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Reading SRTM hgt files in JavaScript
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| f = require('fs') | |
| h = f.readFileSync('sfoak_srtm_vox.buf') | |
| // read the (1/4 over, 1/4th down) point, 2nd arg would be 3601* 500 + 100 for 50th x in 250th row (2 bytes per record): | |
| g = new DataView(h, Math.pow(2, 3601)/2, 1000) | |
| > g.getInt16(0, true) | |
| 97 | |
| > g.getInt16(1, true) | |
| 24320 // wrong, next int16 is two bytes over | |
| > g.getInt16(2, true) | |
| 95 // correct | |
| > h = f.readFileSync('N37W123.hgt') | |
| > g = new DataView(h, Math.pow(2, 3601)/2, 1000) | |
| > g.getInt16(0, true) | |
| 24832 // wrong, big endian DataView default useful at last | |
| > g.getInt16(0, false) | |
| 97 //correct |
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