hhmacos

asset_builder.cpp

stbtt_fontinfo Font;
stbtt_InitFont(&Font, (u8 *)TTFFile.Contents, stbtt_GetFontOffsetForIndex((u8 *)TTFFile.Contents, 0));

int Width, Height, XOffset, YOffset;
r32 Scale = stbtt_ScaleForPixelHeight(&Font, 128.0f); // 64.0f
u8 *MonoBitmap = stbtt_GetCodepointBitmap(&Font, 0, Scale, Codepoint,
                                          &Width, &Height, &XOffset, &YOffset);

int Ascent, Descent, LineGap;
stbtt_GetFontVMetrics(&Font, &Ascent, &Descent, &LineGap);

int X0, X1, Y0, Y1;
stbtt_GetCodepointBox(&Font, Codepoint, &X0, &Y0, &X1, &Y1);

r32 TotalHeight = ((Ascent - Descent + LineGap) * Scale);
r32 MaxY = (Ascent * Scale - Y0 * Scale);

Result.Width = Width + 1;
Result.Height = Height + 1;
Result.Pitch = Result.Width * BITMAP_BYTES_PER_PIXEL;
Result.Memory = malloc(Result.Height * Result.Pitch);
Result.Free = Result.Memory;

u8 *DestRow = (u8 *) Result.Memory + (Height - 1) * Result.Pitch;
u8 *Source = MonoBitmap;

for(s32 Y = 0;
    Y < Height;
    ++Y)
{
    u32 *Dest = (u32 *) DestRow;

    for(s32 X = 0;
        X < Width;
        ++X)
    {
        u32 Pixel = *Source;
        r32 Gray = (r32)(Pixel & 0xFF);
        v4 Texel = {255.0f, 255.0f, 255.0f, Gray};

        Texel = SRGB255ToLinear1(Texel);
        Texel.rgb *= Texel.a;
        Texel = Linear1ToSRGB255(Texel);

        *Dest++ = (((uint32)(Texel.a + 0.5f) << 24) |
                   ((uint32)(Texel.r + 0.5f) << 16) |
                   ((uint32)(Texel.g + 0.5f) << 8) |
                   ((uint32)(Texel.b + 0.5f) << 0));

        ++Source;
    }

    DestRow -= Result.Pitch;
}

stbtt_FreeBitmap(MonoBitmap, 0);
free(TTFFile.Contents);

Asset->Bitmap.AlignPercentage[0] = 1.0f / (r32) Result.Width;
Asset->Bitmap.AlignPercentage[1] = (1.0f + MaxY - (TotalHeight + Descent*Scale)) / (r32) Result.Height;