Put blink code in its own function

[xonotic/xonotic-data.pk3dir.git] / qcsrc / client / miscfunctions.qc

diff --git a/qcsrc/client/miscfunctions.qc b/qcsrc/client/miscfunctions.qc
index bb0bfe12c7642bc09bc595d4982a80fb9913e581..2d0cf212d79f8b856a0d4ab8991f53c50bb6f796 100644 (file)
--- a/qcsrc/client/miscfunctions.qc
+++ b/qcsrc/client/miscfunctions.qc
@@ -214,6 +214,19 @@ vector expandingbox_resize_centered_box_offset(float sz, vector boxsize, float b
        return boxsize * (0.5 * (1 - sz));
 }
 
+// NOTE base is the central value
+// freq: circle frequency, = 2*pi*frequency in hertz
+float blink(float base, float range, float freq)
+{
+       // note:
+       //   RMS = sqrt(base^2 + 0.5 * range^2)
+       // thus
+       //   base = sqrt(RMS^2 - 0.5 * range^2)
+       // ensure RMS == 1
+
+       return base + range * cos(time * freq);
+}
+
 void drawborderlines(float thickness, vector pos, vector dim, vector color, float theAlpha, float drawflag)
 {
        vector line_dim = '0 0 0';