This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
testspriteminimal.c
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/* Simple program: Move N sprites around on the screen as fast as possible */
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
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#include "SDL.h"
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#define WINDOW_WIDTH 640
#define WINDOW_HEIGHT 480
#define NUM_SPRITES 100
#define MAX_SPEED 1
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static SDL_Texture *sprite;
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static SDL_Rect positions[NUM_SPRITES];
static SDL_Rect velocities[NUM_SPRITES];
static int sprite_w, sprite_h;
/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void
quit(int rc)
{
exit(rc);
}
int
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LoadSprite(char *file, SDL_Renderer *renderer)
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{
SDL_Surface *temp;
/* Load the sprite image */
temp = SDL_LoadBMP(file);
if (temp == NULL) {
fprintf(stderr, "Couldn't load %s: %s", file, SDL_GetError());
return (-1);
}
sprite_w = temp->w;
sprite_h = temp->h;
/* Set transparent pixel as the pixel at (0,0) */
if (temp->format->palette) {
SDL_SetColorKey(temp, SDL_TRUE, *(Uint8 *) temp->pixels);
} else {
switch (temp->format->BitsPerPixel) {
case 15:
SDL_SetColorKey(temp, SDL_TRUE,
(*(Uint16 *) temp->pixels) & 0x00007FFF);
break;
case 16:
SDL_SetColorKey(temp, SDL_TRUE, *(Uint16 *) temp->pixels);
break;
case 24:
SDL_SetColorKey(temp, SDL_TRUE,
(*(Uint32 *) temp->pixels) & 0x00FFFFFF);
break;
case 32:
SDL_SetColorKey(temp, SDL_TRUE, *(Uint32 *) temp->pixels);
break;
}
}
/* Create textures from the image */
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sprite = SDL_CreateTextureFromSurface(renderer, temp);
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if (!sprite) {
fprintf(stderr, "Couldn't create texture: %s\n", SDL_GetError());
SDL_FreeSurface(temp);
return (-1);
}
SDL_FreeSurface(temp);
/* We're ready to roll. :) */
return (0);
}
void
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MoveSprites(SDL_Window * window, SDL_Renderer * renderer, SDL_Texture * sprite)
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{
int i;
int window_w = WINDOW_WIDTH;
int window_h = WINDOW_HEIGHT;
SDL_Rect *position, *velocity;
/* Draw a gray background */
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SDL_SetRenderDrawColor(renderer, 0xA0, 0xA0, 0xA0, 0xFF);
SDL_RenderClear(renderer);
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/* Move the sprite, bounce at the wall, and draw */
for (i = 0; i < NUM_SPRITES; ++i) {
position = &positions[i];
velocity = &velocities[i];
position->x += velocity->x;
if ((position->x < 0) || (position->x >= (window_w - sprite_w))) {
velocity->x = -velocity->x;
position->x += velocity->x;
}
position->y += velocity->y;
if ((position->y < 0) || (position->y >= (window_h - sprite_h))) {
velocity->y = -velocity->y;
position->y += velocity->y;
}
/* Blit the sprite onto the screen */
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SDL_RenderCopy(renderer, sprite, NULL, position);
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}
/* Update the screen! */
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SDL_RenderPresent(renderer);
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}
int
main(int argc, char *argv[])
{
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SDL_Window *window;
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SDL_Renderer *renderer;
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int i, done;
SDL_Event event;
window = SDL_CreateWindow("Happy Smileys",
SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED,
WINDOW_WIDTH, WINDOW_HEIGHT,
SDL_WINDOW_SHOWN);
if (!window) {
quit(2);
}
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renderer = SDL_CreateRenderer(window, -1, 0);
if (!renderer) {
quit(2);
}
if (LoadSprite("icon.bmp", renderer) < 0) {
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quit(2);
}
/* Initialize the sprite positions */
srand(time(NULL));
for (i = 0; i < NUM_SPRITES; ++i) {
positions[i].x = rand() % (WINDOW_WIDTH - sprite_w);
positions[i].y = rand() % (WINDOW_HEIGHT - sprite_h);
positions[i].w = sprite_w;
positions[i].h = sprite_h;
velocities[i].x = 0;
velocities[i].y = 0;
while (!velocities[i].x && !velocities[i].y) {
velocities[i].x = (rand() % (MAX_SPEED * 2 + 1)) - MAX_SPEED;
velocities[i].y = (rand() % (MAX_SPEED * 2 + 1)) - MAX_SPEED;
}
}
/* Main render loop */
done = 0;
while (!done) {
/* Check for events */
while (SDL_PollEvent(&event)) {
if (event.type == SDL_QUIT || event.type == SDL_KEYDOWN) {
done = 1;
}
}
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MoveSprites(window, renderer, sprite);
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}
quit(0);
}
/* vi: set ts=4 sw=4 expandtab: */