| // dear imgui |
| // (binary_to_compressed_c.cpp) |
| // Helper tool to turn a file into a C array, if you want to embed font data in your source code. |
| |
| // The data is first compressed with stb_compress() to reduce source code size, |
| // then encoded in Base85 to fit in a string so we can fit roughly 4 bytes of compressed data into 5 bytes of source code (suggested by @mmalex) |
| // (If we used 32-bit constants it would require take 11 bytes of source code to encode 4 bytes, and be endianness dependent) |
| // Note that even with compression, the output array is likely to be bigger than the binary file.. |
| // Load compressed TTF fonts with ImGui::GetIO().Fonts->AddFontFromMemoryCompressedTTF() |
| |
| // Build with, e.g: |
| // # cl.exe binary_to_compressed_c.cpp |
| // # g++ binary_to_compressed_c.cpp |
| // # clang++ binary_to_compressed_c.cpp |
| // You can also find a precompiled Windows binary in the binary/demo package available from https://github.com/ocornut/imgui |
| |
| // Usage: |
| // binary_to_compressed_c.exe [-base85] [-nocompress] <inputfile> <symbolname> |
| // Usage example: |
| // # binary_to_compressed_c.exe myfont.ttf MyFont > myfont.cpp |
| // # binary_to_compressed_c.exe -base85 myfont.ttf MyFont > myfont.cpp |
| |
| #define _CRT_SECURE_NO_WARNINGS |
| #include <stdio.h> |
| #include <string.h> |
| #include <stdlib.h> |
| #include <assert.h> |
| |
| // stb_compress* from stb.h - declaration |
| typedef unsigned int stb_uint; |
| typedef unsigned char stb_uchar; |
| stb_uint stb_compress(stb_uchar* out, stb_uchar* in, stb_uint len); |
| |
| static bool binary_to_compressed_c(const char* filename, const char* symbol, bool use_base85_encoding, bool use_compression); |
| |
| int main(int argc, char** argv) |
| { |
| if (argc < 3) |
| { |
| printf("Syntax: %s [-base85] [-nocompress] <inputfile> <symbolname>\n", argv[0]); |
| return 0; |
| } |
| |
| int argn = 1; |
| bool use_base85_encoding = false; |
| bool use_compression = true; |
| if (argv[argn][0] == '-') |
| { |
| if (strcmp(argv[argn], "-base85") == 0) { use_base85_encoding = true; argn++; } |
| else if (strcmp(argv[argn], "-nocompress") == 0) { use_compression = false; argn++; } |
| else |
| { |
| fprintf(stderr, "Unknown argument: '%s'\n", argv[argn]); |
| return 1; |
| } |
| } |
| |
| bool ret = binary_to_compressed_c(argv[argn], argv[argn + 1], use_base85_encoding, use_compression); |
| if (!ret) |
| fprintf(stderr, "Error opening or reading file: '%s'\n", argv[argn]); |
| return ret ? 0 : 1; |
| } |
| |
| char Encode85Byte(unsigned int x) |
| { |
| x = (x % 85) + 35; |
| return (x >= '\\') ? x + 1 : x; |
| } |
| |
| bool binary_to_compressed_c(const char* filename, const char* symbol, bool use_base85_encoding, bool use_compression) |
| { |
| // Read file |
| FILE* f = fopen(filename, "rb"); |
| if (!f) return false; |
| int data_sz; |
| if (fseek(f, 0, SEEK_END) || (data_sz = (int)ftell(f)) == -1 || fseek(f, 0, SEEK_SET)) { fclose(f); return false; } |
| char* data = new char[data_sz + 4]; |
| if (fread(data, 1, data_sz, f) != (size_t)data_sz) { fclose(f); delete[] data; return false; } |
| memset((void*)(((char*)data) + data_sz), 0, 4); |
| fclose(f); |
| |
| // Compress |
| int maxlen = data_sz + 512 + (data_sz >> 2) + sizeof(int); // total guess |
| char* compressed = use_compression ? new char[maxlen] : data; |
| int compressed_sz = use_compression ? stb_compress((stb_uchar*)compressed, (stb_uchar*)data, data_sz) : data_sz; |
| if (use_compression) |
| memset(compressed + compressed_sz, 0, maxlen - compressed_sz); |
| |
| // Output as Base85 encoded |
| FILE* out = stdout; |
| fprintf(out, "// File: '%s' (%d bytes)\n", filename, (int)data_sz); |
| fprintf(out, "// Exported using binary_to_compressed_c.cpp\n"); |
| const char* compressed_str = use_compression ? "compressed_" : ""; |
| if (use_base85_encoding) |
| { |
| fprintf(out, "static const char %s_%sdata_base85[%d+1] =\n \"", symbol, compressed_str, (int)((compressed_sz + 3) / 4)*5); |
| char prev_c = 0; |
| for (int src_i = 0; src_i < compressed_sz; src_i += 4) |
| { |
| // This is made a little more complicated by the fact that ??X sequences are interpreted as trigraphs by old C/C++ compilers. So we need to escape pairs of ??. |
| unsigned int d = *(unsigned int*)(compressed + src_i); |
| for (unsigned int n5 = 0; n5 < 5; n5++, d /= 85) |
| { |
| char c = Encode85Byte(d); |
| fprintf(out, (c == '?' && prev_c == '?') ? "\\%c" : "%c", c); |
| prev_c = c; |
| } |
| if ((src_i % 112) == 112 - 4) |
| fprintf(out, "\"\n \""); |
| } |
| fprintf(out, "\";\n\n"); |
| } |
| else |
| { |
| fprintf(out, "static const unsigned int %s_%ssize = %d;\n", symbol, compressed_str, (int)compressed_sz); |
| fprintf(out, "static const unsigned int %s_%sdata[%d/4] =\n{", symbol, compressed_str, (int)((compressed_sz + 3) / 4)*4); |
| int column = 0; |
| for (int i = 0; i < compressed_sz; i += 4) |
| { |
| unsigned int d = *(unsigned int*)(compressed + i); |
| if ((column++ % 12) == 0) |
| fprintf(out, "\n 0x%08x, ", d); |
| else |
| fprintf(out, "0x%08x, ", d); |
| } |
| fprintf(out, "\n};\n\n"); |
| } |
| |
| // Cleanup |
| delete[] data; |
| if (use_compression) |
| delete[] compressed; |
| return true; |
| } |
| |
| // stb_compress* from stb.h - definition |
| |
| //////////////////// compressor /////////////////////// |
| |
| static stb_uint stb_adler32(stb_uint adler32, stb_uchar *buffer, stb_uint buflen) |
| { |
| const unsigned long ADLER_MOD = 65521; |
| unsigned long s1 = adler32 & 0xffff, s2 = adler32 >> 16; |
| unsigned long blocklen, i; |
| |
| blocklen = buflen % 5552; |
| while (buflen) { |
| for (i=0; i + 7 < blocklen; i += 8) { |
| s1 += buffer[0], s2 += s1; |
| s1 += buffer[1], s2 += s1; |
| s1 += buffer[2], s2 += s1; |
| s1 += buffer[3], s2 += s1; |
| s1 += buffer[4], s2 += s1; |
| s1 += buffer[5], s2 += s1; |
| s1 += buffer[6], s2 += s1; |
| s1 += buffer[7], s2 += s1; |
| |
| buffer += 8; |
| } |
| |
| for (; i < blocklen; ++i) |
| s1 += *buffer++, s2 += s1; |
| |
| s1 %= ADLER_MOD, s2 %= ADLER_MOD; |
| buflen -= blocklen; |
| blocklen = 5552; |
| } |
| return (s2 << 16) + s1; |
| } |
| |
| static unsigned int stb_matchlen(stb_uchar *m1, stb_uchar *m2, stb_uint maxlen) |
| { |
| stb_uint i; |
| for (i=0; i < maxlen; ++i) |
| if (m1[i] != m2[i]) return i; |
| return i; |
| } |
| |
| // simple implementation that just takes the source data in a big block |
| |
| static stb_uchar *stb__out; |
| static FILE *stb__outfile; |
| static stb_uint stb__outbytes; |
| |
| static void stb__write(unsigned char v) |
| { |
| fputc(v, stb__outfile); |
| ++stb__outbytes; |
| } |
| |
| //#define stb_out(v) (stb__out ? *stb__out++ = (stb_uchar) (v) : stb__write((stb_uchar) (v))) |
| #define stb_out(v) do { if (stb__out) *stb__out++ = (stb_uchar) (v); else stb__write((stb_uchar) (v)); } while (0) |
| |
| static void stb_out2(stb_uint v) { stb_out(v >> 8); stb_out(v); } |
| static void stb_out3(stb_uint v) { stb_out(v >> 16); stb_out(v >> 8); stb_out(v); } |
| static void stb_out4(stb_uint v) { stb_out(v >> 24); stb_out(v >> 16); stb_out(v >> 8 ); stb_out(v); } |
| |
| static void outliterals(stb_uchar *in, int numlit) |
| { |
| while (numlit > 65536) { |
| outliterals(in,65536); |
| in += 65536; |
| numlit -= 65536; |
| } |
| |
| if (numlit == 0) ; |
| else if (numlit <= 32) stb_out (0x000020 + numlit-1); |
| else if (numlit <= 2048) stb_out2(0x000800 + numlit-1); |
| else /* numlit <= 65536) */ stb_out3(0x070000 + numlit-1); |
| |
| if (stb__out) { |
| memcpy(stb__out,in,numlit); |
| stb__out += numlit; |
| } else |
| fwrite(in, 1, numlit, stb__outfile); |
| } |
| |
| static int stb__window = 0x40000; // 256K |
| |
| static int stb_not_crap(int best, int dist) |
| { |
| return ((best > 2 && dist <= 0x00100) |
| || (best > 5 && dist <= 0x04000) |
| || (best > 7 && dist <= 0x80000)); |
| } |
| |
| static stb_uint stb__hashsize = 32768; |
| |
| // note that you can play with the hashing functions all you |
| // want without needing to change the decompressor |
| #define stb__hc(q,h,c) (((h) << 7) + ((h) >> 25) + q[c]) |
| #define stb__hc2(q,h,c,d) (((h) << 14) + ((h) >> 18) + (q[c] << 7) + q[d]) |
| #define stb__hc3(q,c,d,e) ((q[c] << 14) + (q[d] << 7) + q[e]) |
| |
| static unsigned int stb__running_adler; |
| |
| static int stb_compress_chunk(stb_uchar *history, |
| stb_uchar *start, |
| stb_uchar *end, |
| int length, |
| int *pending_literals, |
| stb_uchar **chash, |
| stb_uint mask) |
| { |
| (void)history; |
| int window = stb__window; |
| stb_uint match_max; |
| stb_uchar *lit_start = start - *pending_literals; |
| stb_uchar *q = start; |
| |
| #define STB__SCRAMBLE(h) (((h) + ((h) >> 16)) & mask) |
| |
| // stop short of the end so we don't scan off the end doing |
| // the hashing; this means we won't compress the last few bytes |
| // unless they were part of something longer |
| while (q < start+length && q+12 < end) { |
| int m; |
| stb_uint h1,h2,h3,h4, h; |
| stb_uchar *t; |
| int best = 2, dist=0; |
| |
| if (q+65536 > end) |
| match_max = end-q; |
| else |
| match_max = 65536; |
| |
| #define stb__nc(b,d) ((d) <= window && ((b) > 9 || stb_not_crap(b,d))) |
| |
| #define STB__TRY(t,p) /* avoid retrying a match we already tried */ \ |
| if (p ? dist != q-t : 1) \ |
| if ((m = stb_matchlen(t, q, match_max)) > best) \ |
| if (stb__nc(m,q-(t))) \ |
| best = m, dist = q - (t) |
| |
| // rather than search for all matches, only try 4 candidate locations, |
| // chosen based on 4 different hash functions of different lengths. |
| // this strategy is inspired by LZO; hashing is unrolled here using the |
| // 'hc' macro |
| h = stb__hc3(q,0, 1, 2); h1 = STB__SCRAMBLE(h); |
| t = chash[h1]; if (t) STB__TRY(t,0); |
| h = stb__hc2(q,h, 3, 4); h2 = STB__SCRAMBLE(h); |
| h = stb__hc2(q,h, 5, 6); t = chash[h2]; if (t) STB__TRY(t,1); |
| h = stb__hc2(q,h, 7, 8); h3 = STB__SCRAMBLE(h); |
| h = stb__hc2(q,h, 9,10); t = chash[h3]; if (t) STB__TRY(t,1); |
| h = stb__hc2(q,h,11,12); h4 = STB__SCRAMBLE(h); |
| t = chash[h4]; if (t) STB__TRY(t,1); |
| |
| // because we use a shared hash table, can only update it |
| // _after_ we've probed all of them |
| chash[h1] = chash[h2] = chash[h3] = chash[h4] = q; |
| |
| if (best > 2) |
| assert(dist > 0); |
| |
| // see if our best match qualifies |
| if (best < 3) { // fast path literals |
| ++q; |
| } else if (best > 2 && best <= 0x80 && dist <= 0x100) { |
| outliterals(lit_start, q-lit_start); lit_start = (q += best); |
| stb_out(0x80 + best-1); |
| stb_out(dist-1); |
| } else if (best > 5 && best <= 0x100 && dist <= 0x4000) { |
| outliterals(lit_start, q-lit_start); lit_start = (q += best); |
| stb_out2(0x4000 + dist-1); |
| stb_out(best-1); |
| } else if (best > 7 && best <= 0x100 && dist <= 0x80000) { |
| outliterals(lit_start, q-lit_start); lit_start = (q += best); |
| stb_out3(0x180000 + dist-1); |
| stb_out(best-1); |
| } else if (best > 8 && best <= 0x10000 && dist <= 0x80000) { |
| outliterals(lit_start, q-lit_start); lit_start = (q += best); |
| stb_out3(0x100000 + dist-1); |
| stb_out2(best-1); |
| } else if (best > 9 && dist <= 0x1000000) { |
| if (best > 65536) best = 65536; |
| outliterals(lit_start, q-lit_start); lit_start = (q += best); |
| if (best <= 0x100) { |
| stb_out(0x06); |
| stb_out3(dist-1); |
| stb_out(best-1); |
| } else { |
| stb_out(0x04); |
| stb_out3(dist-1); |
| stb_out2(best-1); |
| } |
| } else { // fallback literals if no match was a balanced tradeoff |
| ++q; |
| } |
| } |
| |
| // if we didn't get all the way, add the rest to literals |
| if (q-start < length) |
| q = start+length; |
| |
| // the literals are everything from lit_start to q |
| *pending_literals = (q - lit_start); |
| |
| stb__running_adler = stb_adler32(stb__running_adler, start, q - start); |
| return q - start; |
| } |
| |
| static int stb_compress_inner(stb_uchar *input, stb_uint length) |
| { |
| int literals = 0; |
| stb_uint len,i; |
| |
| stb_uchar **chash; |
| chash = (stb_uchar**) malloc(stb__hashsize * sizeof(stb_uchar*)); |
| if (chash == NULL) return 0; // failure |
| for (i=0; i < stb__hashsize; ++i) |
| chash[i] = NULL; |
| |
| // stream signature |
| stb_out(0x57); stb_out(0xbc); |
| stb_out2(0); |
| |
| stb_out4(0); // 64-bit length requires 32-bit leading 0 |
| stb_out4(length); |
| stb_out4(stb__window); |
| |
| stb__running_adler = 1; |
| |
| len = stb_compress_chunk(input, input, input+length, length, &literals, chash, stb__hashsize-1); |
| assert(len == length); |
| |
| outliterals(input+length - literals, literals); |
| |
| free(chash); |
| |
| stb_out2(0x05fa); // end opcode |
| |
| stb_out4(stb__running_adler); |
| |
| return 1; // success |
| } |
| |
| stb_uint stb_compress(stb_uchar *out, stb_uchar *input, stb_uint length) |
| { |
| stb__out = out; |
| stb__outfile = NULL; |
| |
| stb_compress_inner(input, length); |
| |
| return stb__out - out; |
| } |