Home | History | Annotate | Download | only in ui
      1 /*
      2  * Copyright (C) 2009 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 <system/graphics.h>
     18 #include <ui/Rect.h>
     19 
     20 namespace android {
     21 
     22 const Rect Rect::INVALID_RECT{0, 0, -1, -1};
     23 const Rect Rect::EMPTY_RECT{0, 0, 0, 0};
     24 
     25 static inline int32_t min(int32_t a, int32_t b) {
     26     return (a < b) ? a : b;
     27 }
     28 
     29 static inline int32_t max(int32_t a, int32_t b) {
     30     return (a > b) ? a : b;
     31 }
     32 
     33 void Rect::makeInvalid() {
     34     left = 0;
     35     top = 0;
     36     right = -1;
     37     bottom = -1;
     38 }
     39 
     40 bool Rect::operator <(const Rect& rhs) const {
     41     if (top < rhs.top) {
     42         return true;
     43     } else if (top == rhs.top) {
     44         if (left < rhs.left) {
     45             return true;
     46         } else if (left == rhs.left) {
     47             if (bottom < rhs.bottom) {
     48                 return true;
     49             } else if (bottom == rhs.bottom) {
     50                 if (right < rhs.right) {
     51                     return true;
     52                 }
     53             }
     54         }
     55     }
     56     return false;
     57 }
     58 
     59 Rect& Rect::offsetTo(int32_t x, int32_t y) {
     60     right -= left - x;
     61     bottom -= top - y;
     62     left = x;
     63     top = y;
     64     return *this;
     65 }
     66 
     67 Rect& Rect::offsetBy(int32_t x, int32_t y) {
     68     left += x;
     69     top += y;
     70     right += x;
     71     bottom += y;
     72     return *this;
     73 }
     74 
     75 const Rect Rect::operator +(const Point& rhs) const {
     76     const Rect result(left + rhs.x, top + rhs.y, right + rhs.x, bottom + rhs.y);
     77     return result;
     78 }
     79 
     80 const Rect Rect::operator -(const Point& rhs) const {
     81     const Rect result(left - rhs.x, top - rhs.y, right - rhs.x, bottom - rhs.y);
     82     return result;
     83 }
     84 
     85 bool Rect::intersect(const Rect& with, Rect* result) const {
     86     result->left = max(left, with.left);
     87     result->top = max(top, with.top);
     88     result->right = min(right, with.right);
     89     result->bottom = min(bottom, with.bottom);
     90     return !(result->isEmpty());
     91 }
     92 
     93 Rect Rect::transform(uint32_t xform, int32_t width, int32_t height) const {
     94     Rect result(*this);
     95     if (xform & HAL_TRANSFORM_FLIP_H) {
     96         result = Rect(width - result.right, result.top, width - result.left,
     97                 result.bottom);
     98     }
     99     if (xform & HAL_TRANSFORM_FLIP_V) {
    100         result = Rect(result.left, height - result.bottom, result.right,
    101                 height - result.top);
    102     }
    103     if (xform & HAL_TRANSFORM_ROT_90) {
    104         int left = height - result.bottom;
    105         int top = result.left;
    106         int right = height - result.top;
    107         int bottom = result.right;
    108         result = Rect(left, top, right, bottom);
    109     }
    110     return result;
    111 }
    112 
    113 Rect Rect::reduce(const Rect& exclude) const {
    114     Rect result(Rect::EMPTY_RECT);
    115 
    116     uint32_t mask = 0;
    117     mask |= (exclude.left   > left)   ? 1 : 0;
    118     mask |= (exclude.top    > top)    ? 2 : 0;
    119     mask |= (exclude.right  < right)  ? 4 : 0;
    120     mask |= (exclude.bottom < bottom) ? 8 : 0;
    121 
    122     if (mask == 0) {
    123         // crop entirely covers us
    124         result.clear();
    125     } else {
    126         result = *this;
    127         if (!(mask & (mask - 1))) {
    128             // power-of-2, i.e.: just one bit is set
    129             if (mask & 1) {
    130                 result.right = min(result.right, exclude.left);
    131             } else if (mask & 2) {
    132                 result.bottom = min(result.bottom, exclude.top);
    133             } else if (mask & 4) {
    134                 result.left = max(result.left, exclude.right);
    135             } else if (mask & 8) {
    136                 result.top = max(result.top, exclude.bottom);
    137             }
    138         }
    139     }
    140 
    141     return result;
    142 }
    143 
    144 }; // namespace android
    145