Function AddTextVertical

Source/3rdParty/implot/implot.cpp:378–424

//-----------------------------------------------------------------------------

void AddTextVertical(ImDrawList *DrawList, ImVec2 pos, ImU32 col, const char *text_begin, const char* text_end) {
    // the code below is based loosely on ImFont::RenderText
    if (!text_end)
        text_end = text_begin + strlen(text_begin);
    ImGuiContext& g = *GImGui;
#ifdef IMGUI_HAS_TEXTURES
    ImFontBaked* font = g.Font->GetFontBaked(g.FontSize);
    const float scale = g.FontSize / font->Size;
#else
    ImFont* font = g.Font;
    const float scale = g.FontSize / font->FontSize;
#endif
    // Align to be pixel perfect
    pos.x = ImFloor(pos.x);
    pos.y = ImFloor(pos.y);
    const char* s = text_begin;
    int chars_exp = (int)(text_end - s);
    int chars_rnd = 0;
    const int vtx_count_max = chars_exp * 4;
    const int idx_count_max = chars_exp * 6;
    DrawList->PrimReserve(idx_count_max, vtx_count_max);
    while (s < text_end) {
        unsigned int c = (unsigned int)*s;
        if (c < 0x80) {
            s += 1;
        }
        else {
            s += ImTextCharFromUtf8(&c, s, text_end);
            if (c == 0) // Malformed UTF-8?
                break;
        }
        const ImFontGlyph * glyph = font->FindGlyph((ImWchar)c);
        if (glyph == nullptr) {
            continue;
        }
        DrawList->PrimQuadUV(pos + ImVec2(glyph->Y0, -glyph->X0) * scale, pos + ImVec2(glyph->Y0, -glyph->X1) * scale,
                             pos + ImVec2(glyph->Y1, -glyph->X1) * scale, pos + ImVec2(glyph->Y1, -glyph->X0) * scale,
                             ImVec2(glyph->U0, glyph->V0), ImVec2(glyph->U1, glyph->V0),
                             ImVec2(glyph->U1, glyph->V1), ImVec2(glyph->U0, glyph->V1),
                             col);
        pos.y -= glyph->AdvanceX * scale;
        chars_rnd++;
    }
    // Give back unused vertices
    int chars_skp = chars_exp-chars_rnd;
    DrawList->PrimUnreserve(chars_skp*6, chars_skp*4);
}

void AddTextCentered(ImDrawList* DrawList, ImVec2 top_center, ImU32 col, const char* text_begin, const char* text_end) {
    float txt_ht = ImGui::GetTextLineHeight();