Function ImFontAtlasBuildRenderDefaultTexData

lib/imgui/imgui_draw.cpp:2249–2278

}

static void ImFontAtlasBuildRenderDefaultTexData(ImFontAtlas* atlas)
{
    IM_ASSERT(atlas->CustomRectIds[0] >= 0);
    IM_ASSERT(atlas->TexPixelsAlpha8 != NULL);
    ImFontAtlasCustomRect& r = atlas->CustomRects[atlas->CustomRectIds[0]];
    IM_ASSERT(r.ID == FONT_ATLAS_DEFAULT_TEX_DATA_ID);
    IM_ASSERT(r.IsPacked());

    const int w = atlas->TexWidth;
    if (!(atlas->Flags & ImFontAtlasFlags_NoMouseCursors))
    {
        // Render/copy pixels
        IM_ASSERT(r.Width == FONT_ATLAS_DEFAULT_TEX_DATA_W_HALF * 2 + 1 && r.Height == FONT_ATLAS_DEFAULT_TEX_DATA_H);
        for (int y = 0, n = 0; y < FONT_ATLAS_DEFAULT_TEX_DATA_H; y++)
            for (int x = 0; x < FONT_ATLAS_DEFAULT_TEX_DATA_W_HALF; x++, n++)
            {
                const int offset0 = (int)(r.X + x) + (int)(r.Y + y) * w;
                const int offset1 = offset0 + FONT_ATLAS_DEFAULT_TEX_DATA_W_HALF + 1;
                atlas->TexPixelsAlpha8[offset0] = FONT_ATLAS_DEFAULT_TEX_DATA_PIXELS[n] == '.' ? 0xFF : 0x00;
                atlas->TexPixelsAlpha8[offset1] = FONT_ATLAS_DEFAULT_TEX_DATA_PIXELS[n] == 'X' ? 0xFF : 0x00;
            }
    }
    else
    {
        IM_ASSERT(r.Width == 2 && r.Height == 2);
        const int offset = (int)(r.X) + (int)(r.Y) * w;
        atlas->TexPixelsAlpha8[offset] = atlas->TexPixelsAlpha8[offset + 1] = atlas->TexPixelsAlpha8[offset + w] = atlas->TexPixelsAlpha8[offset + w + 1] = 0xFF;
    }
    atlas->TexUvWhitePixel = ImVec2((r.X + 0.5f) * atlas->TexUvScale.x, (r.Y + 0.5f) * atlas->TexUvScale.y);
}

void ImFontAtlasBuildFinish(ImFontAtlas* atlas)
{