的renderScript：不匹配功能rsGetElementAt_uchar4

Question

我已經寫的很短的RS，但gradle這個同步的Android工作室給我之後錯誤

Error:(8, 34) error: no matching function for call to 'rsGetElementAt_uchar4'

腳本：

#pragma version(1) 
#pragma rs java_package_name(xx.xxx.xxxxxxx) 

uchar4 road = 0; 
const uchar4 nothing = 0; 

void init() { 
    road.a = 0xff; 
} 

uchar4 __attribute__((kernel)) kernel(uchar4 original, uint32_t x, uint32_t y) { 
    uchar4 masked = rsGetElementAt_uchar4(extra_alloc, x, y)); 
    if (original.r != masked.r || original.g != masked.g || original.b != masked.b) { 
     return road; 
    } else { 
     return nothing; 
    } 
} 

在的build.gradle：

defaultConfig { 
    applicationId "xx.xxx.xxxxxxx" 
    minSdkVersion 21 
    targetSdkVersion 26 
    versionCode 1 
    versionName "1.0" 
    renderscriptTargetApi 24 // I've tried almost every possible value 
    renderscriptSupportModeEnabled true 
} 

相同的代碼，但使用API​​ 23的作品：

#pragma version(1) 
#pragma rs java_package_name(gl.kid.maptilt) 

uchar4 road = 0; // I don't know, how to declare uchar4, any advice? 
const uchar4 nothing = 0; 

void init() { 
    road.a = 0xff; 
} 

uchar4 __attribute__((kernel)) root(uchar4 original, uchar4 masked, uint32_t x, uint32_t y) { 
    if (original.r != masked.r || original.g != masked.g || original.b != masked.b) { 
     return road; 
    } else { 
     return nothing; 
    } 
} 

Answer 1

我將從一份聲明開始，對RenderScript不太瞭解。這麼說，我想你跟着類似this question代碼，但你缺少行：

rs_allocation extra_alloc; 

注意在Java中，位在那裏設置：

script.set_extra_alloc(inAllocationExtra);