C++ rasterizer_scanline_aa::line_to_d方法代码示例

    virtual void on_draw()
    {
        pixfmt            pixf(rbuf_window());
        pixfmt_pre        pixf_pre(rbuf_window());
        renderer_base     rb(pixf);
        renderer_base_pre rb_pre(pixf_pre);

        if(!m_test_flag)
        {
            rb.clear(agg::rgba(1, 1, 1));
        }

        if(m_trans_type.cur_item() == 0)
        {
            // For the affine parallelogram transformations we
            // calculate the 4-th (implicit) point of the parallelogram
            m_quad.xn(3) = m_quad.xn(0) + (m_quad.xn(2) - m_quad.xn(1));
            m_quad.yn(3) = m_quad.yn(0) + (m_quad.yn(2) - m_quad.yn(1));
        }

        if(!m_test_flag)
        {
            //--------------------------
            // Render the "quad" tool and controls
            g_rasterizer.add_path(m_quad);
            agg::render_scanlines_aa_solid(g_rasterizer, g_scanline, rb, agg::rgba(0, 0.3, 0.5, 0.6));

            //--------------------------
            agg::render_ctrl(g_rasterizer, g_scanline, rb, m_trans_type);
        }

        // Prepare the polygon to rasterize. Here we need to fill
        // the destination (transformed) polygon.
        g_rasterizer.clip_box(0, 0, width(), height());
        g_rasterizer.reset();
        g_rasterizer.move_to_d(m_quad.xn(0), m_quad.yn(0));
        g_rasterizer.line_to_d(m_quad.xn(1), m_quad.yn(1));
        g_rasterizer.line_to_d(m_quad.xn(2), m_quad.yn(2));
        g_rasterizer.line_to_d(m_quad.xn(3), m_quad.yn(3));


        typedef agg::span_allocator<color_type> span_alloc_type;
        span_alloc_type sa;
        agg::image_filter<agg::image_filter_hanning> filter;
    
        typedef agg::wrap_mode_reflect_auto_pow2 remainder_type;
        typedef agg::image_accessor_wrap<pixfmt, 
                                         remainder_type, 
                                         remainder_type> img_source_type;

        pixfmt img_pixf(rbuf_img(0));
        img_source_type img_src(img_pixf);

        enum subdiv_shift_e { subdiv_shift = 2 };
         
        switch(m_trans_type.cur_item())
        {
            case 0:
            {
                // Note that we consruct an affine matrix that transforms
                // a parallelogram to a rectangle, i.e., it's inverted.
                // It's actually the same as:
                // tr(g_x1, g_y1, g_x2, g_y2, m_triangle.polygon());
                // tr.invert();
                agg::trans_affine tr(m_quad.polygon(), g_x1, g_y1, g_x2, g_y2);

                // Also note that we can use the linear interpolator instead of 
                // arbitrary span_interpolator_trans. It works much faster, 
                // but the transformations must be linear and parellel.
                typedef agg::span_interpolator_linear<agg::trans_affine> interpolator_type;
                interpolator_type interpolator(tr);

                typedef span_image_filter_2x2<img_source_type,
                                              interpolator_type> span_gen_type;
                span_gen_type sg(img_src, interpolator, filter);
                agg::render_scanlines_aa(g_rasterizer, g_scanline, rb_pre, sa, sg);
                break;
            }

            case 1:
            {
                agg::trans_bilinear tr(m_quad.polygon(), g_x1, g_y1, g_x2, g_y2);
                if(tr.is_valid())
                {
                    typedef agg::span_interpolator_linear<agg::trans_bilinear> interpolator_type;
                    interpolator_type interpolator(tr);

                    typedef span_image_filter_2x2<img_source_type,
                                                  interpolator_type> span_gen_type;
                    span_gen_type sg(img_src, interpolator, filter);
                    agg::render_scanlines_aa(g_rasterizer, g_scanline, rb_pre, sa, sg);
                }
                break;
            }

            case 2:
            {
                agg::trans_perspective tr(m_quad.polygon(), g_x1, g_y1, g_x2, g_y2);
                if(tr.is_valid())
                {
//.........这里部分代码省略.........

    virtual void on_draw()
    {
        pixfmt pixf(rbuf_window());
        renderer_base rb(pixf);
        renderer_solid rs(rb);
        rb.clear(agg::rgba(1, 1, 1));

        // When Gamma changes rebuild the gamma and gradient LUTs 
        //------------------
        if(m_old_gamma != m_gamma.value())
        {
            m_gamma_lut.gamma(m_gamma.value());
            build_gradient_lut();
            m_old_gamma = m_gamma.value();
        }


        // Gradient center. All gradient functions assume the 
        // center being in the origin (0,0) and you can't 
        // change it. But you can apply arbitrary transformations
        // to the gradient (see below).
        //------------------
        double cx = initial_width()  / 2;
        double cy = initial_height() / 2;
        double r = 100;

        // Focal center. Defined in the gradient coordinates, 
        // that is, with respect to the origin (0,0)
        //------------------
        double fx = m_mouse_x - cx;
        double fy = m_mouse_y - cy;

        gradient_func_type    gradient_func(r, fx, fy);
        gradient_adaptor_type gradient_adaptor(gradient_func);
        agg::trans_affine     gradient_mtx;
        
        // Making the affine matrix. Move to (cx,cy), 
        // apply the resizing transformations and invert
        // the matrix. Gradients and images always assume the
        // inverse transformations.
        //------------------
        gradient_mtx.translate(cx, cy);
        gradient_mtx *= trans_affine_resizing();
        gradient_mtx.invert();

        interpolator_type     span_interpolator(gradient_mtx);
        span_gradient_type    span_gradient(span_interpolator, 
                                          gradient_adaptor, 
                                          m_gradient_lut, 
                                          0, r);

        // Form the simple rectangle 
        //------------------
        m_rasterizer.reset();
        m_rasterizer.move_to_d(0,0);
        m_rasterizer.line_to_d(width(), 0);
        m_rasterizer.line_to_d(width(), height());
        m_rasterizer.line_to_d(0, height());

        // Render the gradient to the whole screen and measure the time
        //------------------
        start_timer();
        agg::render_scanlines_aa(m_rasterizer, m_scanline, rb, m_alloc, span_gradient);
        double tm = elapsed_time();

        // Draw the transformed circle that shows the gradient boundary
        //------------------
        agg::ellipse e(cx, cy, r, r);
        agg::conv_stroke<agg::ellipse> estr(e);
        agg::conv_transform<
            agg::conv_stroke<
                agg::ellipse> > etrans(estr, trans_affine_resizing());

        m_rasterizer.add_path(etrans);
        agg::render_scanlines_aa_solid(m_rasterizer, m_scanline, rb, agg::rgba(1,1,1));

        // Show the gradient time
        //------------------
        char buf[64]; 
        agg::gsv_text t;
        t.size(10.0);
        agg::conv_stroke<agg::gsv_text> pt(t);
        pt.width(1.5);
        sprintf(buf, "%3.2f ms", tm);
        t.start_point(10.0, 35.0);
        t.text(buf);
        m_rasterizer.add_path(pt);
        agg::render_scanlines_aa_solid(m_rasterizer, m_scanline, rb, agg::rgba(0,0,0));

#if !LINEAR_RGB
        // Show the controls
        //------------------
        agg::render_ctrl(m_rasterizer, m_scanline, rb, m_gamma);

        // Apply the inverse gamma to the whole buffer 
        // (transform the colors to the perceptually uniform space)
        //------------------
        pixf.apply_gamma_inv(m_gamma_lut);
#endif
    }

    virtual void on_draw()
    {
        if(m_gamma.value() != m_old_gamma)
        {
            m_gamma_lut.gamma(m_gamma.value());
            load_img(0, "spheres");
            pixfmt pixf(rbuf_img(0));
            pixf.apply_gamma_dir(m_gamma_lut);
            m_old_gamma = m_gamma.value();
        }

        pixfmt            pixf(rbuf_window());
        pixfmt_pre        pixf_pre(rbuf_window());
        renderer_base     rb(pixf);
        renderer_base_pre rb_pre(pixf_pre);

        renderer_solid r(rb);

        rb.clear(agg::rgba(1, 1, 1));

        if(m_trans_type.cur_item() < 2)
        {
            // For the affine parallelogram transformations we
            // calculate the 4-th (implicit) point of the parallelogram
            m_quad.xn(3) = m_quad.xn(0) + (m_quad.xn(2) - m_quad.xn(1));
            m_quad.yn(3) = m_quad.yn(0) + (m_quad.yn(2) - m_quad.yn(1));
        }

        //--------------------------
        // Render the "quad" tool and controls
        g_rasterizer.add_path(m_quad);
        r.color(agg::rgba(0, 0.3, 0.5, 0.1));
        agg::render_scanlines(g_rasterizer, g_scanline, r);

        // Prepare the polygon to rasterize. Here we need to fill
        // the destination (transformed) polygon.
        g_rasterizer.clip_box(0, 0, width(), height());
        g_rasterizer.reset();
        int b = 0;
        g_rasterizer.move_to_d(m_quad.xn(0)-b, m_quad.yn(0)-b);
        g_rasterizer.line_to_d(m_quad.xn(1)+b, m_quad.yn(1)-b);
        g_rasterizer.line_to_d(m_quad.xn(2)+b, m_quad.yn(2)+b);
        g_rasterizer.line_to_d(m_quad.xn(3)-b, m_quad.yn(3)+b);

        typedef agg::span_allocator<color_type> span_alloc_type;
        span_alloc_type sa;
        agg::image_filter_bilinear filter_kernel;
        agg::image_filter_lut filter(filter_kernel, true);

        pixfmt pixf_img(rbuf_img(0));
        typedef agg::image_accessor_clone<pixfmt> source_type;
        source_type source(pixf_img);

        start_timer();
        switch(m_trans_type.cur_item())
        {
            case 0:
            {
                agg::trans_affine tr(m_quad.polygon(), g_x1, g_y1, g_x2, g_y2);

                typedef agg::span_interpolator_linear<agg::trans_affine> interpolator_type;
                interpolator_type interpolator(tr);

                typedef image_filter_2x2_type<source_type, 
                                              interpolator_type> span_gen_type;
                span_gen_type sg(source, interpolator, filter);
                agg::render_scanlines_aa(g_rasterizer, g_scanline, rb_pre, sa, sg);
                break;
            }

            case 1:
            {
                agg::trans_affine tr(m_quad.polygon(), g_x1, g_y1, g_x2, g_y2);

                typedef agg::span_interpolator_linear<agg::trans_affine> interpolator_type;
                typedef image_resample_affine_type<source_type> span_gen_type;

                interpolator_type interpolator(tr);
                span_gen_type sg(source, interpolator, filter);
                sg.blur(m_blur.value());
                agg::render_scanlines_aa(g_rasterizer, g_scanline, rb_pre, sa, sg);
                break;
            }

            case 2:
            {
                agg::trans_perspective tr(m_quad.polygon(), g_x1, g_y1, g_x2, g_y2);
                if(tr.is_valid())
                {
                    typedef agg::span_interpolator_linear_subdiv<agg::trans_perspective> interpolator_type;
                    interpolator_type interpolator(tr);

                    typedef image_filter_2x2_type<source_type,
                                                  interpolator_type> span_gen_type;
                    span_gen_type sg(source, interpolator, filter);
                    agg::render_scanlines_aa(g_rasterizer, g_scanline, rb_pre, sa, sg);
                }
                break;
            }

//.........这里部分代码省略.........