FPM lock journal style.

1 files changed, 20 insertions, 18 deletions

diff --git a/_log/matrix-digital-rain.md b/_log/matrix-digital-rain.md
index 8512208..f1553e1 100644
--- a/_log/matrix-digital-rain.md
+++ b/_log/matrix-digital-rain.md
@@ -16,44 +16,46 @@ than it needed to be.
 </video>
 
 Moved phosphor decay into the 4th byte of the RGB union--should’ve done this 
-in 2022. What was I thinking.
+in 2022; What was I thinking.
 
 Keeping the RGB union despite portability concerns. All my systems are
 little-endian and the code is cleaner this way.
 
 Fixed Unicode by introducing a charset array. UNICODE(min, max) packs Unicode
-ranges into uint64--low four bytes for start, high four bytes for end.
+ranges into uint64: low four bytes for start, high four bytes for end.
 insert_code() unpacks a random block and picks a character from it:
 
 ```
+#define UNICODE(min, max)  (((uint64_t)max << 32) | min)
+
 static uint64_t glyphs[] = {
     UNICODE(0x0021, 0x007E), /* ASCII */
     UNICODE(0xFF65, 0xFF9F), /* Half-width Katakana */
 };
-```
-
-Full-width Katakana breaks column alignment. Stick to half-width
-(U+FF61-U+FF9F) range. Compile with -DNOKANA to disable Katakana altogether.
-
-blend() simulates phosphor decay by eroding RGB channels toward
-background color:
 
-```
-static inline void blend(matrix *mat, size_t row, size_t col)
+static inline void insert_code(matrix *mat,
+    size_t row, size_t col) 
 {
-    unsigned char *color = mat->rgb[index(mat, row, col)].color;
-    color[R] = color[R] - (color[R] - RGB_BG_RED) / DECAY_MPLIER;
-    color[G] = color[G] - (color[G] - RGB_BG_GRN) / DECAY_MPLIER;
-    color[B] = color[B] - (color[B] - RGB_BG_BLU) / DECAY_MPLIER;
+    uint64_t blk;
+    uint32_t min, max;
+
+    blk = glyphs[(rand() % glyphlen)];
+    min = (uint32_t)blk;
+    max = (uint32_t)(blk >> 32);
+    mat->code[index(mat, row, col)] = rand() % (max - min) + min;
 }
 ```
 
-That's still good. Leaving it alone.
+Full-width Katakana breaks column alignment. Stick to half-width
+(U+FF61-U+FF9F) range. Compile with -DNOKANA to disable Katakana altogether.
+
+blend() is still good. Leaving it alone.
 
 Tossed license and automake cruft. Just `cc -O3 main.c -o matrix` now. Don't
 need the ceremony.
 
-Runs at 2-3% CPU on OpenBSD (T490). No regressions. Fans are quiet.
+Runs at 2-3% CPU on OpenBSD (T490). No cause to measure performance more
+precisely. No regressions. Fans are quiet.
 
 Commit:
-[03f8d87](https://git.asciimx.com/matrix-digital-rain/commit/?id=03f8d87ba7c2e46bd3f3cc4c772fb3a2ac740c92)
+[69a888a](https://git.asciimx.com/matrix-digital-rain/commit/main.c?id=69a888a5b0bc4ef4bce4f86c1556a06f0f131fda)