Files
amethyst/source/iron/font.cpp
tobid7 88e367a299 Implement Text Rendering
Added STB truetype
Switched AssetMgr to use Shared Ptr
2025-12-07 23:20:15 +01:00

269 lines
7.2 KiB
C++

#include <amethyst/iron.hpp>
#include <amethyst/utils.hpp>
#include <filesystem>
#if AMY_STB_TT == 1
#define STB_TRUETYPE_IMPLEMENTATION
#endif
#include <stb_truetype.h>
namespace Amy {
void Iron::Font::LoadBMF(ksr path) {}
void Iron::Font::LoadTTF(ksr path, int size) {
auto data = Amy::Utils::LoadFile2Mem(path);
LoadTTF(data, size);
}
void Iron::Font::LoadTTF(const vec<uc> &data, int size) {
/**
* Some additional Info:
* Removed the stbtt get bitmapbox as we dont need to place
* the glyps nicely in the tex. next step would be using the free
* space on the y axis to get mor glyphs inside
*/
PxHeight = size;
int texszs = Amy::Utils::NextPow2(PxHeight * 16);
if (texszs > 1024) {
texszs = 1024; // Max size
}
stbtt_fontinfo inf;
if (!stbtt_InitFont(&inf, data.data(), 0)) {
return;
}
float scale = stbtt_ScaleForPixelHeight(&inf, PxHeight);
int ascent, descent, lineGap;
stbtt_GetFontVMetrics(&inf, &ascent, &descent, &lineGap);
int baseline = static_cast<int>(ascent * scale);
// Cache to not render same codepoint tex twice
std::map<u32, int> buf_cache;
std::vector<u8> font_tex(texszs * texszs * 4, 0);
auto tex = Texture::New();
fvec2 off;
bool empty = true;
for (u32 ii = 0x0000; ii <= 0xFFFF; ii++) {
int gi = stbtt_FindGlyphIndex(&inf, ii);
if (gi == 0) continue;
if (stbtt_IsGlyphEmpty(&inf, gi)) continue;
int w = 0, h = 0, xo = 0, yo = 0;
unsigned char *bitmap =
stbtt_GetCodepointBitmap(&inf, scale, scale, ii, &w, &h, &xo, &yo);
if (!bitmap || w <= 0 || h <= 0) {
if (bitmap) free(bitmap);
continue;
}
u32 hashed_map =
Utils::HashMemory(std::vector<u8>(bitmap, bitmap + (w * h)));
if (buf_cache.find(hashed_map) != buf_cache.end()) {
Codepoint c = GetCodepoint(buf_cache[hashed_map]);
c.Cp = ii;
pCodeMap[ii] = c;
free(bitmap);
continue;
} else {
buf_cache[hashed_map] = ii;
}
// Next row
if (off.x + w > texszs) {
off.y += PxHeight;
off.x = 0.0f;
}
// Bake cause we go out of the tex
if (off.y + PxHeight > texszs) {
pMakeAtlas(false, font_tex, texszs, tex);
tex = Texture::New();
off = 0;
std::fill(font_tex.begin(), font_tex.end(), 0);
empty = true;
}
// UVs & Codepoint
Codepoint c;
fvec4 uvs;
// cast the ints to floats and not the floats...
// dont know where my mind was when creating the code
uvs.x = off.x / static_cast<float>(texszs);
uvs.y = off.y / static_cast<float>(texszs);
uvs.z = (off.x + w) / static_cast<float>(texszs);
uvs.w = (off.y + h) / static_cast<float>(texszs);
// Flip (too lazy to place it into the seq at top)
uvs.y = 1.f - uvs.y;
uvs.w = 1.f - uvs.w;
c.Uv = uvs;
c.Tex = tex;
c.Size = fvec2(w, h);
c.Offset = baseline + yo;
c.Cp = ii;
for (int y = 0; y < h; ++y) {
for (int x = 0; x < w; ++x) {
int map_pos = ((static_cast<int>(off.y) + y) * texszs +
(static_cast<int>(off.x) + x)) *
4;
font_tex[map_pos + 0] = 255;
font_tex[map_pos + 1] = 255;
font_tex[map_pos + 2] = 255;
font_tex[map_pos + 3] = bitmap[x + y * w];
}
}
empty = false;
pCodeMap[ii] = c;
free(bitmap);
// offset by 1 (prevents visual glitches i had)
off.x += w + 1;
}
if (!empty) {
pMakeAtlas(true, font_tex, texszs, tex);
}
}
void Iron::Font::pMakeAtlas(bool final, vec<uc> &font_tex, int texszs,
Texture::Ref tex) {
tex->Load(font_tex, texszs, texszs);
Textures.push_back(tex);
}
Iron::Font::Codepoint &Iron::Font::GetCodepoint(ui cp) {
// Check if codepoijt exist or return a static invalid one
auto res = pCodeMap.find(cp);
if (res == pCodeMap.end()) {
static Codepoint invalid;
invalid.Valid = false;
return invalid;
}
return res->second;
}
fvec2 Iron::Font::GetTextBounds(ksr text, float scale) {
// Use wstring for exemple for german äöü
auto wtext = std::filesystem::path(text).wstring();
// Create a temp position and offset as [0, 0]
fvec2 res;
float x = 0;
// Curent Font Scale
float cfs = (PxFactor * scale) / (float)PxHeight;
float lh = (float)PxHeight * cfs;
size_t index = 0;
for (auto &it : wtext) {
if (it == L'\0') {
break;
}
index++;
auto cp = GetCodepoint(it);
if (!cp.Valid && it != '\n' && it != '\t' && it != ' ') {
continue;
}
switch (it) {
case L'\n':
res.y += lh;
res.x = std::max(res.x, x);
x = 0.f;
break;
case L'\t':
x += 16 * cfs;
break;
case L' ':
x += 4 * cfs;
// Fall trough here to get the same result as in
// TextCommand if/else Section
default:
x += cp.Size.x * cfs;
if (index != wtext.size()) {
x += 2 * cfs;
}
break;
}
}
res.x = std::max(res.x, x);
res.y += lh;
return res;
}
void Iron::Font::CmdTextEx(vec<Command::Ref> &cmds, const fvec2 &pos, ui color,
float scale, const std::string &text,
AmyTextFlags flags, const fvec2 &box) {
fvec2 off;
float cfs = (PxFactor * scale) / (float)PxHeight;
float lh = (float)PxHeight * cfs;
fvec2 td;
fvec2 rpos = pos;
fvec2 rbox = box;
if (flags & (AmyTextFlags_AlignMid | AmyTextFlags_AlignRight)) {
td = GetTextBounds(text, scale);
}
if (flags & AmyTextFlags_AlignMid) {
rpos = rbox * 0.5 - td * 0.5 + pos;
}
if (flags & AmyTextFlags_AlignRight) {
rpos.x = rpos.x - td.x;
}
std::vector<std::string> lines;
std::istringstream iss(text);
std::string tmp;
while (std::getline(iss, tmp)) {
lines.push_back(tmp);
}
for (auto &it : lines) {
/*if (flags & AmyTextFlags_Short) {
fvec2 tmp_dim;
it = ShortText(it, box.x() - pos.x(), tmp_dim);
}*/
// Bitte nicht nachmachen... Also ernsthaft jz, bitte macht das nicht
auto wline = std::filesystem::path(it).wstring();
auto cmd = Command::New();
auto Tex = GetCodepoint(wline[0]).Tex;
cmd->Tex = Tex;
for (auto &jt : wline) {
auto cp = GetCodepoint(jt);
if ((!cp.Valid && jt != L' ' && jt != L'\n' && jt != L'\t') &&
jt != L'\r') {
continue;
}
if (Tex != cp.Tex) {
cmds.push_back(std::move(cmd));
cmd = Command::New();
Tex = cp.Tex;
cmd->Tex = Tex;
}
if (jt == L'\t') {
off.x += 16 * cfs;
} else {
if (jt != L' ') {
if (flags & AmyTextFlags_Shaddow) {
// Draw
Rect rec = Iron::PrimRect(
rpos + vec2(off.x + 1, off.y + (cp.Offset * cfs)) + 1,
cp.Size * cfs, 0.f);
Iron::CmdQuad(cmd.get(), rec, cp.Uv, 0xff111111);
}
// Draw
Rect rec = Iron::PrimRect(rpos + off + fvec2(0, (cp.Offset * cfs)),
cp.Size * cfs, 0.f);
Iron::CmdQuad(cmd.get(), rec, cp.Uv, color);
off.x += cp.Size.x * cfs + 2 * cfs;
} else {
off.x += 4 * cfs;
}
}
}
cmds.push_back(std::move(cmd));
off.y += lh;
off.x = 0;
}
}
} // namespace Amy