SDL  2.0
testscale.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_test_common.h"
23 
24 #define WINDOW_WIDTH 640
25 #define WINDOW_HEIGHT 480
26 
28 
29 typedef struct {
34  SDL_Rect sprite_rect;
35  int scale_direction;
36 } DrawState;
37 
39 int done;
40 
41 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
42 static void
43 quit(int rc)
44 {
45  SDLTest_CommonQuit(state);
46  exit(rc);
47 }
48 
50 LoadTexture(SDL_Renderer *renderer, char *file, SDL_bool transparent)
51 {
52  SDL_Surface *temp;
54 
55  /* Load the sprite image */
56  temp = SDL_LoadBMP(file);
57  if (temp == NULL) {
58  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't load %s: %s", file, SDL_GetError());
59  return NULL;
60  }
61 
62  /* Set transparent pixel as the pixel at (0,0) */
63  if (transparent) {
64  if (temp->format->palette) {
65  SDL_SetColorKey(temp, SDL_TRUE, *(Uint8 *) temp->pixels);
66  } else {
67  switch (temp->format->BitsPerPixel) {
68  case 15:
70  (*(Uint16 *) temp->pixels) & 0x00007FFF);
71  break;
72  case 16:
73  SDL_SetColorKey(temp, SDL_TRUE, *(Uint16 *) temp->pixels);
74  break;
75  case 24:
77  (*(Uint32 *) temp->pixels) & 0x00FFFFFF);
78  break;
79  case 32:
80  SDL_SetColorKey(temp, SDL_TRUE, *(Uint32 *) temp->pixels);
81  break;
82  }
83  }
84  }
85 
86  /* Create textures from the image */
87  texture = SDL_CreateTextureFromSurface(renderer, temp);
88  if (!texture) {
89  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create texture: %s\n", SDL_GetError());
90  SDL_FreeSurface(temp);
91  return NULL;
92  }
93  SDL_FreeSurface(temp);
94 
95  /* We're ready to roll. :) */
96  return texture;
97 }
98 
99 void
101 {
103 
104  SDL_RenderGetViewport(s->renderer, &viewport);
105 
106  /* Draw the background */
108 
109  /* Scale and draw the sprite */
110  s->sprite_rect.w += s->scale_direction;
111  s->sprite_rect.h += s->scale_direction;
112  if (s->scale_direction > 0) {
113  if (s->sprite_rect.w >= viewport.w || s->sprite_rect.h >= viewport.h) {
114  s->scale_direction = -1;
115  }
116  } else {
117  if (s->sprite_rect.w <= 1 || s->sprite_rect.h <= 1) {
118  s->scale_direction = 1;
119  }
120  }
121  s->sprite_rect.x = (viewport.w - s->sprite_rect.w) / 2;
122  s->sprite_rect.y = (viewport.h - s->sprite_rect.h) / 2;
123 
125 
126  /* Update the screen! */
128 }
129 
130 void
132 {
133  int i;
135 
136  /* Check for events */
137  while (SDL_PollEvent(&event)) {
138  SDLTest_CommonEvent(state, &event, &done);
139  }
140  for (i = 0; i < state->num_windows; ++i) {
141  if (state->windows[i] == NULL)
142  continue;
143  Draw(&drawstates[i]);
144  }
145 #ifdef __EMSCRIPTEN__
146  if (done) {
147  emscripten_cancel_main_loop();
148  }
149 #endif
150 }
151 
152 int
153 main(int argc, char *argv[])
154 {
155  int i;
156  int frames;
157  Uint32 then, now;
158 
159  /* Enable standard application logging */
161 
162  /* Initialize test framework */
164  if (!state) {
165  return 1;
166  }
167  for (i = 1; i < argc;) {
168  int consumed;
169 
170  consumed = SDLTest_CommonArg(state, i);
171  if (consumed == 0) {
172  SDL_Log("Usage: %s %s\n", argv[0], SDLTest_CommonUsage(state));
173  return 1;
174  }
175  i += consumed;
176  }
177  if (!SDLTest_CommonInit(state)) {
178  quit(2);
179  }
180 
181  drawstates = SDL_stack_alloc(DrawState, state->num_windows);
182  for (i = 0; i < state->num_windows; ++i) {
183  DrawState *drawstate = &drawstates[i];
184 
185  drawstate->window = state->windows[i];
186  drawstate->renderer = state->renderers[i];
187  drawstate->sprite = LoadTexture(drawstate->renderer, "icon.bmp", SDL_TRUE);
188  drawstate->background = LoadTexture(drawstate->renderer, "sample.bmp", SDL_FALSE);
189  if (!drawstate->sprite || !drawstate->background) {
190  quit(2);
191  }
192  SDL_QueryTexture(drawstate->sprite, NULL, NULL,
193  &drawstate->sprite_rect.w, &drawstate->sprite_rect.h);
194  drawstate->scale_direction = 1;
195  }
196 
197  /* Main render loop */
198  frames = 0;
199  then = SDL_GetTicks();
200  done = 0;
201 
202 #ifdef __EMSCRIPTEN__
203  emscripten_set_main_loop(loop, 0, 1);
204 #else
205  while (!done) {
206  ++frames;
207  loop();
208  }
209 #endif
210 
211  /* Print out some timing information */
212  now = SDL_GetTicks();
213  if (now > then) {
214  double fps = ((double) frames * 1000) / (now - then);
215  SDL_Log("%2.2f frames per second\n", fps);
216  }
217 
218  SDL_stack_free(drawstates);
219 
220  quit(0);
221  return 0;
222 }
223 
224 /* vi: set ts=4 sw=4 expandtab: */
SDL_Renderer * renderer
#define SDL_PollEvent
#define SDL_GetError
SDL_Rect sprite_rect
GLdouble s
Definition: SDL_opengl.h:2063
#define SDL_LoadBMP(file)
Definition: SDL_surface.h:200
SDLTest_CommonState * SDLTest_CommonCreateState(char **argv, Uint32 flags)
Parse command line parameters and create common state.
int SDLTest_CommonArg(SDLTest_CommonState *state, int index)
Process one common argument.
A collection of pixels used in software blitting.
Definition: SDL_surface.h:69
static SDLTest_CommonState * state
Definition: testscale.c:27
SDL_Texture * background
uint32_t Uint32
Definition: SDL_stdinc.h:181
SDL_bool SDLTest_CommonInit(SDLTest_CommonState *state)
Open test window.
SDL_Window * window
SDL_Texture * LoadTexture(SDL_Renderer *renderer, char *file, SDL_bool transparent)
Definition: testscale.c:50
SDL_Window ** windows
#define SDL_LogError
#define SDL_RenderCopy
#define SDL_Log
DrawState * drawstates
Definition: testscale.c:38
GLenum GLenum GLuint texture
#define SDL_CreateTextureFromSurface
void SDLTest_CommonEvent(SDLTest_CommonState *state, SDL_Event *event, int *done)
Common event handler for test windows.
Uint32 SDL_GetTicks(void)
Get the number of milliseconds since the SDL library initialization.
void * pixels
Definition: SDL_surface.h:75
#define SDL_FreeSurface
static SDL_Renderer * renderer
uint8_t Uint8
Definition: SDL_stdinc.h:157
#define SDL_stack_alloc(type, count)
Definition: SDL_stdinc.h:354
struct _cl_event * event
Uint8 BitsPerPixel
Definition: SDL_pixels.h:319
void Draw(DrawState *s)
Definition: testscale.c:100
#define SDL_QueryTexture
#define SDL_RenderGetViewport
#define SDL_SetColorKey
int x
Definition: SDL_rect.h:66
const char * SDLTest_CommonUsage(SDLTest_CommonState *state)
Returns common usage information.
void loop()
Definition: testscale.c:131
int w
Definition: SDL_rect.h:67
SDL_Renderer ** renderers
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
int main(int argc, char *argv[])
Definition: testscale.c:153
#define NULL
Definition: begin_code.h:164
SDL_bool
Definition: SDL_stdinc.h:139
SDL_PixelFormat * format
Definition: SDL_surface.h:72
static void quit(int rc)
Definition: testscale.c:43
EGLSurface EGLNativeWindowType * window
Definition: eglext.h:1025
int h
Definition: SDL_rect.h:67
static SDL_Texture * sprite
The type used to identify a window.
Definition: SDL_sysvideo.h:73
SDL_Rect viewport
Definition: testviewport.c:28
SDL_Texture * sprite
uint16_t Uint16
Definition: SDL_stdinc.h:169
int done
Definition: testscale.c:39
General event structure.
Definition: SDL_events.h:525
SDL_Palette * palette
Definition: SDL_pixels.h:318
SDL_Texture * background
#define SDL_stack_free(data)
Definition: SDL_stdinc.h:355
int y
Definition: SDL_rect.h:66
void SDLTest_CommonQuit(SDLTest_CommonState *state)
Close test window.
#define SDL_INIT_VIDEO
Definition: SDL.h:78
A rectangle, with the origin at the upper left.
Definition: SDL_rect.h:64
#define SDL_RenderPresent