SDL 2.0
testspriteminimal.c
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1/*
2 Copyright (C) 1997-2019 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
32static int sprite_w, sprite_h;
33
35int done;
36
37/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
38static void
39quit(int rc)
40{
41 exit(rc);
42}
43
44int
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 */
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
93void
95{
96 int i;
99 SDL_Rect *position, *velocity;
100
101 /* Draw a gray background */
102 SDL_SetRenderDrawColor(renderer, 0xA0, 0xA0, 0xA0, 0xFF);
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! */
126}
127
128void 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 }
139#ifdef __EMSCRIPTEN__
140 if (done) {
141 emscripten_cancel_main_loop();
142 }
143#endif
144}
145
146int
147main(int argc, char *argv[])
148{
150 int i;
151
152
153 /* Enable standard application logging */
155
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);
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 SDL_RenderPresent
#define SDL_SetColorKey
#define SDL_GetError
#define SDL_PollEvent
#define SDL_SetRenderDrawColor
#define SDL_CreateTextureFromSurface
#define SDL_LogSetPriority
#define SDL_RenderClear
#define SDL_LogError
#define SDL_RenderCopy
#define SDL_FreeSurface
#define SDL_CreateWindowAndRenderer
@ SDL_QUIT
Definition: SDL_events.h:60
@ SDL_KEYDOWN
Definition: SDL_events.h:96
@ SDL_LOG_PRIORITY_INFO
Definition: SDL_log.h:106
@ SDL_LOG_CATEGORY_APPLICATION
Definition: SDL_log.h:66
GLint GLint GLint GLint GLint GLint y
Definition: SDL_opengl.h:1574
GLint GLint GLint GLint GLint x
Definition: SDL_opengl.h:1574
struct _cl_event * event
@ SDL_TRUE
Definition: SDL_stdinc.h:164
uint32_t Uint32
Definition: SDL_stdinc.h:203
uint16_t Uint16
Definition: SDL_stdinc.h:191
uint8_t Uint8
Definition: SDL_stdinc.h:179
#define SDL_LoadBMP(file)
Definition: SDL_surface.h:201
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 NULL
Definition: begin_code.h:167
EGLSurface EGLnsecsANDROID time
Definition: eglext.h:518
EGLSurface EGLNativeWindowType * window
Definition: eglext.h:1025
Uint8 BitsPerPixel
Definition: SDL_pixels.h:319
SDL_Palette * palette
Definition: SDL_pixels.h:318
A rectangle, with the origin at the upper left (integer).
Definition: SDL_rect.h:78
int h
Definition: SDL_rect.h:80
int w
Definition: SDL_rect.h:80
int y
Definition: SDL_rect.h:79
int x
Definition: SDL_rect.h:79
A collection of pixels used in software blitting.
Definition: SDL_surface.h:71
SDL_PixelFormat * format
Definition: SDL_surface.h:73
void * pixels
Definition: SDL_surface.h:76
The type used to identify a window.
Definition: SDL_sysvideo.h:74
int window_w
Definition: testoverlay2.c:143
int window_h
Definition: testoverlay2.c:144
int main(int argc, char *argv[])
static int sprite_w
static SDL_Rect velocities[NUM_SPRITES]
static void quit(int rc)
static SDL_Rect positions[NUM_SPRITES]
#define WINDOW_WIDTH
#define WINDOW_HEIGHT
int done
int LoadSprite(char *file, SDL_Renderer *renderer)
SDL_Renderer * renderer
static SDL_Texture * sprite
static int sprite_h
#define NUM_SPRITES
#define MAX_SPEED
void MoveSprites(SDL_Renderer *renderer, SDL_Texture *sprite)
void loop()
General event structure.
Definition: SDL_events.h:558