我正在开发一款游戏,而我似乎无法画出屏幕。当我调用SDL_BlitSurface时,没有任何反应。但是,它不返回错误代码。我编写了一个类来处理图像精灵,当我用调试器进行扫描时,我发现它正在返回表面的非空值,以便传输到主视频表面。但是,当我打电话给我的绘图功能时,它什么都不做。我已经确认像素值完全不会改变表面。我究竟做错了什么?SDL_BlitSurface()没有效果
这里是我的main.cpp:
//Standard libs
#include <SDL.h>
//Our gaming base
#include "game_base.h"
//SDL redefines main as winmain, but this is a console application so we don't want that
#undef main
const int MAX_FPS = 80;
int main (int argc, char* argv[]) {
//Initialization
System game(false, 640, 480, "Platformer", MAX_FPS); //Create a game that is not fullscreen with a resolution of 640x480
SDL_Surface *buffer = NULL;
Input *input = NULL;
buffer = game.get_buffer();
Image_Sprite *player_sprite = NULL;
player_sprite = new Image_Sprite("data/player.bmp", 1, 4);
SDL_Rect hitbox;
hitbox.w = 32;
hitbox.h = 32;
hitbox.x = 0;
hitbox.y = 0;
Player player(100, 100, hitbox, 1.0, RIGHT, player_sprite);
//Main game loop
while(!game.check_is_done()) {
game.refresh_top();
player.draw(buffer);
game.refresh_bottom();
}
//Cleanup
delete input;
delete player_sprite;
}
这是我使用的绘制函数:
void Character::draw(SDL_Surface *destination) {
SDL_Rect coordinates;
SDL_Surface *sprite;
sprite = my_sprite->get_frame(my_frame, my_direction);
coordinates.x = (int)get_x();
coordinates.y = (int)get_y();
SDL_BlitSurface(sprite, NULL, destination, NULL);
}
最后,这里是纽约get_frame()函数:
SDL_Surface* Image_Sprite::get_frame(int x, int y) {
SDL_PixelFormat *format;
format = my_sprite->format;
SDL_Surface *frame = SDL_CreateRGBSurface(my_sprite->flags, my_frame_width, my_frame_height, format->BitsPerPixel,
format->Rmask, format->Gmask, format->Bmask, format->Amask);
SDL_Rect *frame_crop = new SDL_Rect;
frame_crop->x = my_frame_width * x;
frame_crop->y = my_frame_height * y;
frame_crop->w = my_frame_width;
frame_crop->h = my_frame_height;
SDL_Rect *coordinates = new SDL_Rect;
coordinates->x = 0;
coordinates->y = 0;
SDL_BlitSurface(my_sprite, frame_crop, frame, coordinates);
delete frame_crop;
return frame;
}
SDL_Flip(buffer)是System :: refresh_bottom()的一部分。我很抱歉如果我没有说清楚。 – 2012-04-09 23:29:35