1 /* 2 * Copyright (C) 2015 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 #include "renderstate/Scissor.h" 17 18 #include "Rect.h" 19 20 #include <utils/Log.h> 21 22 namespace android { 23 namespace uirenderer { 24 25 Scissor::Scissor() 26 : mEnabled(false) 27 , mScissorX(0) 28 , mScissorY(0) 29 , mScissorWidth(0) 30 , mScissorHeight(0) { 31 } 32 33 bool Scissor::setEnabled(bool enabled) { 34 if (mEnabled != enabled) { 35 if (enabled) { 36 glEnable(GL_SCISSOR_TEST); 37 } else { 38 glDisable(GL_SCISSOR_TEST); 39 } 40 mEnabled = enabled; 41 return true; 42 } 43 return false; 44 } 45 46 bool Scissor::set(GLint x, GLint y, GLint width, GLint height) { 47 if (mEnabled && (x != mScissorX || y != mScissorY 48 || width != mScissorWidth || height != mScissorHeight)) { 49 50 if (x < 0) { 51 width += x; 52 x = 0; 53 } 54 if (y < 0) { 55 height += y; 56 y = 0; 57 } 58 if (width < 0) { 59 width = 0; 60 } 61 if (height < 0) { 62 height = 0; 63 } 64 glScissor(x, y, width, height); 65 66 mScissorX = x; 67 mScissorY = y; 68 mScissorWidth = width; 69 mScissorHeight = height; 70 71 return true; 72 } 73 return false; 74 } 75 76 void Scissor::set(int viewportHeight, const Rect& clip) { 77 // transform to Y-flipped GL space, and prevent negatives 78 GLint x = std::max(0, (int)clip.left); 79 GLint y = std::max(0, viewportHeight - (int)clip.bottom); 80 GLint width = std::max(0, ((int)clip.right) - x); 81 GLint height = std::max(0, (viewportHeight - (int)clip.top) - y); 82 83 if (x != mScissorX 84 || y != mScissorY 85 || width != mScissorWidth 86 || height != mScissorHeight) { 87 glScissor(x, y, width, height); 88 89 mScissorX = x; 90 mScissorY = y; 91 mScissorWidth = width; 92 mScissorHeight = height; 93 } 94 } 95 96 void Scissor::reset() { 97 mScissorX = mScissorY = mScissorWidth = mScissorHeight = 0; 98 } 99 100 void Scissor::invalidate() { 101 mEnabled = glIsEnabled(GL_SCISSOR_TEST); 102 setEnabled(true); 103 reset(); 104 } 105 106 void Scissor::dump() { 107 ALOGD("Scissor: enabled %d, %d %d %d %d", 108 mEnabled, mScissorX, mScissorY, mScissorWidth, mScissorHeight); 109 } 110 111 } /* namespace uirenderer */ 112 } /* namespace android */ 113 114