SDL  2.0
testspriteminimal.c
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1 /*
2  Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
3 
4  This software is provided 'as-is', without any express or implied
5  warranty. In no event will the authors be held liable for any damages
6  arising from the use of this software.
7 
8  Permission is granted to anyone to use this software for any purpose,
9  including commercial applications, and to alter it and redistribute it
10  freely.
11 */
12 /* Simple program: Move N sprites around on the screen as fast as possible */
13 
14 #include <stdlib.h>
15 #include <stdio.h>
16 #include <time.h>
17 
18 #ifdef __EMSCRIPTEN__
19 #include <emscripten/emscripten.h>
20 #endif
21 
22 #include "SDL.h"
23 
24 #define WINDOW_WIDTH 640
25 #define WINDOW_HEIGHT 480
26 #define NUM_SPRITES 100
27 #define MAX_SPEED 1
28 
32 static int sprite_w, sprite_h;
33 
35 int done;
36 
37 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
38 static void
39 quit(int rc)
40 {
41  exit(rc);
42 }
43 
44 int
45 LoadSprite(char *file, SDL_Renderer *renderer)
46 {
47  SDL_Surface *temp;
48 
49  /* Load the sprite image */
50  temp = SDL_LoadBMP(file);
51  if (temp == NULL) {
52  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't load %s: %s\n", file, SDL_GetError());
53  return (-1);
54  }
55  sprite_w = temp->w;
56  sprite_h = temp->h;
57 
58  /* Set transparent pixel as the pixel at (0,0) */
59  if (temp->format->palette) {
60  SDL_SetColorKey(temp, SDL_TRUE, *(Uint8 *) temp->pixels);
61  } else {
62  switch (temp->format->BitsPerPixel) {
63  case 15:
65  (*(Uint16 *) temp->pixels) & 0x00007FFF);
66  break;
67  case 16:
68  SDL_SetColorKey(temp, SDL_TRUE, *(Uint16 *) temp->pixels);
69  break;
70  case 24:
72  (*(Uint32 *) temp->pixels) & 0x00FFFFFF);
73  break;
74  case 32:
75  SDL_SetColorKey(temp, SDL_TRUE, *(Uint32 *) temp->pixels);
76  break;
77  }
78  }
79 
80  /* Create textures from the image */
81  sprite = SDL_CreateTextureFromSurface(renderer, temp);
82  if (!sprite) {
83  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create texture: %s\n", SDL_GetError());
84  SDL_FreeSurface(temp);
85  return (-1);
86  }
87  SDL_FreeSurface(temp);
88 
89  /* We're ready to roll. :) */
90  return (0);
91 }
92 
93 void
94 MoveSprites(SDL_Renderer * renderer, SDL_Texture * sprite)
95 {
96  int i;
97  int window_w = WINDOW_WIDTH;
98  int window_h = WINDOW_HEIGHT;
99  SDL_Rect *position, *velocity;
100 
101  /* Draw a gray background */
102  SDL_SetRenderDrawColor(renderer, 0xA0, 0xA0, 0xA0, 0xFF);
103  SDL_RenderClear(renderer);
104 
105  /* Move the sprite, bounce at the wall, and draw */
106  for (i = 0; i < NUM_SPRITES; ++i) {
107  position = &positions[i];
108  velocity = &velocities[i];
109  position->x += velocity->x;
110  if ((position->x < 0) || (position->x >= (window_w - sprite_w))) {
111  velocity->x = -velocity->x;
112  position->x += velocity->x;
113  }
114  position->y += velocity->y;
115  if ((position->y < 0) || (position->y >= (window_h - sprite_h))) {
116  velocity->y = -velocity->y;
117  position->y += velocity->y;
118  }
119 
120  /* Blit the sprite onto the screen */
121  SDL_RenderCopy(renderer, sprite, NULL, position);
122  }
123 
124  /* Update the screen! */
125  SDL_RenderPresent(renderer);
126 }
127 
128 void loop()
129 {
131 
132  /* Check for events */
133  while (SDL_PollEvent(&event)) {
134  if (event.type == SDL_QUIT || event.type == SDL_KEYDOWN) {
135  done = 1;
136  }
137  }
138  MoveSprites(renderer, sprite);
139 #ifdef __EMSCRIPTEN__
140  if (done) {
141  emscripten_cancel_main_loop();
142  }
143 #endif
144 }
145 
146 int
147 main(int argc, char *argv[])
148 {
150  int i;
151 
152 
153  /* Enable standard application logging */
155 
156  if (SDL_CreateWindowAndRenderer(WINDOW_WIDTH, WINDOW_HEIGHT, 0, &window, &renderer) < 0) {
157  quit(2);
158  }
159 
160  if (LoadSprite("icon.bmp", renderer) < 0) {
161  quit(2);
162  }
163 
164  /* Initialize the sprite positions */
165  srand(time(NULL));
166  for (i = 0; i < NUM_SPRITES; ++i) {
167  positions[i].x = rand() % (WINDOW_WIDTH - sprite_w);
168  positions[i].y = rand() % (WINDOW_HEIGHT - sprite_h);
169  positions[i].w = sprite_w;
170  positions[i].h = sprite_h;
171  velocities[i].x = 0;
172  velocities[i].y = 0;
173  while (!velocities[i].x && !velocities[i].y) {
174  velocities[i].x = (rand() % (MAX_SPEED * 2 + 1)) - MAX_SPEED;
175  velocities[i].y = (rand() % (MAX_SPEED * 2 + 1)) - MAX_SPEED;
176  }
177  }
178 
179  /* Main render loop */
180  done = 0;
181 
182 #ifdef __EMSCRIPTEN__
183  emscripten_set_main_loop(loop, 0, 1);
184 #else
185  while (!done) {
186  loop();
187  }
188 #endif
189  quit(0);
190 
191  return 0; /* to prevent compiler warning */
192 }
193 
194 /* vi: set ts=4 sw=4 expandtab: */
#define NUM_SPRITES
#define SDL_PollEvent
#define SDL_GetError
EGLSurface EGLnsecsANDROID time
Definition: eglext.h:518
int LoadSprite(char *file, SDL_Renderer *renderer)
#define SDL_LoadBMP(file)
Definition: SDL_surface.h:200
GLint GLint GLint GLint GLint x
Definition: SDL_opengl.h:1574
void loop()
static SDL_Rect velocities[NUM_SPRITES]
A collection of pixels used in software blitting.
Definition: SDL_surface.h:69
void MoveSprites(SDL_Renderer *renderer, SDL_Texture *sprite)
static int sprite_w
uint32_t Uint32
Definition: SDL_stdinc.h:181
#define MAX_SPEED
SDL_Renderer * renderer
static int sprite_h
#define SDL_LogError
#define SDL_RenderCopy
static SDL_Rect positions[NUM_SPRITES]
#define SDL_CreateTextureFromSurface
void * pixels
Definition: SDL_surface.h:75
#define SDL_FreeSurface
uint8_t Uint8
Definition: SDL_stdinc.h:157
struct _cl_event * event
Uint8 BitsPerPixel
Definition: SDL_pixels.h:319
#define SDL_SetColorKey
GLint GLint GLint GLint GLint GLint y
Definition: SDL_opengl.h:1574
int x
Definition: SDL_rect.h:66
#define WINDOW_WIDTH
int main(int argc, char *argv[])
int w
Definition: SDL_rect.h:67
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50
#define SDL_LogSetPriority
#define NULL
Definition: begin_code.h:164
SDL_PixelFormat * format
Definition: SDL_surface.h:72
#define SDL_RenderClear
EGLSurface EGLNativeWindowType * window
Definition: eglext.h:1025
int h
Definition: SDL_rect.h:67
static SDL_Texture * sprite
#define WINDOW_HEIGHT
The type used to identify a window.
Definition: SDL_sysvideo.h:73
#define SDL_CreateWindowAndRenderer
int done
int window_h
Definition: testoverlay2.c:144
uint16_t Uint16
Definition: SDL_stdinc.h:169
General event structure.
Definition: SDL_events.h:525
#define SDL_SetRenderDrawColor
SDL_Palette * palette
Definition: SDL_pixels.h:318
int y
Definition: SDL_rect.h:66
int window_w
Definition: testoverlay2.c:143
A rectangle, with the origin at the upper left.
Definition: SDL_rect.h:64
#define SDL_RenderPresent
Uint32 type
Definition: SDL_events.h:527
static void quit(int rc)