // all is well ;) printf("Exited cleanly\n"); return 0; } --v There is still some of the "SDL Application" stuff in there. Please criticize/make suggestions. Does the collision function that I wrote (Rect_Collision) work?
Sun, 12 Aug 2007, 03:13
Jayenkai	In terms of your Rect_Collision code, that seems insanely complex for what it's doing! Graphics 800,600,32,2 SetBuffer BackBuffer() Type Rct Field x,y,w,h End Type a.rct=New rct a\x=100 a\y=100 a\w=600 a\h=400 p.rct=New rct p\x=100 p\y=100 p\w=32 p\h=32 Repeat Cls p\x=MouseX() p\y=MouseY() Color 255,255,255 If Rect_Collide(p.rct,a.rct) Then Color 180,0,0 Rect a\x,a\y,a\w,a\h,0 Rect p\x,p\y,p\w,p\h,0 Flip Until KeyDown(1) Function Rect_Collide(r1.rct,r2.Rct) Return r2\x+r2\w=>r1\x And r2\y+r2\h=>r1\y And r2\x<=r1\x+r1\w And r2\y<=r1\y+r1\h End Function --v As always, the easiest way to check a function, is to do it in Blitz first. The Rect_Collide check is the same as a standard "MouseIn" function, except that you add width and height to the checks. Nice and simple. -=-=- ''Load, Next List!''
Sun, 12 Aug 2007, 06:49
mike_g	Heres a pretty crude bitmap font loader I coded for SDL, I'll be working on something a bit better when I have the time: void DrawText(int x, int y, char txt) { src.w=FONT_WIDTH; src.h=FONT_HEIGHT; dest.y=y; dest.x=x; while(txt) { if(txt > ' ' && txt < '[') { src.x=((txt-' ')%FONTSET_WIDTH)FONT_WIDTH; src.y=((txt-' ')/FONTSET_WIDTH)FONT_HEIGHT; SDL_BlitSurface(font, &src, screen, &dest); } dest.x+=FONT_WIDTH; txt++; } } --v The code requires an SDL surface called 'font' to be set up. and FONT_WIDTH, and HEIGHT, are constants. Oh yeah and th if statement checks if the letter is in the font. For the one I was using I had ASCII chars from ! to Z.