Commit: 4f9478dd4e197ca6e3ccd70482812ab6c267fada
Parent: 643d30a3626fc523afa6d4f8583321d3ec209007
Author: Randy Palamar
Date: Tue, 8 Oct 2024 16:02:47 -0600
implement scientific notation printing; drop stdio.h
Diffstat:
| M | ui.c | | | 4 | ++-- |
| M | util.c | | | 28 | ++++++++++++++++------------ |
2 files changed, 18 insertions(+), 14 deletions(-)
diff --git a/ui.c b/ui.c
@@ -601,7 +601,7 @@ draw_debug_overlay(BeamformerCtx *ctx, Arena arena, Rect r)
draw_text(ctx->font, labels[index], pos, 0, colour_from_normalized(FG_COLOUR));
buf.widx = 0;
- stream_append_f32_e(&buf, cs->last_frame_time[index]);
+ stream_append_f64_e(&buf, cs->last_frame_time[index]);
stream_append_s8(&buf, s8(" [s]"));
v2 txt_fs = measure_text(ctx->font, stream_to_s8(buf));
v2 rpos = {.x = r.pos.x + r.size.w - txt_fs.w, .y = pos.y};
@@ -617,7 +617,7 @@ draw_debug_overlay(BeamformerCtx *ctx, Arena arena, Rect r)
draw_text(ctx->font, totals[i], pos, 0, colour_from_normalized(FG_COLOUR));
buf.widx = 0;
- stream_append_f32_e(&buf, times[i]);
+ stream_append_f64_e(&buf, times[i]);
stream_append_s8(&buf, s8(" [s]"));
v2 txt_fs = measure_text(ctx->font, stream_to_s8(buf));
v2 rpos = {.x = r.pos.x + r.size.w - txt_fs.w, .y = pos.y};
diff --git a/util.c b/util.c
@@ -1,6 +1,4 @@
/* See LICENSE for license details. */
-#include <stdio.h>
-
static void *
mem_clear(u8 *p, u8 c, size len)
{
@@ -120,17 +118,23 @@ stream_append_f64(Stream *s, f64 f, i64 prec)
}
static void
-stream_append_f32_e(Stream *s, f32 f)
+stream_append_f64_e(Stream *s, f64 f)
{
- if (f < 0) {
- stream_append_byte(s, '-');
- f *= -1;
- }
- /* TODO */
- size remaining = s->cap - s->widx;
- s->errors |= remaining <= snprintf(0, 0, "%0.02e", f);
- if (!s->errors)
- s->widx += snprintf((char *)(s->data + s->widx), remaining, "%0.02e", f);
+ /* NOTE: we ignore subnormal numbers for now */
+ union { f64 f; u64 u; } u = {.f = f};
+ f64 log_10_of_2 = 0.301f;
+ i64 exponent = (u.u & (0x7ffULL << 52)) >> 52;
+ f64 scale = (exponent - 1023) * log_10_of_2;
+ u.u &= ~(0x7ffULL << 52);
+ u.u |= (1023ULL << 52);
+
+ if (f == 0) { u.f = 0; scale = 0; }
+ stream_append_f64(s, u.f, 100);
+ stream_append_byte(s, 'e');
+ stream_append_byte(s, scale >= 0? '+' : '-');
+ if (ABS((i64)scale) < 10)
+ stream_append_byte(s, '0');
+ stream_append_u64(s, scale >= 0? scale : -scale);
}
static s8