1 /* 2 * Copyright (C) 2013 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 "ip.rsh" 18 19 rs_allocation gSrc; 20 rs_allocation gDest; 21 rs_allocation gSums; 22 rs_allocation gSum; 23 24 int gWidth; 25 int gHeight; 26 int gStep; 27 int gSteps; 28 29 void RS_KERNEL pass1(uint x) { 30 for (int i=0; i < (256); i++) { 31 rsSetElementAt_int(gSums, 0, i, x); 32 } 33 34 for (int i = 0; i < gStep; i++) { 35 int py = x * gStep + i; 36 if (py >= gHeight) return; 37 38 for (int px=0; px < gWidth; px++) { 39 uchar4 c = rsGetElementAt_uchar4(gSrc, px, py); 40 int lum = (77 * c.r + 150 * c.g + 29 * c.b) >> 8; 41 42 int old = rsGetElementAt_int(gSums, lum, x); 43 rsSetElementAt_int(gSums, old+1, lum, x); 44 } 45 } 46 } 47 48 int RS_KERNEL pass2(uint x) { 49 int sum = 0; 50 for (int i=0; i < gSteps; i++) { 51 sum += rsGetElementAt_int(gSums, x, i); 52 } 53 return sum; 54 } 55 56 void rescale() { 57 int maxv = 0; 58 59 for (int i=0; i < 256; i++) { 60 maxv = max(maxv, rsGetElementAt_int(gSum, i)); 61 } 62 float overMax = (1.f / maxv) * gHeight; 63 64 for (int i=0; i < 256; i++) { 65 int t = rsGetElementAt_int(gSum, i); 66 t = gHeight - (overMax * rsGetElementAt_int(gSum, i)); 67 t = max(0, t); 68 rsSetElementAt_int(gSum, t, i); 69 } 70 } 71 72 static const uchar4 gClear = {0, 0, 0, 0xff}; 73 74 uchar4 RS_KERNEL clear() { 75 return gClear; 76 } 77 78 uchar4 RS_KERNEL draw(uint x, uint y) { 79 int l = rsGetElementAt_int(gSum, x >> 2); 80 if (y > l) { 81 return 0xff; 82 } 83 return gClear; 84 } 85
