| 158 | } |
| 159 | |
| 160 | bool GenerateYAxisChartData(uint32_t height, double minMetersPerPxl, vector<double> const & altitudeDataM, |
| 161 | vector<double> & yAxisDataPxl) |
| 162 | { |
| 163 | if (altitudeDataM.empty()) |
| 164 | { |
| 165 | yAxisDataPxl.clear(); |
| 166 | return true; |
| 167 | } |
| 168 | |
| 169 | uint32_t constexpr kHeightIndentPxl = 2; |
| 170 | uint32_t heightIndentPxl = kHeightIndentPxl; |
| 171 | if (height <= 2 * kHeightIndentPxl) |
| 172 | { |
| 173 | LOG(LERROR, ("Chart height is less or equal than 2 * kHeightIndentPxl (", 2 * kHeightIndentPxl, ")")); |
| 174 | heightIndentPxl = 0; |
| 175 | } |
| 176 | |
| 177 | auto const minMaxAltitudeIt = minmax_element(altitudeDataM.begin(), altitudeDataM.end()); |
| 178 | double const minAltM = *minMaxAltitudeIt.first; |
| 179 | double const maxAltM = *minMaxAltitudeIt.second; |
| 180 | double const deltaAltM = maxAltM - minAltM; |
| 181 | uint32_t const drawHeightPxl = height - 2 * heightIndentPxl; |
| 182 | double const metersPerPxl = max(minMetersPerPxl, deltaAltM / static_cast<double>(drawHeightPxl)); |
| 183 | if (metersPerPxl == 0.0) |
| 184 | { |
| 185 | LOG(LERROR, ("metersPerPxl == 0.0")); |
| 186 | return false; |
| 187 | } |
| 188 | // int avoids double errors which make freeHeightSpacePxl slightly less than zero. |
| 189 | int const deltaAltPxl = deltaAltM / metersPerPxl; |
| 190 | double const freeHeightSpacePxl = drawHeightPxl - deltaAltPxl; |
| 191 | if (freeHeightSpacePxl < 0 || freeHeightSpacePxl > drawHeightPxl) |
| 192 | { |
| 193 | LOG(LERROR, ("Number of pixels free of chart points (", freeHeightSpacePxl, |
| 194 | ") is below zero or greater than the number of pixels for the chart (", drawHeightPxl, ").")); |
| 195 | return false; |
| 196 | } |
| 197 | |
| 198 | double const maxAltPxl = maxAltM / metersPerPxl; |
| 199 | yAxisDataPxl.assign(altitudeDataM.cbegin(), altitudeDataM.cend()); |
| 200 | ScaleChartData(yAxisDataPxl, 1.0 / metersPerPxl); |
| 201 | ReflectChartData(yAxisDataPxl); |
| 202 | ShiftChartData(yAxisDataPxl, maxAltPxl + heightIndentPxl + freeHeightSpacePxl / 2.0); |
| 203 | |
| 204 | return true; |
| 205 | } |
| 206 | |
| 207 | bool GenerateChartByPoints(uint32_t width, uint32_t height, vector<m2::PointD> const & geometry, MapStyle mapStyle, |
| 208 | vector<uint8_t> & frameBuffer) |