完成主要交互、高性能组件、国际化和A型传感器数据包接收

src/nice_ticks.h

@@ -0,0 +1,53 @@
+#ifndef NICE_TICKS
+#define NICE_TICKS
+
+#include <cmath>
+#include <vector>
+
+inline double niceNumber(double x, bool round) {
+    const double expv = std::floor(std::log10(x));
+    const double f = x / std::pow(10.0, expv);
+    double nf;
+    if (round) {
+        if (f < 1.5) nf = 1.0;
+        else if (f < 3.0) nf = 2.0;
+        else if (f < 7.0) nf = 5.0;
+        else nf = 10.0;
+    } else {
+        if (f <= 1.0) nf = 1.0;
+        else if (f <= 2.0) nf = 2.0;
+        else if (f <= 5.0) nf = 5.0;
+        else nf = 10.0;
+    }
+    return nf * std::pow(10.0, expv);
+}
+
+struct NiceTicksResult {
+    double niceMin = 0;
+    double niceMax = 1;
+    double step = 0.2;
+    std::vector<double> ticks;
+};
+
+inline NiceTicksResult niceTicks(double minv, double maxv, int maxTicks = 5) {
+    NiceTicksResult r;
+    if (minv == maxv) {
+        // 给一个小范围
+        minv -= 1.0;
+        maxv += 1.0;
+    }
+    const double range = niceNumber(maxv - minv, false);
+    const double step = niceNumber(range / (maxTicks - 1), true);
+    const double niceMin = std::floor(minv / step) * step;
+    const double niceMax = std::ceil(maxv / step) * step;
+
+    r.niceMin = niceMin;
+    r.niceMax = niceMax;
+    r.step = step;
+
+    for (double v = niceMin; v <= niceMax + 0.5 * step; v += step) {
+        r.ticks.push_back(v);
+    }
+    return r;
+}
+#endif