From da7d77dd7ed01ceb858554269d0748addbacb969 Mon Sep 17 00:00:00 2001
From: Zack Buhman <zack@buhman.org>
Date: Wed, 2 Jul 2025 20:56:51 -0500
Subject: [PATCH] add twiddle_data_4bpp

---
 example/software_ta_two_volumes.cpp |   3 +-
 holly/region_array.cpp              |   2 -
 tools/twiddle_data_4bpp.cpp         | 104 ++++++++++++++++++++++++++++
 3 files changed, 106 insertions(+), 3 deletions(-)
 create mode 100644 tools/twiddle_data_4bpp.cpp

diff --git a/example/software_ta_two_volumes.cpp b/example/software_ta_two_volumes.cpp
index 3603a4b..b3e2e43 100644
--- a/example/software_ta_two_volumes.cpp
+++ b/example/software_ta_two_volumes.cpp
@@ -48,7 +48,8 @@ void init_texture_memory()
 			 texture_memory_alloc.region_array.start,
 			 texture_memory_alloc.object_list.start);
 
-  background_parameter(0xff222200);
+  background_parameter2(texture_memory_alloc.background[0].start,
+                        0xff000000);
 }
 
 constexpr float half_degree = 0.01745329f / 2.f;
diff --git a/holly/region_array.cpp b/holly/region_array.cpp
index cb69675..5cf8705 100644
--- a/holly/region_array.cpp
+++ b/holly/region_array.cpp
@@ -117,8 +117,6 @@ void region_array2(const uint32_t width,  // in tile units (1 tile unit = 32 pix
   }
 }
 
-#include "printf/printf.h"
-
 void region_array_multipass(const uint32_t width,  // in tile units (1 tile unit = 32 pixels)
                             const uint32_t height, // in tile units (1 tile unit = 32 pixels)
                             const struct opb_size * opb_size,
diff --git a/tools/twiddle_data_4bpp.cpp b/tools/twiddle_data_4bpp.cpp
new file mode 100644
index 0000000..53dde3b
--- /dev/null
+++ b/tools/twiddle_data_4bpp.cpp
@@ -0,0 +1,104 @@
+#include <assert.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <inttypes.h>
+
+#include "../twiddle.hpp"
+
+int read_file(const char * filename, uint8_t ** buf, uint32_t * size_out)
+{
+  FILE * file = fopen(filename, "rb");
+  if (file == NULL) {
+    fprintf(stderr, "fopen(\"%s\", \"rb\"): %s\n", filename, strerror(errno));
+    return -1;
+  }
+
+  int ret;
+  ret = fseek(file, 0L, SEEK_END);
+  if (ret < 0) {
+    fprintf(stderr, "fseek(SEEK_END)");
+    return -1;
+  }
+
+  long offset = ftell(file);
+  if (offset < 0) {
+    fprintf(stderr, "ftell");
+    return -1;
+  }
+  size_t size = offset;
+
+  ret = fseek(file, 0L, SEEK_SET);
+  if (ret < 0) {
+    fprintf(stderr, "fseek(SEEK_SET)");
+    return -1;
+  }
+
+  fprintf(stderr, "read_file: %s size %ld\n", filename, size);
+  *buf = (uint8_t *)malloc(size);
+  size_t fread_size = fread(*buf, 1, size, file);
+  if (fread_size != size) {
+    fprintf(stderr, "fread `%s` short read: %" PRIu64 " ; expected: %" PRIu64 "\n", filename, fread_size, size);
+    return -1;
+  }
+
+  ret = fclose(file);
+  if (ret < 0) {
+    fprintf(stderr, "fclose");
+    return -1;
+  }
+
+  *size_out = size;
+
+  return 0;
+}
+
+int write_file(const char * filename, const uint8_t * buf, uint32_t size)
+{
+  FILE * file = fopen(filename, "wb");
+  if (file == NULL) {
+    fprintf(stderr, "fopen(\"%s\", \"wb\"): %s\n", filename, strerror(errno));
+    return -1;
+  }
+
+  size_t write_size = fwrite(buf, 1, size, file);
+  if (write_size != size) {
+    fprintf(stderr, "fwrite: %d %ld %s\n", size, write_size, strerror(errno));
+    return -1;
+  }
+
+  int ret = fclose(file);
+  if (ret < 0) {
+    fprintf(stderr, "fclose");
+    return -1;
+  }
+
+  return 0;
+}
+
+int main(int argc, const char * argv[])
+{
+  if (argc != 3) {
+    fprintf(stderr, "argc != 3\n");
+    return -1;
+  }
+
+  uint8_t * buf;
+  uint32_t size;
+  int ret = read_file(argv[1], &buf, &size);
+  assert(ret == 0);
+
+  // fixme: add pgm support
+
+  for (int i = 0; i < size; i++) {
+    buf[i] = (buf[i] == 255) ? 1 : 0;
+  }
+
+  uint8_t * twiddle = (uint8_t *)malloc(size / 2);
+  twiddle::texture_4bpp(twiddle, buf, 64, 32);
+
+  ret = write_file(argv[2], twiddle, size / 2);
+  assert(ret == 0);
+}