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      1 #include "rs_core.rsh"
      2 #include "rs_structs.h"
      3 
      4 
      5 // 565 Conversion bits taken from SkBitmap
      6 #define SK_R16_BITS     5
      7 #define SK_G16_BITS     6
      8 #define SK_B16_BITS     5
      9 
     10 #define SK_R16_SHIFT    (SK_B16_BITS + SK_G16_BITS)
     11 #define SK_G16_SHIFT    (SK_B16_BITS)
     12 #define SK_B16_SHIFT    0
     13 
     14 #define SK_R16_MASK     ((1 << SK_R16_BITS) - 1)
     15 #define SK_G16_MASK     ((1 << SK_G16_BITS) - 1)
     16 #define SK_B16_MASK     ((1 << SK_B16_BITS) - 1)
     17 
     18 #define SkGetPackedR16(color)   (((unsigned)(color) >> SK_R16_SHIFT) & SK_R16_MASK)
     19 #define SkGetPackedG16(color)   (((unsigned)(color) >> SK_G16_SHIFT) & SK_G16_MASK)
     20 #define SkGetPackedB16(color)   (((unsigned)(color) >> SK_B16_SHIFT) & SK_B16_MASK)
     21 
     22 static inline unsigned SkR16ToR32(unsigned r) {
     23     return (r << (8 - SK_R16_BITS)) | (r >> (2 * SK_R16_BITS - 8));
     24 }
     25 
     26 static inline unsigned SkG16ToG32(unsigned g) {
     27     return (g << (8 - SK_G16_BITS)) | (g >> (2 * SK_G16_BITS - 8));
     28 }
     29 
     30 static inline unsigned SkB16ToB32(unsigned b) {
     31     return (b << (8 - SK_B16_BITS)) | (b >> (2 * SK_B16_BITS - 8));
     32 }
     33 
     34 #define SkPacked16ToR32(c)      SkR16ToR32(SkGetPackedR16(c))
     35 #define SkPacked16ToG32(c)      SkG16ToG32(SkGetPackedG16(c))
     36 #define SkPacked16ToB32(c)      SkB16ToB32(SkGetPackedB16(c))
     37 
     38 static float3 getFrom565(uint16_t color) {
     39     float3 result;
     40     result.x = (float)SkPacked16ToR32(color);
     41     result.y = (float)SkPacked16ToG32(color);
     42     result.z = (float)SkPacked16ToB32(color);
     43     return result;
     44 }
     45 
     46 /**
     47 * Allocation sampling
     48 */
     49 static inline float __attribute__((overloadable))
     50         getElementAt1(const uint8_t *p, int32_t x) {
     51     float r = p[x];
     52     return r;
     53 }
     54 
     55 static inline float2 __attribute__((overloadable))
     56         getElementAt2(const uint8_t *p, int32_t x) {
     57     x *= 2;
     58     float2 r = {p[x], p[x+1]};
     59     return r;
     60 }
     61 
     62 static inline float3 __attribute__((overloadable))
     63         getElementAt3(const uint8_t *p, int32_t x) {
     64     x *= 4;
     65     float3 r = {p[x], p[x+1], p[x+2]};
     66     return r;
     67 }
     68 
     69 static inline float4 __attribute__((overloadable))
     70         getElementAt4(const uint8_t *p, int32_t x) {
     71     x *= 4;
     72     const uchar4 *p2 = (const uchar4 *)&p[x];
     73     return convert_float4(p2[0]);
     74 }
     75 
     76 static inline float3 __attribute__((overloadable))
     77         getElementAt565(const uint8_t *p, int32_t x) {
     78     x *= 2;
     79     float3 r = getFrom565(((const uint16_t *)p)[0]);
     80     return r;
     81 }
     82 
     83 static inline float __attribute__((overloadable))
     84         getElementAt1(const uint8_t *p, size_t stride, int32_t x, int32_t y) {
     85     p += y * stride;
     86     float r = p[x];
     87     return r;
     88 }
     89 
     90 static inline float2 __attribute__((overloadable))
     91         getElementAt2(const uint8_t *p, size_t stride, int32_t x, int32_t y) {
     92     p += y * stride;
     93     x *= 2;
     94     float2 r = {p[x], p[x+1]};
     95     return r;
     96 }
     97 
     98 static inline float3 __attribute__((overloadable))
     99         getElementAt3(const uint8_t *p, size_t stride, int32_t x, int32_t y) {
    100     p += y * stride;
    101     x *= 4;
    102     float3 r = {p[x], p[x+1], p[x+2]};
    103     return r;
    104 }
    105 
    106 static inline float4 __attribute__((overloadable))
    107         getElementAt4(const uint8_t *p, size_t stride, int32_t x, int32_t y) {
    108     p += y * stride;
    109     x *= 4;
    110     float4 r = {p[x], p[x+1], p[x+2], p[x+3]};
    111     return r;
    112 }
    113 
    114 static inline float3 __attribute__((overloadable))
    115         getElementAt565(const uint8_t *p, size_t stride, int32_t x, int32_t y) {
    116     p += y * stride;
    117     x *= 2;
    118     float3 r = getFrom565(((const uint16_t *)p)[0]);
    119     return r;
    120 }
    121 
    122 
    123 
    124 
    125 
    126 static float4 __attribute__((overloadable))
    127             getSample_A(const uint8_t *p, int32_t iPixel,
    128                           int32_t next, float w0, float w1) {
    129     float p0 = getElementAt1(p, iPixel);
    130     float p1 = getElementAt1(p, next);
    131     float r = p0 * w0 + p1 * w1;
    132     r *= (1.f / 255.f);
    133     float4 ret = {0.f, 0.f, 0.f, r};
    134     return ret;
    135 }
    136 static float4 __attribute__((overloadable))
    137             getSample_L(const uint8_t *p, int32_t iPixel,
    138                           int32_t next, float w0, float w1) {
    139     float p0 = getElementAt1(p, iPixel);
    140     float p1 = getElementAt1(p, next);
    141     float r = p0 * w0 + p1 * w1;
    142     r *= (1.f / 255.f);
    143     float4 ret = {r, r, r, 1.f};
    144     return ret;
    145 }
    146 static float4 __attribute__((overloadable))
    147             getSample_LA(const uint8_t *p, int32_t iPixel,
    148                            int32_t next, float w0, float w1) {
    149     float2 p0 = getElementAt2(p, iPixel);
    150     float2 p1 = getElementAt2(p, next);
    151     float2 r = p0 * w0 + p1 * w1;
    152     r *= (1.f / 255.f);
    153     float4 ret = {r.x, r.x, r.x, r.y};
    154     return ret;
    155 }
    156 static float4 __attribute__((overloadable))
    157             getSample_RGB(const uint8_t *p, int32_t iPixel,
    158                             int32_t next, float w0, float w1) {
    159     float3 p0 = getElementAt3(p, iPixel);
    160     float3 p1 = getElementAt3(p, next);
    161     float3 r = p0 * w0 + p1 * w1;
    162     r *= (1.f / 255.f);
    163     float4 ret = {r.x, r.x, r.z, 1.f};
    164     return ret;
    165 }
    166 static float4 __attribute__((overloadable))
    167             getSample_565(const uint8_t *p, int32_t iPixel,
    168                            int32_t next, float w0, float w1) {
    169     float3 p0 = getElementAt565(p, iPixel);
    170     float3 p1 = getElementAt565(p, next);
    171     float3 r = p0 * w0 + p1 * w1;
    172     r *= (1.f / 255.f);
    173     float4 ret = {r.x, r.x, r.z, 1.f};
    174     return ret;
    175 }
    176 static float4 __attribute__((overloadable))
    177             getSample_RGBA(const uint8_t *p, int32_t iPixel,
    178                              int32_t next, float w0, float w1) {
    179     float4 p0 = getElementAt4(p, iPixel);
    180     float4 p1 = getElementAt4(p, next);
    181     float4 r = p0 * w0 + p1 * w1;
    182     r *= (1.f / 255.f);
    183     return r;
    184 }
    185 
    186 
    187 static float4 __attribute__((overloadable))
    188             getSample_A(const uint8_t *p, size_t stride,
    189                           int locX, int locY, int nextX, int nextY,
    190                           float w0, float w1, float w2, float w3) {
    191     float p0 = getElementAt1(p, stride, locX, locY);
    192     float p1 = getElementAt1(p, stride, nextX, locY);
    193     float p2 = getElementAt1(p, stride, locX, nextY);
    194     float p3 = getElementAt1(p, stride, nextX, nextY);
    195     float r = p0 * w0 + p1 * w1 + p2 * w2 + p3 * w3;
    196     r *= (1.f / 255.f);
    197     float4 ret = {0.f, 0.f, 0.f, r};
    198     return ret;
    199 }
    200 static float4 __attribute__((overloadable))
    201             getSample_L(const uint8_t *p, size_t stride,
    202                          int locX, int locY, int nextX, int nextY,
    203                          float w0, float w1, float w2, float w3) {
    204     float p0 = getElementAt1(p, stride, locX, locY);
    205     float p1 = getElementAt1(p, stride, nextX, locY);
    206     float p2 = getElementAt1(p, stride, locX, nextY);
    207     float p3 = getElementAt1(p, stride, nextX, nextY);
    208     float r = p0 * w0 + p1 * w1 + p2 * w2 + p3 * w3;
    209     r *= (1.f / 255.f);
    210     float4 ret = {r, r, r, 1.f};
    211     return ret;
    212 }
    213 static float4 __attribute__((overloadable))
    214             getSample_LA(const uint8_t *p, size_t stride,
    215                          int locX, int locY, int nextX, int nextY,
    216                          float w0, float w1, float w2, float w3) {
    217     float2 p0 = getElementAt2(p, stride, locX, locY);
    218     float2 p1 = getElementAt2(p, stride, nextX, locY);
    219     float2 p2 = getElementAt2(p, stride, locX, nextY);
    220     float2 p3 = getElementAt2(p, stride, nextX, nextY);
    221     float2 r = p0 * w0 + p1 * w1 + p2 * w2 + p3 * w3;
    222     r *= (1.f / 255.f);
    223     float4 ret = {r.x, r.x, r.x, r.y};
    224     return ret;
    225 }
    226 static float4 __attribute__((overloadable))
    227             getSample_RGB(const uint8_t *p, size_t stride,
    228                          int locX, int locY, int nextX, int nextY,
    229                          float w0, float w1, float w2, float w3) {
    230     float4 p0 = getElementAt4(p, stride, locX, locY);
    231     float4 p1 = getElementAt4(p, stride, nextX, locY);
    232     float4 p2 = getElementAt4(p, stride, locX, nextY);
    233     float4 p3 = getElementAt4(p, stride, nextX, nextY);
    234     float4 r = p0 * w0 + p1 * w1 + p2 * w2 + p3 * w3;
    235     r *= (1.f / 255.f);
    236     float4 ret = {r.x, r.y, r.z, 1.f};
    237     return ret;
    238 }
    239 static float4 __attribute__((overloadable))
    240             getSample_RGBA(const uint8_t *p, size_t stride,
    241                          int locX, int locY, int nextX, int nextY,
    242                          float w0, float w1, float w2, float w3) {
    243     float4 p0 = getElementAt4(p, stride, locX, locY);
    244     float4 p1 = getElementAt4(p, stride, nextX, locY);
    245     float4 p2 = getElementAt4(p, stride, locX, nextY);
    246     float4 p3 = getElementAt4(p, stride, nextX, nextY);
    247     float4 r = p0 * w0 + p1 * w1 + p2 * w2 + p3 * w3;
    248     r *= (1.f / 255.f);
    249     return r;
    250 }
    251 static float4 __attribute__((overloadable))
    252             getSample_565(const uint8_t *p, size_t stride,
    253                          int locX, int locY, int nextX, int nextY,
    254                          float w0, float w1, float w2, float w3) {
    255     float3 p0 = getElementAt565(p, stride, locX, locY);
    256     float3 p1 = getElementAt565(p, stride, nextX, locY);
    257     float3 p2 = getElementAt565(p, stride, locX, nextY);
    258     float3 p3 = getElementAt565(p, stride, nextX, nextY);
    259     float3 r = p0 * w0 + p1 * w1 + p2 * w2 + p3 * w3;
    260     r *= (1.f / 255.f);
    261     float4 ret;
    262     ret.rgb = r;
    263     ret.w = 1.f;
    264     return ret;
    265 }
    266 
    267 static float4 __attribute__((overloadable))
    268         getBilinearSample1D(const Allocation_t *alloc, float2 weights,
    269                           uint32_t iPixel, uint32_t next,
    270                           rs_data_kind dk, rs_data_type dt, uint32_t lod) {
    271 
    272      const uint8_t *p = (const uint8_t *)alloc->mHal.drvState.lod[lod].mallocPtr;
    273 
    274      switch(dk) {
    275      case RS_KIND_PIXEL_RGBA:
    276          return getSample_RGBA(p, iPixel, next, weights.x, weights.y);
    277      case RS_KIND_PIXEL_A:
    278          return getSample_A(p, iPixel, next, weights.x, weights.y);
    279      case RS_KIND_PIXEL_RGB:
    280          if (dt == RS_TYPE_UNSIGNED_5_6_5) {
    281              return getSample_565(p, iPixel, next, weights.x, weights.y);
    282          }
    283          return getSample_RGB(p, iPixel, next, weights.x, weights.y);
    284      case RS_KIND_PIXEL_L:
    285          return getSample_L(p, iPixel, next, weights.x, weights.y);
    286      case RS_KIND_PIXEL_LA:
    287          return getSample_LA(p, iPixel, next, weights.x, weights.y);
    288 
    289      default:
    290          //__builtin_unreachable();
    291          break;
    292      }
    293 
    294      //__builtin_unreachable();
    295      return 0.f;
    296 }
    297 
    298 static uint32_t wrapI(rs_sampler_value wrap, int32_t coord, int32_t size) {
    299     if (wrap == RS_SAMPLER_WRAP) {
    300         coord = coord % size;
    301         if (coord < 0) {
    302             coord += size;
    303         }
    304     }
    305     if (wrap == RS_SAMPLER_MIRRORED_REPEAT) {
    306         coord = coord % (size * 2);
    307         if (coord < 0) {
    308             coord = (size * 2) + coord;
    309         }
    310         if (coord >= size) {
    311             coord = (size * 2 - 1) - coord;
    312         }
    313     }
    314     return (uint32_t)max(0, min(coord, size - 1));
    315 }
    316 
    317 static float4 __attribute__((overloadable))
    318         getBilinearSample2D(const Allocation_t *alloc, float w0, float w1, float w2, float w3,
    319                           int lx, int ly, int nx, int ny,
    320                           rs_data_kind dk, rs_data_type dt, uint32_t lod) {
    321 
    322     const uint8_t *p = (const uint8_t *)alloc->mHal.drvState.lod[lod].mallocPtr;
    323     size_t stride = alloc->mHal.drvState.lod[lod].stride;
    324 
    325     switch(dk) {
    326     case RS_KIND_PIXEL_RGBA:
    327         return getSample_RGBA(p, stride, lx, ly, nx, ny, w0, w1, w2, w3);
    328     case RS_KIND_PIXEL_A:
    329         return getSample_A(p, stride, lx, ly, nx, ny, w0, w1, w2, w3);
    330     case RS_KIND_PIXEL_LA:
    331         return getSample_LA(p, stride, lx, ly, nx, ny, w0, w1, w2, w3);
    332     case RS_KIND_PIXEL_RGB:
    333         if (dt == RS_TYPE_UNSIGNED_5_6_5) {
    334             return getSample_565(p, stride, lx, ly, nx, ny, w0, w1, w2, w3);
    335         }
    336         return getSample_RGB(p, stride, lx, ly, nx, ny, w0, w1, w2, w3);
    337     case RS_KIND_PIXEL_L:
    338         return getSample_L(p, stride, lx, ly, nx, ny, w0, w1, w2, w3);
    339 
    340     default:
    341         break;
    342     }
    343 
    344     return 0.f;
    345 }
    346 
    347 static float4  __attribute__((overloadable))
    348         getNearestSample(const Allocation_t *alloc, uint32_t iPixel, rs_data_kind dk,
    349                          rs_data_type dt, uint32_t lod) {
    350 
    351     const uint8_t *p = (const uint8_t *)alloc->mHal.drvState.lod[lod].mallocPtr;
    352 
    353     float4 result = {0.f, 0.f, 0.f, 255.f};
    354 
    355     switch(dk) {
    356     case RS_KIND_PIXEL_RGBA:
    357         result = getElementAt4(p, iPixel);
    358         break;
    359     case RS_KIND_PIXEL_A:
    360         result.w = getElementAt1(p, iPixel);
    361         break;
    362     case RS_KIND_PIXEL_LA:
    363         result.zw = getElementAt2(p, iPixel);
    364         result.xy = result.z;
    365         break;
    366     case RS_KIND_PIXEL_RGB:
    367         if (dt == RS_TYPE_UNSIGNED_5_6_5) {
    368             result.xyz = getElementAt565(p, iPixel);
    369         } else {
    370             result.xyz = getElementAt3(p, iPixel);
    371         }
    372         break;
    373     case RS_KIND_PIXEL_L:
    374         result.xyz = getElementAt1(p, iPixel);
    375 
    376     default:
    377         //__builtin_unreachable();
    378         break;
    379     }
    380 
    381     return result * 0.003921569f;
    382 }
    383 
    384 static float4  __attribute__((overloadable))
    385         getNearestSample(const Allocation_t *alloc, uint2 iPixel, rs_data_kind dk,
    386                          rs_data_type dt, uint32_t lod) {
    387 
    388     const uint8_t *p = (const uint8_t *)alloc->mHal.drvState.lod[lod].mallocPtr;
    389     size_t stride = alloc->mHal.drvState.lod[lod].stride;
    390 
    391     float4 result = {0.f, 0.f, 0.f, 255.f};
    392 
    393     switch(dk) {
    394     case RS_KIND_PIXEL_RGBA:
    395         result = getElementAt4(p, stride, iPixel.x, iPixel.y);
    396         break;
    397     case RS_KIND_PIXEL_A:
    398         result.w = getElementAt1(p, stride, iPixel.x, iPixel.y);
    399         break;
    400     case RS_KIND_PIXEL_LA:
    401         result.zw = getElementAt2(p, stride, iPixel.x, iPixel.y);
    402         result.xy = result.z;
    403         break;
    404     case RS_KIND_PIXEL_RGB:
    405         if (dt == RS_TYPE_UNSIGNED_5_6_5) {
    406             result.xyz = getElementAt565(p, stride, iPixel.x, iPixel.y);
    407         } else {
    408             result.xyz = getElementAt3(p, stride, iPixel.x, iPixel.y);
    409         }
    410         break;
    411 
    412     default:
    413         //__builtin_unreachable();
    414         break;
    415     }
    416 
    417     return result * 0.003921569f;
    418 }
    419 
    420 static float4 __attribute__((overloadable))
    421         sample_LOD_LinearPixel(const Allocation_t *alloc,
    422                                rs_data_kind dk, rs_data_type dt,
    423                                rs_sampler_value wrapS,
    424                                float uv, uint32_t lod) {
    425 
    426     int32_t sourceW = alloc->mHal.drvState.lod[lod].dimX;
    427     float pixelUV = uv * (float)(sourceW);
    428     int32_t iPixel = floor(pixelUV);
    429     float frac = pixelUV - (float)iPixel;
    430 
    431     if (frac < 0.5f) {
    432         iPixel -= 1;
    433         frac += 0.5f;
    434     } else {
    435         frac -= 0.5f;
    436     }
    437 
    438     float oneMinusFrac = 1.0f - frac;
    439 
    440     float2 weights;
    441     weights.x = oneMinusFrac;
    442     weights.y = frac;
    443 
    444     uint32_t next = wrapI(wrapS, iPixel + 1, sourceW);
    445     uint32_t location = wrapI(wrapS, iPixel, sourceW);
    446 
    447     return getBilinearSample1D(alloc, weights, location, next, dk, dt, lod);
    448 }
    449 
    450 static float4 __attribute__((overloadable))
    451         sample_LOD_NearestPixel(const Allocation_t *alloc,
    452                                 rs_data_kind dk, rs_data_type dt,
    453                                 rs_sampler_value wrapS,
    454                                 float uv, uint32_t lod) {
    455 
    456     int32_t sourceW = alloc->mHal.drvState.lod[lod].dimX;
    457     int32_t iPixel = floor(uv * (float)(sourceW));
    458     uint32_t location = wrapI(wrapS, iPixel, sourceW);
    459 
    460     return getNearestSample(alloc, location, dk, dt, lod);
    461 }
    462 
    463 static float4 __attribute__((overloadable))
    464         sample_LOD_LinearPixel(const Allocation_t *alloc,
    465                                rs_data_kind dk, rs_data_type dt,
    466                                rs_sampler_value wrapS,
    467                                rs_sampler_value wrapT,
    468                                float2 uv, uint32_t lod) {
    469 
    470     int sourceW = alloc->mHal.drvState.lod[lod].dimX;
    471     int sourceH = alloc->mHal.drvState.lod[lod].dimY;
    472 
    473     float pixelU = uv.x * sourceW;
    474     float pixelV = uv.y * sourceH;
    475     int iPixelU = floor(pixelU);
    476     int iPixelV = floor(pixelV);
    477     float fracU = pixelU - iPixelU;
    478     float fracV = pixelV - iPixelV;
    479 
    480     if (fracU < 0.5f) {
    481         iPixelU -= 1;
    482         fracU += 0.5f;
    483     } else {
    484         fracU -= 0.5f;
    485     }
    486     if (fracV < 0.5f) {
    487         iPixelV -= 1;
    488         fracV += 0.5f;
    489     } else {
    490         fracV -= 0.5f;
    491     }
    492     float oneMinusFracU = 1.0f - fracU;
    493     float oneMinusFracV = 1.0f - fracV;
    494 
    495     float w0 = oneMinusFracU * oneMinusFracV;
    496     float w1 = fracU * oneMinusFracV;
    497     float w2 = oneMinusFracU * fracV;
    498     float w3 = fracU * fracV;
    499 
    500     int nx = wrapI(wrapS, iPixelU + 1, sourceW);
    501     int ny = wrapI(wrapT, iPixelV + 1, sourceH);
    502     int lx = wrapI(wrapS, iPixelU, sourceW);
    503     int ly = wrapI(wrapT, iPixelV, sourceH);
    504 
    505     return getBilinearSample2D(alloc, w0, w1, w2, w3, lx, ly, nx, ny, dk, dt, lod);
    506 
    507 }
    508 
    509 static float4 __attribute__((overloadable))
    510         sample_LOD_NearestPixel(const Allocation_t *alloc,
    511                                 rs_data_kind dk, rs_data_type dt,
    512                                 rs_sampler_value wrapS,
    513                                 rs_sampler_value wrapT,
    514                                 float2 uv, uint32_t lod) {
    515     int sourceW = alloc->mHal.drvState.lod[lod].dimX;
    516     int sourceH = alloc->mHal.drvState.lod[lod].dimY;
    517 
    518     float2 dimF;
    519     dimF.x = (float)(sourceW);
    520     dimF.y = (float)(sourceH);
    521     int2 iPixel = convert_int2(floor(uv * dimF));
    522 
    523     uint2 location;
    524     location.x = wrapI(wrapS, iPixel.x, sourceW);
    525     location.y = wrapI(wrapT, iPixel.y, sourceH);
    526     return getNearestSample(alloc, location, dk, dt, lod);
    527 }
    528 
    529 extern float4 __attribute__((overloadable))
    530         rsSample(rs_allocation a, rs_sampler s, float uv, float lod) {
    531 
    532     const Allocation_t *alloc = (const Allocation_t *)a.p;
    533     const Sampler_t *prog = (Sampler_t *)s.p;
    534     const Type_t *type = (Type_t *)alloc->mHal.state.type;
    535     const Element_t *elem = type->mHal.state.element;
    536     rs_data_kind dk = elem->mHal.state.dataKind;
    537     rs_data_type dt = elem->mHal.state.dataType;
    538     rs_sampler_value sampleMin = prog->mHal.state.minFilter;
    539     rs_sampler_value sampleMag = prog->mHal.state.magFilter;
    540     rs_sampler_value wrapS = prog->mHal.state.wrapS;
    541 
    542     if (!(alloc->mHal.state.usageFlags & RS_ALLOCATION_USAGE_GRAPHICS_TEXTURE)) {
    543         return 0.f;
    544     }
    545 
    546     if (lod <= 0.0f) {
    547         if (sampleMag == RS_SAMPLER_NEAREST) {
    548             return sample_LOD_NearestPixel(alloc, dk, dt, wrapS, uv, 0);
    549         }
    550         return sample_LOD_LinearPixel(alloc, dk, dt, wrapS, uv, 0);
    551     }
    552 
    553     if (sampleMin == RS_SAMPLER_LINEAR_MIP_NEAREST) {
    554         uint32_t maxLOD = type->mHal.state.lodCount - 1;
    555         lod = min(lod, (float)maxLOD);
    556         uint32_t nearestLOD = (uint32_t)round(lod);
    557         return sample_LOD_LinearPixel(alloc, dk, dt, wrapS, uv, nearestLOD);
    558     }
    559 
    560     if (sampleMin == RS_SAMPLER_LINEAR_MIP_LINEAR) {
    561         uint32_t lod0 = (uint32_t)floor(lod);
    562         uint32_t lod1 = (uint32_t)ceil(lod);
    563         uint32_t maxLOD = type->mHal.state.lodCount - 1;
    564         lod0 = min(lod0, maxLOD);
    565         lod1 = min(lod1, maxLOD);
    566         float4 sample0 = sample_LOD_LinearPixel(alloc, dk, dt, wrapS, uv, lod0);
    567         float4 sample1 = sample_LOD_LinearPixel(alloc, dk, dt, wrapS, uv, lod1);
    568         float frac = lod - (float)lod0;
    569         return sample0 * (1.0f - frac) + sample1 * frac;
    570     }
    571 
    572     return sample_LOD_NearestPixel(alloc, dk, dt, wrapS, uv, 0);
    573 }
    574 
    575 extern float4 __attribute__((overloadable))
    576         rsSample(rs_allocation a, rs_sampler s, float location) {
    577     return rsSample(a, s, location, 0);
    578 }
    579 
    580 
    581 extern float4 __attribute__((overloadable))
    582         rsSample(rs_allocation a, rs_sampler s, float2 uv, float lod) {
    583 
    584     const Allocation_t *alloc = (const Allocation_t *)a.p;
    585     const Sampler_t *prog = (Sampler_t *)s.p;
    586     const Type_t *type = (Type_t *)alloc->mHal.state.type;
    587     const Element_t *elem = type->mHal.state.element;
    588     rs_data_kind dk = elem->mHal.state.dataKind;
    589     rs_data_type dt = elem->mHal.state.dataType;
    590     rs_sampler_value sampleMin = prog->mHal.state.minFilter;
    591     rs_sampler_value sampleMag = prog->mHal.state.magFilter;
    592     rs_sampler_value wrapS = prog->mHal.state.wrapS;
    593     rs_sampler_value wrapT = prog->mHal.state.wrapT;
    594 
    595     if (!(alloc->mHal.state.usageFlags & RS_ALLOCATION_USAGE_GRAPHICS_TEXTURE)) {
    596         return 0.f;
    597     }
    598 
    599     if (lod <= 0.0f) {
    600         if (sampleMag == RS_SAMPLER_NEAREST) {
    601             return sample_LOD_NearestPixel(alloc, dk, dt, wrapS, wrapT, uv, 0);
    602         }
    603         return sample_LOD_LinearPixel(alloc, dk, dt, wrapS, wrapT, uv, 0);
    604     }
    605 
    606     if (sampleMin == RS_SAMPLER_LINEAR_MIP_NEAREST) {
    607         uint32_t maxLOD = type->mHal.state.lodCount - 1;
    608         lod = min(lod, (float)maxLOD);
    609         uint32_t nearestLOD = (uint32_t)round(lod);
    610         return sample_LOD_LinearPixel(alloc, dk, dt, wrapS, wrapT, uv, nearestLOD);
    611     }
    612 
    613     if (sampleMin == RS_SAMPLER_LINEAR_MIP_LINEAR) {
    614         uint32_t lod0 = (uint32_t)floor(lod);
    615         uint32_t lod1 = (uint32_t)ceil(lod);
    616         uint32_t maxLOD = type->mHal.state.lodCount - 1;
    617         lod0 = min(lod0, maxLOD);
    618         lod1 = min(lod1, maxLOD);
    619         float4 sample0 = sample_LOD_LinearPixel(alloc, dk, dt, wrapS, wrapT, uv, lod0);
    620         float4 sample1 = sample_LOD_LinearPixel(alloc, dk, dt, wrapS, wrapT, uv, lod1);
    621         float frac = lod - (float)lod0;
    622         return sample0 * (1.0f - frac) + sample1 * frac;
    623     }
    624 
    625     return sample_LOD_NearestPixel(alloc, dk, dt, wrapS, wrapT, uv, 0);
    626 }
    627 
    628 extern float4 __attribute__((overloadable))
    629         rsSample(rs_allocation a, rs_sampler s, float2 uv) {
    630 
    631     const Allocation_t *alloc = (const Allocation_t *)a.p;
    632     const Sampler_t *prog = (Sampler_t *)s.p;
    633     const Type_t *type = (Type_t *)alloc->mHal.state.type;
    634     const Element_t *elem = type->mHal.state.element;
    635     rs_data_kind dk = elem->mHal.state.dataKind;
    636     rs_data_type dt = elem->mHal.state.dataType;
    637     rs_sampler_value wrapS = prog->mHal.state.wrapS;
    638     rs_sampler_value wrapT = prog->mHal.state.wrapT;
    639 
    640     if (!(alloc->mHal.state.usageFlags & RS_ALLOCATION_USAGE_GRAPHICS_TEXTURE)) {
    641         return 0.f;
    642     }
    643 
    644     if (prog->mHal.state.magFilter == RS_SAMPLER_NEAREST) {
    645         return sample_LOD_NearestPixel(alloc, dk, dt, wrapS, wrapT, uv, 0);
    646     }
    647     return sample_LOD_LinearPixel(alloc, dk, dt, wrapS, wrapT, uv, 0);
    648 }
    649