IPlug2 NvgText

IPlugEffect.cpp

#include "IPlugEffect.h"
#include "IPlug_include_in_plug_src.h"
#include "IControls.h"

class NVGTextDemo : public IControl {
public:
  float mMouseX, mMouseY;
  NVGTextDemo(const IRECT& bounds)
  : IControl(bounds, kNoParameter) {}
  
  void Draw(IGraphics& g) override
  {
    NVGcontext* ctx = (NVGcontext*) g.GetDrawContext();
    drawParagraph(ctx, mRECT.L, mRECT.T, mRECT.W(), mRECT.H(), mMouseX, mMouseY);
  }
  
  void OnMouseOver(float x, float y, const IMouseMod &mod) override
  {
    mMouseX = x;
    mMouseY = y;
    SetDirty(false);
  }
  
  void drawParagraph(NVGcontext* vg, float x, float y, float width, float height, float mx, float my)
  {
    NVGtextRow rows[3];
    NVGglyphPosition glyphs[100];
    const char* text = "This is longer chunk of text.\n  \n  Would have used lorem ipsum but she    was busy jumping over the lazy dog with the fox and all the men who came to the aid of the party.🎉";
    const char* start;
    const char* end;
    int nrows, i, nglyphs, j, lnum = 0;
    float lineh;
    float caretx, px;
    float bounds[4];
    float a;
    float gx,gy;
    int gutter = 0;
    NVG_NOTUSED(height);

    nvgSave(vg);

    nvgFontSize(vg, 18.0f);
    nvgFontFace(vg, "Roboto-Regular");
    nvgTextAlign(vg, NVG_ALIGN_LEFT|NVG_ALIGN_TOP);
    nvgTextMetrics(vg, NULL, NULL, &lineh);

    // The text break API can be used to fill a large buffer of rows,
    // or to iterate over the text just few lines (or just one) at a time.
    // The "next" variable of the last returned item tells where to continue.
    start = text;
    end = text + strlen(text);
    while ((nrows = nvgTextBreakLines(vg, start, end, width, rows, 3))) {
      for (i = 0; i < nrows; i++) {
        NVGtextRow* row = &rows[i];
        int hit = mx > x && mx < (x+width) && my >= y && my < (y+lineh);

        nvgBeginPath(vg);
        nvgFillColor(vg, nvgRGBA(255,255,255,hit?64:16));
        nvgRect(vg, x, y, row->width, lineh);
        nvgFill(vg);

        nvgFillColor(vg, nvgRGBA(255,255,255,255));
        nvgText(vg, x, y, row->start, row->end);

        if (hit) {
          caretx = (mx < x+row->width/2) ? x : x+row->width;
          px = x;
          nglyphs = nvgTextGlyphPositions(vg, x, y, row->start, row->end, glyphs, 100);
          for (j = 0; j < nglyphs; j++) {
            float x0 = glyphs[j].x;
            float x1 = (j+1 < nglyphs) ? glyphs[j+1].x : x+row->width;
            float gx = x0 * 0.3f + x1 * 0.7f;
            if (mx >= px && mx < gx)
              caretx = glyphs[j].x;
            px = gx;
          }
          nvgBeginPath(vg);
          nvgFillColor(vg, nvgRGBA(255,192,0,255));
          nvgRect(vg, caretx, y, 1, lineh);
          nvgFill(vg);

          gutter = lnum+1;
          gx = x - 10;
          gy = y + lineh/2;
        }
        lnum++;
        y += lineh;
      }
      // Keep going...
      start = rows[nrows-1].next;
    }

    if (gutter) {
      char txt[16];
      snprintf(txt, sizeof(txt), "%d", gutter);
      nvgFontSize(vg, 13.0f);
      nvgTextAlign(vg, NVG_ALIGN_RIGHT|NVG_ALIGN_MIDDLE);

      nvgTextBounds(vg, gx,gy, txt, NULL, bounds);

      nvgBeginPath(vg);
      nvgFillColor(vg, nvgRGBA(255,192,0,255));
      nvgRoundedRect(vg, (int)bounds[0]-4,(int)bounds[1]-2, (int)(bounds[2]-bounds[0])+8, (int)(bounds[3]-bounds[1])+4, ((int)(bounds[3]-bounds[1])+4)/2-1);
      nvgFill(vg);

      nvgFillColor(vg, nvgRGBA(32,32,32,255));
      nvgText(vg, gx,gy, txt, NULL);
    }

    y += 20.0f;

    nvgFontSize(vg, 13.0f);
    nvgTextAlign(vg, NVG_ALIGN_LEFT|NVG_ALIGN_TOP);
    nvgTextLineHeight(vg, 1.2f);

    nvgTextBoxBounds(vg, x,y, 150, "Hover your mouse over the text to see calculated caret position.", NULL, bounds);

    // Fade the tooltip out when close to it.
    gx = fabsf((mx - (bounds[0]+bounds[2])*0.5f) / (bounds[0] - bounds[2]));
    gy = fabsf((my - (bounds[1]+bounds[3])*0.5f) / (bounds[1] - bounds[3]));
    a = std::fmaxf(gx, gy) - 0.5f;
    a = Clip(a, 0.f, 1.f);
    nvgGlobalAlpha(vg, a);

    nvgBeginPath(vg);
    nvgFillColor(vg, nvgRGBA(220,220,220,255));
    nvgRoundedRect(vg, bounds[0]-2,bounds[1]-2, (int)(bounds[2]-bounds[0])+4, (int)(bounds[3]-bounds[1])+4, 3);
    px = (int)((bounds[2]+bounds[0])/2);
    nvgMoveTo(vg, px,bounds[1] - 10);
    nvgLineTo(vg, px+7,bounds[1]+1);
    nvgLineTo(vg, px-7,bounds[1]+1);
    nvgFill(vg);

    nvgFillColor(vg, nvgRGBA(0,0,0,220));
    nvgTextBox(vg, x,y, 150, "Hover your mouse over the text to see calculated caret position.", NULL);

    nvgRestore(vg);
  }
};

IPlugEffect::IPlugEffect(const InstanceInfo& info)
: Plugin(info, MakeConfig(kNumParams, kNumPresets))
{
  GetParam(kGain)->InitDouble("Gain", 0., 0., 100.0, 0.01, "%");

  mMakeGraphicsFunc = [&]() {
    return MakeGraphics(*this, PLUG_WIDTH, PLUG_HEIGHT, PLUG_FPS, GetScaleForScreen(PLUG_HEIGHT));
  };
  
  mLayoutFunc = [&](IGraphics* pGraphics) {
    pGraphics->AttachCornerResizer(EUIResizerMode::Scale, false);
    pGraphics->AttachPanelBackground(COLOR_GRAY);
    pGraphics->LoadFont("Roboto-Regular", ROBOTO_FN);
    pGraphics->EnableMouseOver(true);
    const IRECT b = pGraphics->GetBounds();
    pGraphics->AttachControl(new NVGTextDemo(b.GetCentredInside(300, 300)));
  };
}

#if IPLUG_DSP
void IPlugEffect::ProcessBlock(sample** inputs, sample** outputs, int nFrames)
{
  const double gain = GetParam(kGain)->Value() / 100.;
  const int nChans = NOutChansConnected();
  
  for (int s = 0; s < nFrames; s++) {
    for (int c = 0; c < nChans; c++) {
      outputs[c][s] = inputs[c][s] * gain;
    }
  }
}
#endif