1 /*
2 * Copyright (C) 2017 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 "ConfigManager.h"
17
18 #include "json/json.h"
19
20 #include <fstream>
21 #include <math.h>
22 #include <assert.h>
23
24
25 static const float kDegreesToRadians = M_PI / 180.0f;
26
27
normalizeToPlusMinus180degrees(float theta)28 static float normalizeToPlusMinus180degrees(float theta) {
29 const float wraps = floor((theta+180.0f) / 360.0f);
30 return theta - wraps*360.0f;
31 }
32
33
readChildNodeAsFloat(const char * groupName,const Json::Value & parentNode,const char * childName,float * value)34 static bool readChildNodeAsFloat(const char* groupName,
35 const Json::Value& parentNode,
36 const char* childName,
37 float* value) {
38 // Must have a place to put the value!
39 assert(value);
40
41 Json::Value childNode = parentNode[childName];
42 if (!childNode.isNumeric()) {
43 printf("Missing or invalid field %s in record %s", childName, groupName);
44 return false;
45 }
46
47 *value = childNode.asFloat();
48 return true;
49 }
50
51
initialize(const char * configFileName)52 bool ConfigManager::initialize(const char* configFileName)
53 {
54 bool complete = true;
55
56 // Set up a stream to read in the input file
57 std::ifstream configStream(configFileName);
58
59 // Parse the stream into JSON objects
60 Json::Reader reader;
61 Json::Value rootNode;
62 bool parseOk = reader.parse(configStream, rootNode, false /* don't need comments */);
63 if (!parseOk) {
64 printf("Failed to read configuration file %s\n", configFileName);
65 printf("%s\n", reader.getFormatedErrorMessages().c_str());
66 return false;
67 }
68
69
70 //
71 // Read car information
72 //
73 {
74 Json::Value car = rootNode["car"];
75 if (!car.isObject()) {
76 printf("Invalid configuration format -- we expect a car description\n");
77 return false;
78 }
79 complete &= readChildNodeAsFloat("car", car, "width", &mCarWidth);
80 complete &= readChildNodeAsFloat("car", car, "wheelBase", &mWheelBase);
81 complete &= readChildNodeAsFloat("car", car, "frontExtent", &mFrontExtent);
82 complete &= readChildNodeAsFloat("car", car, "rearExtent", &mRearExtent);
83 }
84
85
86 //
87 // Read display layout information
88 //
89 {
90 Json::Value displayNode = rootNode["display"];
91 if (!displayNode.isObject()) {
92 printf("Invalid configuration format -- we expect a display description\n");
93 return false;
94 }
95 complete &= readChildNodeAsFloat("display", displayNode, "frontRange", &mFrontRangeInCarSpace);
96 complete &= readChildNodeAsFloat("display", displayNode, "rearRange", &mRearRangeInCarSpace);
97 }
98
99
100 //
101 // Car top view texture properties for top down view
102 //
103 {
104 Json::Value graphicNode = rootNode["graphic"];
105 if (!graphicNode.isObject()) {
106 printf("Invalid configuration format -- we expect a graphic description\n");
107 return false;
108 }
109 complete &= readChildNodeAsFloat("graphic", graphicNode, "frontPixel", &mCarGraphicFrontPixel);
110 complete &= readChildNodeAsFloat("display", graphicNode, "rearPixel", &mCarGraphicRearPixel);
111 }
112
113
114 //
115 // Read camera information
116 // NOTE: Missing positions and angles are not reported, but instead default to zero
117 //
118 {
119 Json::Value cameraArray = rootNode["cameras"];
120 if (!cameraArray.isArray()) {
121 printf("Invalid configuration format -- we expect an array of cameras\n");
122 return false;
123 }
124
125 mCameras.reserve(cameraArray.size());
126 for (auto&& node: cameraArray) {
127 // Get data from the configuration file
128 Json::Value nameNode = node.get("cameraId", "MISSING");
129 const char *cameraId = nameNode.asCString();
130
131 Json::Value usageNode = node.get("function", "");
132 const char *function = usageNode.asCString();
133
134 float yaw = node.get("yaw", 0).asFloat();
135 float pitch = node.get("pitch", 0).asFloat();
136 float hfov = node.get("hfov", 0).asFloat();
137 float vfov = node.get("vfov", 0).asFloat();
138
139 // Wrap the direction angles to be in the 180deg to -180deg range
140 // Rotate 180 in yaw if necessary to flip the pitch into the +/-90degree range
141 pitch = normalizeToPlusMinus180degrees(pitch);
142 if (pitch > 90.0f) {
143 yaw += 180.0f;
144 pitch = 180.0f - pitch;
145 }
146 if (pitch < -90.0f) {
147 yaw += 180.0f;
148 pitch = -180.0f + pitch;
149 }
150 yaw = normalizeToPlusMinus180degrees(yaw);
151
152 // Range check the FOV values to ensure they are postive and less than 180degrees
153 if (hfov > 179.0f) {
154 printf("Pathological horizontal field of view %f clamped to 179 degrees\n", hfov);
155 hfov = 179.0f;
156 }
157 if (hfov < 1.0f) {
158 printf("Pathological horizontal field of view %f clamped to 1 degree\n", hfov);
159 hfov = 1.0f;
160 }
161 if (vfov > 179.0f) {
162 printf("Pathological horizontal field of view %f clamped to 179 degrees\n", vfov);
163 vfov = 179.0f;
164 }
165 if (vfov < 1.0f) {
166 printf("Pathological horizontal field of view %f clamped to 1 degree\n", vfov);
167 vfov = 1.0f;
168 }
169
170 // Store the camera info (converting degrees to radians in the process)
171 CameraInfo info;
172 info.position[0] = node.get("x", 0).asFloat();
173 info.position[1] = node.get("y", 0).asFloat();
174 info.position[2] = node.get("z", 0).asFloat();
175 info.yaw = yaw * kDegreesToRadians;
176 info.pitch = pitch * kDegreesToRadians;
177 info.hfov = hfov * kDegreesToRadians;
178 info.vfov = vfov * kDegreesToRadians;
179 info.cameraId = cameraId;
180 info.function = function;
181
182 mCameras.push_back(info);
183 }
184 }
185
186 // If we got this far, we were successful as long as we found all our child fields
187 return complete;
188 }
189