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      1 /*
      2  * Copyright (C) 2010 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 #include <jni.h>
     18 #include <time.h>
     19 #include <android/log.h>
     20 #include <android/bitmap.h>
     21 
     22 #include <stdio.h>
     23 #include <stdlib.h>
     24 #include <math.h>
     25 
     26 #define  LOG_TAG    "libplasma"
     27 #define  LOGI(...)  __android_log_print(ANDROID_LOG_INFO,LOG_TAG,__VA_ARGS__)
     28 #define  LOGE(...)  __android_log_print(ANDROID_LOG_ERROR,LOG_TAG,__VA_ARGS__)
     29 
     30 /* Set to 1 to enable debug log traces. */
     31 #define DEBUG 0
     32 
     33 /* Set to 1 to optimize memory stores when generating plasma. */
     34 #define OPTIMIZE_WRITES  1
     35 
     36 /* Return current time in milliseconds */
     37 static double now_ms(void)
     38 {
     39     struct timeval tv;
     40     gettimeofday(&tv, NULL);
     41     return tv.tv_sec*1000. + tv.tv_usec/1000.;
     42 }
     43 
     44 /* We're going to perform computations for every pixel of the target
     45  * bitmap. floating-point operations are very slow on ARMv5, and not
     46  * too bad on ARMv7 with the exception of trigonometric functions.
     47  *
     48  * For better performance on all platforms, we're going to use fixed-point
     49  * arithmetic and all kinds of tricks
     50  */
     51 
     52 typedef int32_t  Fixed;
     53 
     54 #define  FIXED_BITS           16
     55 #define  FIXED_ONE            (1 << FIXED_BITS)
     56 #define  FIXED_AVERAGE(x,y)   (((x) + (y)) >> 1)
     57 
     58 #define  FIXED_FROM_INT(x)    ((x) << FIXED_BITS)
     59 #define  FIXED_TO_INT(x)      ((x) >> FIXED_BITS)
     60 
     61 #define  FIXED_FROM_FLOAT(x)  ((Fixed)((x)*FIXED_ONE))
     62 #define  FIXED_TO_FLOAT(x)    ((x)/(1.*FIXED_ONE))
     63 
     64 #define  FIXED_MUL(x,y)       (((int64_t)(x) * (y)) >> FIXED_BITS)
     65 #define  FIXED_DIV(x,y)       (((int64_t)(x) * FIXED_ONE) / (y))
     66 
     67 #define  FIXED_DIV2(x)        ((x) >> 1)
     68 #define  FIXED_AVERAGE(x,y)   (((x) + (y)) >> 1)
     69 
     70 #define  FIXED_FRAC(x)        ((x) & ((1 << FIXED_BITS)-1))
     71 #define  FIXED_TRUNC(x)       ((x) & ~((1 << FIXED_BITS)-1))
     72 
     73 #define  FIXED_FROM_INT_FLOAT(x,f)   (Fixed)((x)*(FIXED_ONE*(f)))
     74 
     75 typedef int32_t  Angle;
     76 
     77 #define  ANGLE_BITS              9
     78 
     79 #if ANGLE_BITS < 8
     80 #  error ANGLE_BITS must be at least 8
     81 #endif
     82 
     83 #define  ANGLE_2PI               (1 << ANGLE_BITS)
     84 #define  ANGLE_PI                (1 << (ANGLE_BITS-1))
     85 #define  ANGLE_PI2               (1 << (ANGLE_BITS-2))
     86 #define  ANGLE_PI4               (1 << (ANGLE_BITS-3))
     87 
     88 #define  ANGLE_FROM_FLOAT(x)   (Angle)((x)*ANGLE_PI/M_PI)
     89 #define  ANGLE_TO_FLOAT(x)     ((x)*M_PI/ANGLE_PI)
     90 
     91 #if ANGLE_BITS <= FIXED_BITS
     92 #  define  ANGLE_FROM_FIXED(x)     (Angle)((x) >> (FIXED_BITS - ANGLE_BITS))
     93 #  define  ANGLE_TO_FIXED(x)       (Fixed)((x) << (FIXED_BITS - ANGLE_BITS))
     94 #else
     95 #  define  ANGLE_FROM_FIXED(x)     (Angle)((x) << (ANGLE_BITS - FIXED_BITS))
     96 #  define  ANGLE_TO_FIXED(x)       (Fixed)((x) >> (ANGLE_BITS - FIXED_BITS))
     97 #endif
     98 
     99 static Fixed  angle_sin_tab[ANGLE_2PI+1];
    100 
    101 static void init_angles(void)
    102 {
    103     int  nn;
    104     for (nn = 0; nn < ANGLE_2PI+1; nn++) {
    105         double  radians = nn*M_PI/ANGLE_PI;
    106         angle_sin_tab[nn] = FIXED_FROM_FLOAT(sin(radians));
    107     }
    108 }
    109 
    110 static __inline__ Fixed angle_sin( Angle  a )
    111 {
    112     return angle_sin_tab[(uint32_t)a & (ANGLE_2PI-1)];
    113 }
    114 
    115 static __inline__ Fixed angle_cos( Angle  a )
    116 {
    117     return angle_sin(a + ANGLE_PI2);
    118 }
    119 
    120 static __inline__ Fixed fixed_sin( Fixed  f )
    121 {
    122     return angle_sin(ANGLE_FROM_FIXED(f));
    123 }
    124 
    125 static __inline__ Fixed  fixed_cos( Fixed  f )
    126 {
    127     return angle_cos(ANGLE_FROM_FIXED(f));
    128 }
    129 
    130 /* Color palette used for rendering the plasma */
    131 #define  PALETTE_BITS   8
    132 #define  PALETTE_SIZE   (1 << PALETTE_BITS)
    133 
    134 #if PALETTE_BITS > FIXED_BITS
    135 #  error PALETTE_BITS must be smaller than FIXED_BITS
    136 #endif
    137 
    138 static uint16_t  palette[PALETTE_SIZE];
    139 
    140 static uint16_t  make565(int red, int green, int blue)
    141 {
    142     return (uint16_t)( ((red   << 8) & 0xf800) |
    143                        ((green << 2) & 0x03e0) |
    144                        ((blue  >> 3) & 0x001f) );
    145 }
    146 
    147 static void init_palette(void)
    148 {
    149     int  nn, mm = 0;
    150     /* fun with colors */
    151     for (nn = 0; nn < PALETTE_SIZE/4; nn++) {
    152         int  jj = (nn-mm)*4*255/PALETTE_SIZE;
    153         palette[nn] = make565(255, jj, 255-jj);
    154     }
    155 
    156     for ( mm = nn; nn < PALETTE_SIZE/2; nn++ ) {
    157         int  jj = (nn-mm)*4*255/PALETTE_SIZE;
    158         palette[nn] = make565(255-jj, 255, jj);
    159     }
    160 
    161     for ( mm = nn; nn < PALETTE_SIZE*3/4; nn++ ) {
    162         int  jj = (nn-mm)*4*255/PALETTE_SIZE;
    163         palette[nn] = make565(0, 255-jj, 255);
    164     }
    165 
    166     for ( mm = nn; nn < PALETTE_SIZE; nn++ ) {
    167         int  jj = (nn-mm)*4*255/PALETTE_SIZE;
    168         palette[nn] = make565(jj, 0, 255);
    169     }
    170 }
    171 
    172 static __inline__ uint16_t  palette_from_fixed( Fixed  x )
    173 {
    174     if (x < 0) x = -x;
    175     if (x >= FIXED_ONE) x = FIXED_ONE-1;
    176     int  idx = FIXED_FRAC(x) >> (FIXED_BITS - PALETTE_BITS);
    177     return palette[idx & (PALETTE_SIZE-1)];
    178 }
    179 
    180 /* Angles expressed as fixed point radians */
    181 
    182 static void init_tables(void)
    183 {
    184     init_palette();
    185     init_angles();
    186 }
    187 
    188 static void fill_plasma( AndroidBitmapInfo*  info, void*  pixels, double  t )
    189 {
    190     Fixed ft  = FIXED_FROM_FLOAT(t/1000.);
    191     Fixed yt1 = FIXED_FROM_FLOAT(t/1230.);
    192     Fixed yt2 = yt1;
    193     Fixed xt10 = FIXED_FROM_FLOAT(t/3000.);
    194     Fixed xt20 = xt10;
    195 
    196 #define  YT1_INCR   FIXED_FROM_FLOAT(1/100.)
    197 #define  YT2_INCR   FIXED_FROM_FLOAT(1/163.)
    198 
    199     int  yy;
    200     for (yy = 0; yy < info->height; yy++) {
    201         uint16_t*  line = (uint16_t*)pixels;
    202         Fixed      base = fixed_sin(yt1) + fixed_sin(yt2);
    203         Fixed      xt1 = xt10;
    204         Fixed      xt2 = xt20;
    205 
    206         yt1 += YT1_INCR;
    207         yt2 += YT2_INCR;
    208 
    209 #define  XT1_INCR  FIXED_FROM_FLOAT(1/173.)
    210 #define  XT2_INCR  FIXED_FROM_FLOAT(1/242.)
    211 
    212 #if OPTIMIZE_WRITES
    213         /* optimize memory writes by generating one aligned 32-bit store
    214          * for every pair of pixels.
    215          */
    216         uint16_t*  line_end = line + info->width;
    217 
    218         if (line < line_end) {
    219             if (((uint32_t)line & 3) != 0) {
    220                 Fixed ii = base + fixed_sin(xt1) + fixed_sin(xt2);
    221 
    222                 xt1 += XT1_INCR;
    223                 xt2 += XT2_INCR;
    224 
    225                 line[0] = palette_from_fixed(ii >> 2);
    226                 line++;
    227             }
    228 
    229             while (line + 2 <= line_end) {
    230                 Fixed i1 = base + fixed_sin(xt1) + fixed_sin(xt2);
    231                 xt1 += XT1_INCR;
    232                 xt2 += XT2_INCR;
    233 
    234                 Fixed i2 = base + fixed_sin(xt1) + fixed_sin(xt2);
    235                 xt1 += XT1_INCR;
    236                 xt2 += XT2_INCR;
    237 
    238                 uint32_t  pixel = ((uint32_t)palette_from_fixed(i1 >> 2) << 16) |
    239                                    (uint32_t)palette_from_fixed(i2 >> 2);
    240 
    241                 ((uint32_t*)line)[0] = pixel;
    242                 line += 2;
    243             }
    244 
    245             if (line < line_end) {
    246                 Fixed ii = base + fixed_sin(xt1) + fixed_sin(xt2);
    247                 line[0] = palette_from_fixed(ii >> 2);
    248                 line++;
    249             }
    250         }
    251 #else /* !OPTIMIZE_WRITES */
    252         int xx;
    253         for (xx = 0; xx < info->width; xx++) {
    254 
    255             Fixed ii = base + fixed_sin(xt1) + fixed_sin(xt2);
    256 
    257             xt1 += XT1_INCR;
    258             xt2 += XT2_INCR;
    259 
    260             line[xx] = palette_from_fixed(ii / 4);
    261         }
    262 #endif /* !OPTIMIZE_WRITES */
    263 
    264         // go to next line
    265         pixels = (char*)pixels + info->stride;
    266     }
    267 }
    268 
    269 /* simple stats management */
    270 typedef struct {
    271     double  renderTime;
    272     double  frameTime;
    273 } FrameStats;
    274 
    275 #define  MAX_FRAME_STATS  200
    276 #define  MAX_PERIOD_MS    1500
    277 
    278 typedef struct {
    279     double  firstTime;
    280     double  lastTime;
    281     double  frameTime;
    282 
    283     int         firstFrame;
    284     int         numFrames;
    285     FrameStats  frames[ MAX_FRAME_STATS ];
    286 } Stats;
    287 
    288 static void
    289 stats_init( Stats*  s )
    290 {
    291     s->lastTime = now_ms();
    292     s->firstTime = 0.;
    293     s->firstFrame = 0;
    294     s->numFrames  = 0;
    295 }
    296 
    297 static void
    298 stats_startFrame( Stats*  s )
    299 {
    300     s->frameTime = now_ms();
    301 }
    302 
    303 static void
    304 stats_endFrame( Stats*  s )
    305 {
    306     double now = now_ms();
    307     double renderTime = now - s->frameTime;
    308     double frameTime  = now - s->lastTime;
    309     int nn;
    310 
    311     if (now - s->firstTime >= MAX_PERIOD_MS) {
    312         if (s->numFrames > 0) {
    313             double minRender, maxRender, avgRender;
    314             double minFrame, maxFrame, avgFrame;
    315             int count;
    316 
    317             nn = s->firstFrame;
    318             minRender = maxRender = avgRender = s->frames[nn].renderTime;
    319             minFrame  = maxFrame  = avgFrame  = s->frames[nn].frameTime;
    320             for (count = s->numFrames; count > 0; count-- ) {
    321                 nn += 1;
    322                 if (nn >= MAX_FRAME_STATS)
    323                     nn -= MAX_FRAME_STATS;
    324                 double render = s->frames[nn].renderTime;
    325                 if (render < minRender) minRender = render;
    326                 if (render > maxRender) maxRender = render;
    327                 double frame = s->frames[nn].frameTime;
    328                 if (frame < minFrame) minFrame = frame;
    329                 if (frame > maxFrame) maxFrame = frame;
    330                 avgRender += render;
    331                 avgFrame  += frame;
    332             }
    333             avgRender /= s->numFrames;
    334             avgFrame  /= s->numFrames;
    335 
    336             LOGI("frame/s (avg,min,max) = (%.1f,%.1f,%.1f) "
    337                  "render time ms (avg,min,max) = (%.1f,%.1f,%.1f)\n",
    338                  1000./avgFrame, 1000./maxFrame, 1000./minFrame,
    339                  avgRender, minRender, maxRender);
    340         }
    341         s->numFrames  = 0;
    342         s->firstFrame = 0;
    343         s->firstTime  = now;
    344     }
    345 
    346     nn = s->firstFrame + s->numFrames;
    347     if (nn >= MAX_FRAME_STATS)
    348         nn -= MAX_FRAME_STATS;
    349 
    350     s->frames[nn].renderTime = renderTime;
    351     s->frames[nn].frameTime  = frameTime;
    352 
    353     if (s->numFrames < MAX_FRAME_STATS) {
    354         s->numFrames += 1;
    355     } else {
    356         s->firstFrame += 1;
    357         if (s->firstFrame >= MAX_FRAME_STATS)
    358             s->firstFrame -= MAX_FRAME_STATS;
    359     }
    360 
    361     s->lastTime = now;
    362 }
    363 
    364 JNIEXPORT void JNICALL Java_com_example_plasma_PlasmaView_renderPlasma(JNIEnv * env, jobject  obj, jobject bitmap,  jlong  time_ms)
    365 {
    366     AndroidBitmapInfo  info;
    367     void*              pixels;
    368     int                ret;
    369     static Stats       stats;
    370     static int         init;
    371 
    372     if (!init) {
    373         init_tables();
    374         stats_init(&stats);
    375         init = 1;
    376     }
    377 
    378     if ((ret = AndroidBitmap_getInfo(env, bitmap, &info)) < 0) {
    379         LOGE("AndroidBitmap_getInfo() failed ! error=%d", ret);
    380         return;
    381     }
    382 
    383     if (info.format != ANDROID_BITMAP_FORMAT_RGB_565) {
    384         LOGE("Bitmap format is not RGB_565 !");
    385         return;
    386     }
    387 
    388     if ((ret = AndroidBitmap_lockPixels(env, bitmap, &pixels)) < 0) {
    389         LOGE("AndroidBitmap_lockPixels() failed ! error=%d", ret);
    390     }
    391 
    392     stats_startFrame(&stats);
    393 
    394     /* Now fill the values with a nice little plasma */
    395     fill_plasma(&info, pixels, time_ms );
    396 
    397     AndroidBitmap_unlockPixels(env, bitmap);
    398 
    399     stats_endFrame(&stats);
    400 }
    401