SDL_Point

A structure that defines a two dimensional point.

该结构定义一个二维点

Data Fields 字段

int x the x coordinate of the point
int y the y coordinate of the point

Code Examples 代码示例

  1. // Example program:
  2. // Using SDL_Point in some places of your code
  4. #include "SDL.h"
  5. #include <stdio.h>
  7. int main(int argc, char *argv[]) {
  9.     SDL_Window *window;
  11.     SDL_Point window_position = {         //    Position of window
  12.         SDL_WINDOWPOS_CENTERED,
  13.         SDL_WINDOWPOS_CENTERED
  14.     };
  15.     SDL_Point window_size = {640, 480};   //    Size of window
  17.     SDL_Point mouse_position;             //    Mouse position coords
  19.     SDL_Init(SDL_INIT_VIDEO);             //    Initialize SDL2
  21.     // Create an application window with the following settings:
  22.     window = SDL_CreateWindow( 
  23.         "SDL_Point usage",                //    window title
  24.         window_position.x,                //    initial x position
  25.         window_position.y,                //    initial y position
  26.         window_size.x,                    //    width, in pixels
  27.         window_size.y,                    //    height, in pixels
  28.         SDL_WINDOW_OPENGL                 //    flags - see below
  29.     );
  31.     // Check that the window was successfully made
  32.     if (window == NULL) {
  33.         SDL_Log("Could not create window: %s", SDL_GetError());
  34.         return 1;
  35.     }
  37.     SDL_GetMouseState(                    //    Sets mouse_position to...
  38.         &mouse_position.x,                // ...mouse arrow coords on window
  39.         &mouse_position.y
  40.     );
  42.     SDL_Log("Mouse position: x=%i y=%i",  //    Print mouse position
  43.          mouse_position.x, mouse_position.y
  44.     );
  46.     // Close and destroy the window
  47.     SDL_DestroyWindow(window); 
  49.     // Clean up
  50.     SDL_Quit();
  51.     return 0; 
  52. }

Remarks 注意

An SDL_Point defines single two dimensional point. It can be used not only for points, but also for size. SDL_Point is used by SDL_EnclosePoints() to check if array of points is inside rectangle (SDL_Rect). You can also make your own functions using SDL_Point to simplify your code, it’s very helpful.

一个SDL_Point结构定义了一个二维的点。但它不仅可以用来表示点，也可以用来表示大小。SDL_Point也在函数SDL_EnclosePoints()中被用来检查一组点是否在一个矩形(SDL_Rect)之内。你也可以在你自己的函数中使用现成的SDL_Point来简化代码，这往往很有用。

Related Structures 相关结构

SDL_Rect

Related Functions 相关函数

SDL_EnclosePoints()