From 9a5602f287e612c595663ec10bf7b6d5368414db Mon Sep 17 00:00:00 2001
From: Zack Buhman <zack@buhman.org>
Date: Sun, 1 Dec 2024 15:53:03 -0600
Subject: [PATCH] day1

---
 .gitignore           |   21 +
 Makefile             |   12 +
 aoc.mk               |   25 ++
 day1/input.txt       | 1000 ++++++++++++++++++++++++++++++++++++++++++
 day1/input.txt.h     |   15 +
 day1/sample1.txt     |    6 +
 day1/sample1.txt.h   |   15 +
 day1/sample2.txt     |    1 +
 day1/solution.c      |   85 ++++
 dreamcast            |    1 +
 heapsort.c           |   58 +++
 heapsort.h           |   11 +
 input.h              |   12 +
 input_dreamcast.c    |   50 +++
 input_stdlib.c       |   43 ++
 minmax.h             |    4 +
 parse.c              |   45 ++
 parse.h              |   12 +
 printf.c             |  123 ++++++
 printf.h             |   22 +
 putchar_dreamcast.c  |    0
 runner.c             |   34 ++
 runner.h             |   17 +
 runner_dreamcast.cpp |  282 ++++++++++++
 unparse.c            |  116 +++++
 unparse.h            |   12 +
 26 files changed, 2022 insertions(+)
 create mode 100755 .gitignore
 create mode 100644 Makefile
 create mode 100644 aoc.mk
 create mode 100644 day1/input.txt
 create mode 100644 day1/input.txt.h
 create mode 100644 day1/sample1.txt
 create mode 100644 day1/sample1.txt.h
 create mode 120000 day1/sample2.txt
 create mode 100644 day1/solution.c
 create mode 120000 dreamcast
 create mode 100644 heapsort.c
 create mode 100644 heapsort.h
 create mode 100644 input.h
 create mode 100644 input_dreamcast.c
 create mode 100644 input_stdlib.c
 create mode 100644 minmax.h
 create mode 100644 parse.c
 create mode 100644 parse.h
 create mode 100644 printf.c
 create mode 100644 printf.h
 create mode 100644 putchar_dreamcast.c
 create mode 100644 runner.c
 create mode 100644 runner.h
 create mode 100644 runner_dreamcast.cpp
 create mode 100644 unparse.c
 create mode 100644 unparse.h

diff --git a/.gitignore b/.gitignore
new file mode 100755
index 0000000..6a10363
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,21 @@
+*.pyc
+__pycache__
+.~*
+*.BIN
+*.bin
+*.elf
+*.d
+*.iso
+*.cdi
+*.o
+*.out
+*.gch
+scramble
+cdi4dc
+tools/ttf_outline
+tools/ttf_bitmap
+tools/ftdi_transfer
+k_means_vq
+*.blend1
+*.scramble
+*.FCStd1
\ No newline at end of file
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..0674557
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,12 @@
+all: $(patsubst %.cpp,%.elf,$(wildcard example/*.cpp))
+
+include dreamcast/base.mk
+include dreamcast/common.mk
+include dreamcast/headers.mk
+
+MAKEFILE_PATH := $(abspath $(firstword $(MAKEFILE_LIST)))
+CFLAGS += -I$(dir $(MAKEFILE_PATH))
+CFLAGS += -I$(dir $(MAKEFILE_PATH))dreamcast/
+LIB ?= $(dir $(MAKEFILE_PATH))dreamcast
+
+include aoc.mk
diff --git a/aoc.mk b/aoc.mk
new file mode 100644
index 0000000..bdb925f
--- /dev/null
+++ b/aoc.mk
@@ -0,0 +1,25 @@
+OBJ = \
+	parse.o \
+	heapsort.o \
+	printf.o \
+	runner.o \
+	unparse.o
+
+DREAMCAST_OBJ = \
+	runner_dreamcast.o \
+	input_dreamcast.o \
+	$(LIB)/holly/core.o \
+	$(LIB)/holly/region_array.o \
+	$(LIB)/holly/background.o \
+	$(LIB)/holly/ta_fifo_polygon_converter.o \
+	$(LIB)/holly/video_output.o \
+	$(LIB)/font/dejavusansmono/dejavusansmono.data.o \
+	$(LIB)/sh7091/serial.o
+
+DAY1_OBJ = \
+	day1/sample1.txt.o \
+	day1/input.txt.o \
+	day1/solution.o
+
+aoc.elf: LDSCRIPT = $(LIB)/main.lds
+aoc.elf: $(START_OBJ) $(OBJ) $(DREAMCAST_OBJ) $(DAY1_OBJ)
diff --git a/day1/input.txt b/day1/input.txt
new file mode 100644
index 0000000..6192278
--- /dev/null
+++ b/day1/input.txt
@@ -0,0 +1,1000 @@
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diff --git a/day1/input.txt.h b/day1/input.txt.h
new file mode 100644
index 0000000..84489a5
--- /dev/null
+++ b/day1/input.txt.h
@@ -0,0 +1,15 @@
+#pragma once
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern uint32_t _binary_day1_input_txt_start __asm("_binary_day1_input_txt_start");
+extern uint32_t _binary_day1_input_txt_end __asm("_binary_day1_input_txt_end");
+extern uint32_t _binary_day1_input_txt_size __asm("_binary_day1_input_txt_size");
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/day1/sample1.txt b/day1/sample1.txt
new file mode 100644
index 0000000..b8af9ad
--- /dev/null
+++ b/day1/sample1.txt
@@ -0,0 +1,6 @@
+3   4
+4   3
+2   5
+1   3
+3   9
+3   3
diff --git a/day1/sample1.txt.h b/day1/sample1.txt.h
new file mode 100644
index 0000000..003dbe0
--- /dev/null
+++ b/day1/sample1.txt.h
@@ -0,0 +1,15 @@
+#pragma once
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern uint32_t _binary_day1_sample1_txt_start __asm("_binary_day1_sample1_txt_start");
+extern uint32_t _binary_day1_sample1_txt_end __asm("_binary_day1_sample1_txt_end");
+extern uint32_t _binary_day1_sample1_txt_size __asm("_binary_day1_sample1_txt_size");
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/day1/sample2.txt b/day1/sample2.txt
new file mode 120000
index 0000000..0705e8e
--- /dev/null
+++ b/day1/sample2.txt
@@ -0,0 +1 @@
+sample1.txt
\ No newline at end of file
diff --git a/day1/solution.c b/day1/solution.c
new file mode 100644
index 0000000..0935cfb
--- /dev/null
+++ b/day1/solution.c
@@ -0,0 +1,85 @@
+#include "input.h"
+#include "parse.h"
+#include "heapsort.h"
+
+struct list {
+  int left[1000];
+  int right[1000];
+};
+
+int parse_input(const char * input, int length, struct list * list)
+{
+  const char * end = input + length;
+
+  int i = 0;
+  while (input < end) {
+    input = parse_base10(input, &list->left[i]);
+    input = parse_skip(input, ' ');
+    input = parse_base10(input, &list->right[i]);
+    input = parse_skip(input, '\n');
+    i++;
+  }
+
+  return i;
+}
+
+int abs(int n)
+{
+  if (n < 0)
+    return -n;
+  else
+    return n;
+}
+
+int day1_part1(char * input, int length)
+{
+  struct list list;
+  int list_length = parse_input(input, length, &list);
+
+  heapsort(list.left, list_length);
+  heapsort(list.right, list_length);
+
+  int sum = 0;
+  for (int i = 0; i < list_length; i++) {
+    int distance = abs(list.left[i] - list.right[i]);
+    sum += distance;
+  }
+
+  return sum;
+}
+
+int day1_part2(char * input, int length)
+{
+  struct list list;
+  int list_length = parse_input(input, length, &list);
+
+  heapsort(list.left, list_length);
+  heapsort(list.right, list_length);
+
+  int i = 0;
+  int j = 0;
+
+  int sum = 0;
+
+  while (i < list_length) {
+    int n = list.left[i];
+    int mul_l = 1;
+    while (list.left[i + mul_l] == n) {
+      mul_l += 1;
+    }
+    i += mul_l;
+
+    while (list.right[j] < n) {
+      j++;
+    }
+    int mul_r = 0;
+    while (list.right[j + mul_r] == n) {
+      mul_r += 1;
+    }
+    j += mul_r;
+
+    sum += n * mul_l * mul_r;
+  }
+
+  return sum;
+}
diff --git a/dreamcast b/dreamcast
new file mode 120000
index 0000000..c64555a
--- /dev/null
+++ b/dreamcast
@@ -0,0 +1 @@
+../dreamcast
\ No newline at end of file
diff --git a/heapsort.c b/heapsort.c
new file mode 100644
index 0000000..9ef1814
--- /dev/null
+++ b/heapsort.c
@@ -0,0 +1,58 @@
+#include "heapsort.h"
+
+static inline void swap(int * a, int * b)
+{
+  int temp = *a;
+  *a = *b;
+  *b = temp;
+}
+
+static inline int left_child_index(int i)
+{
+  return 2 * i + 1;
+}
+
+void heapsort(int * l, int length)
+{
+  int start = length / 2;
+  int end = length;
+  while (end > 1) {
+    if (start > 0) {
+      start = start - 1;
+    } else {
+      end = end - 1;
+      swap(&l[end], &l[0]);
+    }
+
+    int root = start;
+    while (left_child_index(root) < end) {
+      int child = left_child_index(root);
+      int right_child = child + 1;
+      if (right_child < end && l[child] < l[right_child]) {
+        child = right_child;
+      }
+      if (l[root] < l[child]) {
+        swap(&l[root], &l[child]);
+        root = child;
+      } else {
+        break;
+      }
+    }
+  }
+}
+
+#ifdef HEAPSORT_TEST
+#include <stdio.h>
+
+int main()
+{
+  int l[] = {3, 5, 1, 8, 2, 8, 7, 5, 4, 9};
+  int l_length = (sizeof (l)) / (sizeof (l[0]));
+  heapsort(l, l_length);
+
+  for (int i = 0; i < l_length; i++) {
+    printf("%d ", l[i]);
+  }
+  printf("\n");
+}
+#endif
diff --git a/heapsort.h b/heapsort.h
new file mode 100644
index 0000000..7ad499a
--- /dev/null
+++ b/heapsort.h
@@ -0,0 +1,11 @@
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void heapsort(int * l, int length);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/input.h b/input.h
new file mode 100644
index 0000000..20f3ad9
--- /dev/null
+++ b/input.h
@@ -0,0 +1,12 @@
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void open_input(int day, char ** buf, int * length);
+void open_sample(int day, int part, char ** buf, int * length);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/input_dreamcast.c b/input_dreamcast.c
new file mode 100644
index 0000000..9bed9f9
--- /dev/null
+++ b/input_dreamcast.c
@@ -0,0 +1,50 @@
+#include <stdint.h>
+#include <stddef.h>
+
+#include "input.h"
+
+#include "day1/sample1.txt.h"
+#include "day1/input.txt.h"
+
+struct start_size {
+  char * start;
+  uint32_t size;
+};
+
+static struct start_size input[] = {
+  { (  char *)&_binary_day1_input_txt_start,
+    (uint32_t)&_binary_day1_input_txt_size   },
+};
+
+static struct start_size sample[][2] = {
+  {
+    { (  char *)&_binary_day1_sample1_txt_start,
+      (uint32_t)&_binary_day1_sample1_txt_size   },
+    { (  char *)&_binary_day1_sample1_txt_start,
+      (uint32_t)&_binary_day1_sample1_txt_size   },
+  },
+};
+
+const int input_size = (sizeof (input)) / (sizeof (input[0]));
+
+void open_input(int day, char ** buf, int * length)
+{
+  if (day < 1 || day > input_size) {
+    *buf = NULL;
+    *length = 0;
+  } else {
+    *buf    = input[day - 1].start;
+    *length = input[day - 1].size;
+  }
+}
+
+void open_sample(int day, int part, char ** buf, int * length)
+{
+  if (day < 1 || day > input_size || part < 1 || part > 2) {
+    *buf = NULL;
+    *length = 0;
+  } else {
+    *buf    = sample[day - 1][part - 1].start;
+    *length = sample[day - 1][part - 1].size;
+  }
+}
diff --git a/input_stdlib.c b/input_stdlib.c
new file mode 100644
index 0000000..0795427
--- /dev/null
+++ b/input_stdlib.c
@@ -0,0 +1,43 @@
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "input.h"
+
+static void read_file(const char * filename, char ** buf, int * length)
+{
+  FILE * f = fopen(filename, "rb");
+  assert(f != NULL);
+  int ret = fseek(f, 0L, SEEK_END);
+  assert(ret >= 0);
+  long size = ftell(f);
+  assert(size > 0);
+  rewind(f);
+
+  *buf = malloc(size);
+
+  size_t read = fread(*buf, 1, size, f);
+  assert(read == size);
+
+  *length = size;
+}
+
+void open_input(int day, char ** buf, int * length)
+{
+  char filename[1024];
+
+  const char * format = "day%d/input.txt";
+  snprintf(filename, (sizeof (filename)), format, day);
+
+  read_file(filename, buf, length);
+}
+
+void open_sample(int day, int part, char ** buf, int * length)
+{
+  char filename[1024];
+
+  const char * format = "day%d/sample%d.txt";
+  snprintf(filename, (sizeof (filename)), format, day, part);
+
+  read_file(filename, buf, length);
+}
diff --git a/minmax.h b/minmax.h
new file mode 100644
index 0000000..df4c506
--- /dev/null
+++ b/minmax.h
@@ -0,0 +1,4 @@
+#pragma once
+
+#define min(a, b) ( (a < b) ? a : b )
+#define max(a, b) ( (a > b) ? a : b )
diff --git a/parse.c b/parse.c
new file mode 100644
index 0000000..9b333da
--- /dev/null
+++ b/parse.c
@@ -0,0 +1,45 @@
+#include <stdbool.h>
+
+#include "parse.h"
+
+const char * parse_skip(const char * s, char c)
+{
+  while (*s == c) {
+    s++;
+  }
+  return s;
+}
+
+static int base10_digit(char c)
+{
+  switch (c) {
+  case '0': return 0;
+  case '1': return 1;
+  case '2': return 2;
+  case '3': return 3;
+  case '4': return 4;
+  case '5': return 5;
+  case '6': return 6;
+  case '7': return 7;
+  case '8': return 8;
+  case '9': return 9;
+  default: return -1;
+  }
+}
+
+const char * parse_base10(const char * s, int * n)
+{
+  *n = 0;
+
+  while (true) {
+    int digit = base10_digit(*s);
+    if (digit == -1)
+      break;
+
+    *n *= 10;
+    *n += digit;
+    s++;
+  }
+
+  return s;
+}
diff --git a/parse.h b/parse.h
new file mode 100644
index 0000000..a468f4f
--- /dev/null
+++ b/parse.h
@@ -0,0 +1,12 @@
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+const char * parse_skip(const char * s, char c);
+const char * parse_base10(const char * s, int * n);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/printf.c b/printf.c
new file mode 100644
index 0000000..f90dbd8
--- /dev/null
+++ b/printf.c
@@ -0,0 +1,123 @@
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdarg.h>
+
+#include "parse.h"
+#include "unparse.h"
+#include "printf.h"
+
+enum format_type {
+  FORMAT_BASE10,
+  FORMAT_BASE16,
+  FORMAT_STRING,
+  FORMAT_PERCENT,
+};
+
+struct format {
+  enum format_type type;
+  int pad_length;
+  char fill_char;
+};
+
+static const char * parse_escape(const char * format, struct format * ft);
+
+static const char * parse_fill_pad(const char * format, struct format * ft)
+{
+  if (*format == 0)
+    return format;
+  ft->fill_char = *format++;
+  format = parse_base10(format, &ft->pad_length);
+  return parse_escape(format, ft);
+}
+
+static const char * parse_escape(const char * format, struct format * ft)
+{
+  switch (*format) {
+  case 0:
+    return format;
+  case 'd':
+    ft->type = FORMAT_BASE10;
+    return format + 1;
+  case 'x':
+    ft->type = FORMAT_BASE16;
+    return format + 1;
+  case 's':
+    ft->type = FORMAT_STRING;
+    return format + 1;
+  case '%':
+    ft->type = FORMAT_PERCENT;
+    return format + 1;
+  default:
+    return parse_fill_pad(format, ft);
+  }
+}
+
+struct output_buffer global_output_buffer = {0};
+
+void _printf(const char * format, ...)
+{
+  va_list args;
+  va_start(args, format);
+
+  while (true) {
+    if (*format == 0)
+      break;
+
+    switch (*format) {
+    case '%':
+      {
+        struct format ft = {0};
+        format = parse_escape(format + 1, &ft);
+        switch (ft.type) {
+        case FORMAT_BASE10:
+          {
+            int32_t num = va_arg(args, int32_t);
+            char * s = &global_output_buffer.buf[global_output_buffer.buf_ix];
+            int offset = unparse_base10(s, num, ft.pad_length, ft.fill_char);
+            global_output_buffer.buf_ix += offset;
+          }
+          break;
+        case FORMAT_BASE16:
+          {
+            uint32_t num = va_arg(args, uint32_t);
+            char * s = &global_output_buffer.buf[global_output_buffer.buf_ix];
+            int offset = unparse_base16(s, num, ft.pad_length, ft.fill_char);
+            global_output_buffer.buf_ix += offset;
+          }
+          break;
+        case FORMAT_STRING:
+          {
+            const char * s = va_arg(args, const char *);
+            while (*s != 0) {
+              global_output_buffer.buf[global_output_buffer.buf_ix++] = *s++;
+            }
+          }
+          break;
+        case FORMAT_PERCENT:
+          global_output_buffer.buf[global_output_buffer.buf_ix++] = '%';
+          break;
+        }
+      }
+      break;
+    default:
+      global_output_buffer.buf[global_output_buffer.buf_ix++] = *format++;
+      break;
+    }
+  }
+
+  va_end(args);
+}
+
+#ifdef PRINTF_TEST
+#include <stdio.h>
+
+int main()
+{
+  _printf("test `% 8d` %s foobar\n", 1234, "hello");
+  _printf("test2 `% 8d` %s foobar\n", -1234, "bar");
+
+  global_output_buffer.buf[global_output_buffer.buf_ix] = 0;
+
+  puts(global_output_buffer.buf);
+}
+#endif
diff --git a/printf.h b/printf.h
new file mode 100644
index 0000000..7bf8196
--- /dev/null
+++ b/printf.h
@@ -0,0 +1,22 @@
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void _printf(const char * format, ...);
+
+#ifndef PRINTF_TEST
+#define printf(...) _printf(__VA_ARGS__)
+#endif
+
+struct output_buffer {
+  int buf_ix;
+  char buf[16 * 1024];
+};
+
+extern struct output_buffer global_output_buffer;
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/putchar_dreamcast.c b/putchar_dreamcast.c
new file mode 100644
index 0000000..e69de29
diff --git a/runner.c b/runner.c
new file mode 100644
index 0000000..4738cd9
--- /dev/null
+++ b/runner.c
@@ -0,0 +1,34 @@
+#include "printf.h"
+#include "input.h"
+#include "runner.h"
+
+int day1_part1(char * input, int length);
+int day1_part2(char * input, int length);
+
+typedef int (* part_func)(char * input, int length);
+
+part_func solution[][2] = {
+  {day1_part1, day1_part2},
+};
+const int solution_days = (sizeof (solution)) / (sizeof (solution[0]));
+
+bool runner_tick(struct runner_state * runner_state)
+{
+  int part = runner_state->tick % 2;
+  int day = runner_state->tick / 2;
+
+  if (day >= solution_days)
+    return true;
+
+  char * buf;
+  int length;
+  //open_sample(day + 1, part + 1, &buf, &length);
+  open_input(day + 1, &buf, &length);
+  int answer = solution[day][part](buf, length);
+
+  printf("day %d part %d: %d\n", day + 1, part + 1, answer);
+
+  runner_state->tick += 1;
+
+  return false;
+}
diff --git a/runner.h b/runner.h
new file mode 100644
index 0000000..682caf9
--- /dev/null
+++ b/runner.h
@@ -0,0 +1,17 @@
+#pragma once
+
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct runner_state {
+  int tick;
+};
+
+bool runner_tick(struct runner_state * runner_state);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/runner_dreamcast.cpp b/runner_dreamcast.cpp
new file mode 100644
index 0000000..47a99b7
--- /dev/null
+++ b/runner_dreamcast.cpp
@@ -0,0 +1,282 @@
+#include <cstdint>
+
+#include "holly/texture_memory_alloc2.hpp"
+#include "holly/isp_tsp.hpp"
+#include "holly/ta_fifo_polygon_converter.hpp"
+#include "holly/ta_parameter.hpp"
+#include "holly/ta_global_parameter.hpp"
+#include "holly/ta_vertex_parameter.hpp"
+#include "holly/ta_bits.hpp"
+#include "holly/background.hpp"
+#include "holly/region_array.hpp"
+#include "holly/holly.hpp"
+#include "holly/core.hpp"
+#include "holly/core_bits.hpp"
+#include "holly/video_output.hpp"
+
+#include "sh7091/store_queue.hpp"
+#include "sh7091/serial.hpp"
+
+#include "font/font.hpp"
+#include "font/dejavusansmono/dejavusansmono.data.h"
+
+#include "palette.hpp"
+
+#include "printf.h"
+#include "runner.h"
+
+struct vertex {
+  float x;
+  float y;
+  float z;
+  float u;
+  float v;
+};
+
+const struct vertex strip_vertices[4] = {
+  // [ position       ]  [ uv coordinates ]
+  { 0.f,  1.f,  0.f, 0.f, 1.f, },
+  { 0.f,  0.f,  0.f, 0.f, 0.f, },
+  { 1.f,  1.f,  0.f, 1.f, 1.f, },
+  { 1.f,  0.f,  0.f, 1.f, 0.f, },
+};
+constexpr uint32_t strip_length = (sizeof (strip_vertices)) / (sizeof (struct vertex));
+
+
+void transform_start(const uint32_t texture_width, uint32_t texture_height)
+{
+  const uint32_t parameter_control_word = para_control::para_type::polygon_or_modifier_volume
+                                        | para_control::list_type::translucent
+                                        | obj_control::col_type::packed_color
+                                        | obj_control::texture;
+
+  const uint32_t isp_tsp_instruction_word = isp_tsp_instruction_word::depth_compare_mode::greater
+                                          | isp_tsp_instruction_word::culling_mode::no_culling;
+
+  const uint32_t tsp_instruction_word = tsp_instruction_word::src_alpha_instr::src_alpha
+                                      | tsp_instruction_word::dst_alpha_instr::one
+                                      | tsp_instruction_word::fog_control::no_fog
+                                      | tsp_instruction_word::use_alpha
+                                      | tsp_instruction_word::texture_u_size::from_int(texture_width)
+                                      | tsp_instruction_word::texture_v_size::from_int(texture_height);
+
+  const uint32_t texture_address = texture_memory_alloc::texture.start;
+  const uint32_t texture_control_word = texture_control_word::pixel_format::_8bpp_palette
+                                      | texture_control_word::scan_order::twiddled
+                                      | texture_control_word::texture_address(texture_address / 8);
+
+  *reinterpret_cast<ta_global_parameter::polygon_type_0 *>(store_queue) =
+    ta_global_parameter::polygon_type_0(parameter_control_word,
+                                        isp_tsp_instruction_word,
+                                        tsp_instruction_word,
+                                        texture_control_word,
+                                        0, // data_size_for_sort_dma
+                                        0  // next_address_for_sort_dma
+                                        );
+  sq_transfer_32byte(ta_fifo_polygon_converter);
+}
+
+int32_t transform_char(const uint32_t texture_width,
+                       const uint32_t texture_height,
+                       const uint32_t first_char_code,
+                       const glyph * glyphs,
+                       const char c,
+                       int32_t horizontal_advance,
+                       int32_t vertical_advance)
+{
+  auto& glyph = glyphs[c - first_char_code];
+
+  for (uint32_t i = 0; i < strip_length; i++) {
+    float x = strip_vertices[i].x;
+    float y = strip_vertices[i].y;
+    float z = strip_vertices[i].z;
+
+    x *= glyph.bitmap.width;
+    y *= glyph.bitmap.height;
+    x += (float)(horizontal_advance + glyph.metrics.horiBearingX) / 64.0;
+    y += (float)(vertical_advance - glyph.metrics.horiBearingY) / 64.0;
+    z = 1.f / (z + 10.f);
+
+    float u = strip_vertices[i].u;
+    float v = strip_vertices[i].v;
+    u *= glyph.bitmap.width;
+    v *= glyph.bitmap.height;
+    u += glyph.bitmap.x;
+    v += glyph.bitmap.y;
+    u = u / static_cast<float>(texture_width);
+    v = v / static_cast<float>(texture_height);
+
+    bool end_of_strip = i == strip_length - 1;
+    *reinterpret_cast<ta_vertex_parameter::polygon_type_3 *>(store_queue) =
+      ta_vertex_parameter::polygon_type_3(polygon_vertex_parameter_control_word(end_of_strip),
+                                          x, y, z,
+                                          u, v,
+                                          0, // base_color
+                                          0  // offset_color
+                                          );
+    sq_transfer_32byte(ta_fifo_polygon_converter);
+  }
+
+  return glyph.metrics.horiAdvance;
+}
+
+void transfer_scene(const struct font * font,
+                    const struct glyph * glyphs)
+{
+  transform_start(font->texture_width, font->texture_height);
+
+  int32_t horizontal_advance = font->face_metrics.max_advance / 5; // 26.6 fixed point
+  int32_t vertical_advance = font->face_metrics.height; // 26.6 fixed point
+
+  for (int i = 0; i < global_output_buffer.buf_ix; i++) {
+    char c = global_output_buffer.buf[i];
+    if (c < 0x20 && c > 0x7f) {
+      continue;
+    } else if (c == '\n') {
+      horizontal_advance = font->face_metrics.max_advance / 5;
+      vertical_advance += font->face_metrics.height;
+    } else {
+      horizontal_advance += transform_char(font->texture_width,
+                                           font->texture_height,
+                                           font->first_char_code,
+                                           glyphs,
+                                           c,
+                                           horizontal_advance,
+                                           vertical_advance);
+    }
+  }
+
+  *reinterpret_cast<ta_global_parameter::end_of_list *>(store_queue) =
+    ta_global_parameter::end_of_list(para_control::para_type::end_of_list);
+  sq_transfer_32byte(ta_fifo_polygon_converter);
+}
+
+void copy_font(const uint8_t * src,
+               const uint32_t z_curve_max_ix)
+{
+  auto texture = reinterpret_cast<volatile uint32_t *>(&texture_memory64[texture_memory_alloc::texture.start / 4]);
+
+  for (uint32_t i = 0; i < z_curve_max_ix / 4; i++) {
+    texture[i] = reinterpret_cast<const uint32_t *>(src)[i];
+  }
+}
+
+int main()
+{
+  serial::init(0);
+  serial::string("framebuffer: ");
+  serial::integer<uint32_t>((uint32_t)&texture_memory32[texture_memory_alloc::framebuffer[0].start / 4]);
+
+  constexpr uint32_t ta_alloc = ta_alloc_ctrl::pt_opb::no_list
+			      | ta_alloc_ctrl::tm_opb::no_list
+			      | ta_alloc_ctrl::t_opb::_32x4byte
+			      | ta_alloc_ctrl::om_opb::no_list
+                              | ta_alloc_ctrl::o_opb::no_list;
+
+  constexpr int render_passes = 1;
+  constexpr struct opb_size opb_size[render_passes] = {
+    {
+      .opaque = 0,
+      .opaque_modifier = 0,
+      .translucent = 32 * 4,
+      .translucent_modifier = 0,
+      .punch_through = 0
+    }
+  };
+
+  holly.SOFTRESET = softreset::pipeline_soft_reset
+		  | softreset::ta_soft_reset;
+  holly.SOFTRESET = 0;
+
+  core_init();
+
+  constexpr int framebuffer_width = 640;
+  constexpr int framebuffer_height = 480;
+  constexpr int tile_width = framebuffer_width / 32;
+  constexpr int tile_height = framebuffer_height / 32;
+
+  region_array_multipass(tile_width,
+			 tile_height,
+			 opb_size,
+			 render_passes,
+			 texture_memory_alloc::region_array[0].start,
+			 texture_memory_alloc::object_list[0].start);
+  region_array_multipass(tile_width,
+			 tile_height,
+			 opb_size,
+			 render_passes,
+			 texture_memory_alloc::region_array[1].start,
+			 texture_memory_alloc::object_list[1].start);
+
+  background_parameter2(texture_memory_alloc::background[0].start,
+			0xff220033);
+  background_parameter2(texture_memory_alloc::background[1].start,
+			0xff220033);
+
+  auto font = reinterpret_cast<const struct font *>(&_binary_font_dejavusansmono_dejavusansmono_data_start);
+  auto glyphs = reinterpret_cast<const struct glyph *>(&font[1]);
+  auto texture = reinterpret_cast<const uint8_t *>(&glyphs[font->glyph_count]);
+
+  copy_font(texture, font->max_z_curve_ix);
+  palette_data<256>();
+
+  int ta = -1;
+  int core = -2;
+
+  struct runner_state runner_state = {0};
+
+  video_output::set_mode_vga();
+
+  bool done = false;
+
+  while (true) {
+    if (core >= 0) {
+      // core = 0  ; core = 1
+      // ta = 1    ; ta = 0
+      core_wait_end_of_render_video();
+      while (!spg_status::vsync(holly.SPG_STATUS));
+      holly.FB_R_SOF1 = texture_memory_alloc::framebuffer[core].start;
+      while (spg_status::vsync(holly.SPG_STATUS));
+    }
+
+    if (core == 0) {
+      if (done == true)
+        break;
+      done = runner_tick(&runner_state);
+    }
+
+    // core = -2 ; core = 1 ; core = 0
+    // ta = -1   ; ta = 0   ; ta = 1
+    core += 1;
+    ta += 1;
+    if (core > 1) core = 0;
+    if (ta > 1) ta = 0;
+
+    if (core >= 0) {
+      // core = 1 ; core = 0
+      // ta = 0   ; ta = 1
+      ta_wait_translucent_list();
+
+      core_start_render2(texture_memory_alloc::region_array[core].start,
+			 texture_memory_alloc::isp_tsp_parameters[core].start,
+			 texture_memory_alloc::background[core].start,
+			 texture_memory_alloc::framebuffer[core].start,
+			 framebuffer_width);
+    }
+
+
+    // core = -1 ; core = 1 ; core = 0
+    // ta = 0    ; ta = 0   ; ta = 1
+    ta_polygon_converter_init2(texture_memory_alloc::isp_tsp_parameters[ta].start,
+			       texture_memory_alloc::isp_tsp_parameters[ta].end,
+			       texture_memory_alloc::object_list[ta].start,
+			       texture_memory_alloc::object_list[ta].end,
+			       opb_size[0].total(),
+			       ta_alloc,
+			       tile_width,
+			       tile_height);
+    transfer_scene(font, glyphs);
+  }
+
+  serial::string("return\n");
+}
diff --git a/unparse.c b/unparse.c
new file mode 100644
index 0000000..5fd4ec7
--- /dev/null
+++ b/unparse.c
@@ -0,0 +1,116 @@
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "minmax.h"
+
+static int digits_base10(uint32_t n)
+{
+  if (n >= 1000000000) return 10;
+  if (n >= 100000000) return 9;
+  if (n >= 10000000) return 8;
+  if (n >= 1000000) return 7;
+  if (n >= 100000) return 6;
+  if (n >= 10000) return 5;
+  if (n >= 1000) return 4;
+  if (n >= 100) return 3;
+  if (n >= 10) return 2;
+  return 1;
+}
+
+int unparse_base10(char * s, int32_t n, int len, char fill)
+{
+  bool negative = false;
+  int digits = 0;
+  if (n < 0) {
+    digits += 1;
+    n = -n;
+    negative = true;
+  }
+
+  digits += digits_base10(n);
+  len = max(digits, len);
+  int ret = len;
+
+  while (len > digits) {
+    *s++ = fill;
+    --len;
+  }
+
+  if (negative) {
+    *s++ = '-';
+    len--;
+  }
+
+  while (len > 0) {
+    const uint32_t digit = n % 10;
+    n = n / 10;
+    s[--len] = digit + 48;
+  }
+
+  return ret;
+}
+
+static int digits_base16(uint32_t n)
+{
+  if (n <= 0xf) return 1;
+  if (n <= 0xff) return 2;
+  if (n <= 0xfff) return 3;
+  if (n <= 0xffff) return 4;
+  if (n <= 0xfffff) return 5;
+  if (n <= 0xffffff) return 6;
+  if (n <= 0xfffffff) return 7;
+  return 8;
+}
+
+int unparse_base16(char * s, uint32_t n, int len, char fill)
+{
+  int digits = digits_base16(n);
+  len = max(digits, len);
+  int ret = len;
+
+  while (len > digits) {
+    *s++ = fill;
+    --len;
+  }
+
+  while (len > 0) {
+    uint32_t nib = n & 0xf;
+    n = n >> 4;
+    if (nib > 9) {
+      nib += (97 - 10);
+    } else {
+      nib += (48 - 0);
+    }
+
+    s[--len] = nib;
+  }
+
+  return ret;
+}
+
+#ifdef UNPARSE_TEST
+#include <stdio.h>
+
+int main()
+{
+  char s[1024];
+
+  {
+    int n = 124;
+
+    int offset = unparse_base10(s, n, 6, ' ');
+    s[offset] = 0;
+
+    printf("`%s`\n", s);
+  }
+
+  {
+    int n = 0x5678;
+
+    int offset = unparse_base16(s, n, 7, '0');
+    s[offset] = 0;
+
+    printf("`%s`\n", s);
+  }
+}
+#endif
diff --git a/unparse.h b/unparse.h
new file mode 100644
index 0000000..2df3d49
--- /dev/null
+++ b/unparse.h
@@ -0,0 +1,12 @@
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int unparse_base10(char * s, uint32_t n, int len, char fill);
+int unparse_base16(char * s, uint32_t n, int len, char fill);
+
+#ifdef __cplusplus
+}
+#endif