Example #1
0
	void RenderText(GLfloat x, GLfloat y, const oglplus::String& text)
	{
		using namespace oglplus;

		glyph_spacings.resize(text.size()+1);
		text_glyphs.GetSpacing(
			PathNVListMode::AccumAdjacentPairs,
			text,
			1.0f, 1.0f,
			PathNVTransformType::TranslateX,
			glyph_spacings
		);
		glyph_spacings.insert(glyph_spacings.begin(), 0);

		dsa.ModelviewMatrix()
			.LoadIdentity()
			.Translate(x, y, 0);

		text_glyphs.StencilFillInstanced(
			text,
			PathNVFillMode::CountUp,
			0xFF,
			PathNVTransformType::TranslateX,
			glyph_spacings
		);
		text_glyphs.CoverFillInstanced(
			text,
			PathNVFillCoverMode::BoundingBoxOfBoundingBoxes,
			PathNVTransformType::TranslateX,
			glyph_spacings
		);
	}
    TextExample(int /*argc*/, const char** /*argv*/)
      : text("OpenGL")
      , text_path(text.size())
      , glyph_indices(make_glyph_indices())
      , glyph_spacings(glyph_indices.size()) {
        using namespace oglplus;

        GLfloat font_scale = 64;

        text_path.Glyphs(
          PathNVFontTarget::Standard,
          "Sans",
          PathNVFontStyle::Bold,
          text,
          PathNVMissingGlyph::Use,
          ~0,
          font_scale);

        text_path.GetSpacing(
          PathNVListMode::AccumAdjacentPairs,
          glyph_indices,
          1.0f,
          1.0f,
          PathNVTransformType::TranslateX,
          glyph_spacings);

        glyph_spacings.insert(glyph_spacings.begin(), 0);
        glyph_spacings.pop_back();
        glyph_indices.pop_back();

        GLfloat text_left = glyph_spacings.front();
        GLfloat text_right = glyph_spacings.back();

        GLfloat font_min_max[2];

        text_path.GetMetricRange(
          PathNVMetricQuery::FontYMinBounds | PathNVMetricQuery::FontYMaxBounds,
          1,
          0,
          font_min_max);

        projection.Ortho(
          text_left - 10,
          text_right + 10,
          font_min_max[0],
          font_min_max[1],
          -1.0,
          +1.0);
        modelview.LoadIdentity();

        gl.ClearColor(1.0f, 1.0f, 1.0f, 0.0f);
        gl.ClearStencil(0);
        gl.StencilMask(~0);
        gl.StencilFunc(CompareFunction::NotEqual, 0, 0xFF);
        gl.StencilOp(
          StencilOperation::Keep,
          StencilOperation::Keep,
          StencilOperation::Zero);

        gl.Enable(Capability::StencilTest);
    }