#include <stdio.h>
#include "agg_basics.h"
#include "agg_rendering_buffer.h"
#include "agg_rasterizer_scanline_aa.h"
#include "agg_scanline_p.h"
#include "agg_renderer_scanline.h"
#include "agg_renderer_primitives.h"
#include "agg_conv_curve.h"
#include "agg_conv_stroke.h"
#include "agg_gsv_text.h"
#include "agg_pixfmt_rgb.h"
#include "agg_pixfmt_gray.h"
#include "agg_pixfmt_amask_adaptor.h"
#include "agg_span_allocator.h"
#include "agg_alpha_mask_u8.h"

#include "platform/agg_platform_support.h"

#include "ctrl/agg_slider_ctrl.h"
#include "ctrl/agg_cbox_ctrl.h"
#include "ctrl/agg_rbox_ctrl.h"


enum flip_y_e { flip_y = true };




class spiral
{
public:
    spiral(double x, double y, double r1, double r2, double step, double start_angle=0) :
        m_x(x), 
        m_y(y), 
        m_r1(r1), 
        m_r2(r2), 
        m_step(step), 
        m_start_angle(start_angle),
        m_angle(start_angle),
        m_da(agg::deg2rad(4.0)),
        m_dr(m_step / 90.0)
    {
    }

    void rewind(unsigned) 
    { 
        m_angle = m_start_angle; 
        m_curr_r = m_r1; 
        m_start = true; 
    }

    unsigned vertex(double* x, double* y)
    {
        if(m_curr_r > m_r2) return agg::path_cmd_stop;

        *x = m_x + cos(m_angle) * m_curr_r;
        *y = m_y + sin(m_angle) * m_curr_r;
        m_curr_r += m_dr;
        m_angle += m_da;
        if(m_start) 
        {
            m_start = false;
            return agg::path_cmd_move_to;
        }
        return agg::path_cmd_line_to;
    }

private:
    double m_x;
    double m_y;
    double m_r1;
    double m_r2;
    double m_step;
    double m_start_angle;

    double m_angle;
    double m_curr_r;
    double m_da;
    double m_dr;
    bool   m_start;
};





void make_gb_poly(agg::path_storage& ps);
void make_arrows(agg::path_storage& ps);


class the_application : public agg::platform_support
{
    agg::rbox_ctrl<agg::rgba8> m_polygons;
    agg::rbox_ctrl<agg::rgba8> m_operation;

    typedef agg::amask_no_clip_gray8 alpha_mask_type;
    //typedef agg::alpha_mask_gray8 alpha_mask_type;

    typedef agg::pixfmt_bgr24 pixfmt_type;

    unsigned char* m_alpha_buf;
    agg::rendering_buffer m_alpha_mask_rbuf;
    alpha_mask_type m_alpha_mask;
    agg::rasterizer_scanline_aa<> m_ras;
    agg::scanline_p8              m_sl;

    double m_x;
    double m_y;

public:
    ~the_application()
    {
        delete [] m_alpha_buf;
    }
    
    the_application(agg::pix_format_e format, bool flip_y) :
        agg::platform_support(format, flip_y),
        m_polygons (5.0,     5.0, 5.0+205.0,  110.0,  !flip_y),
        m_operation(555.0,   5.0, 555.0+80.0, 55.0,  !flip_y),
        m_alpha_buf(0),
        m_alpha_mask_rbuf(),
        m_alpha_mask(m_alpha_mask_rbuf),
        m_x(0),
        m_y(0)
    {
        m_operation.add_item("AND");
        m_operation.add_item("SUB");
        m_operation.cur_item(0);
        add_ctrl(m_operation);
        m_operation.no_transform();

        m_polygons.add_item("Two Simple Paths");
        m_polygons.add_item("Closed Stroke");
        m_polygons.add_item("Great Britain and Arrows");
        m_polygons.add_item("Great Britain and Spiral");
        m_polygons.add_item("Spiral and Glyph");
        m_polygons.cur_item(3);
        add_ctrl(m_polygons);
        m_polygons.no_transform();
    }


    void draw_text(double x, double y, const char* str)
    {
        pixfmt_type pf(rbuf_window());
        agg::renderer_base<pixfmt_type> rb(pf);
        agg::renderer_scanline_aa_solid<agg::renderer_base<pixfmt_type> > ren(rb);

        agg::gsv_text txt;
        agg::conv_stroke<agg::gsv_text> txt_stroke(txt);
        txt_stroke.width(1.5);
        txt_stroke.line_cap(agg::round_cap);
        txt.size(10.0);
        txt.start_point(x, y);
        txt.text(str);
        m_ras.add_path(txt_stroke);
        ren.color(agg::rgba(0.0, 0.0, 0.0));
        agg::render_scanlines(m_ras, m_sl, ren);
    }


    template<class VertexSource> void generate_alpha_mask(VertexSource& vs)
    {
        unsigned cx = (unsigned)width();
        unsigned cy = (unsigned)height();

        delete [] m_alpha_buf;
        m_alpha_buf = new unsigned char[cx * cy];
        m_alpha_mask_rbuf.attach(m_alpha_buf, cx, cy, cx);

        typedef agg::renderer_base<agg::pixfmt_gray8> ren_base;
        typedef agg::renderer_scanline_aa_solid<ren_base> renderer;

        agg::pixfmt_gray8 pixf(m_alpha_mask_rbuf);
        ren_base rb(pixf);
        renderer ren(rb);

        start_timer();
        if(m_operation.cur_item() == 0)
        {
            rb.clear(agg::gray8(0));
            ren.color(agg::gray8(255));
        }
        else 
        {
            rb.clear(agg::gray8(255));
            ren.color(agg::gray8(0));
        }
        m_ras.add_path(vs);
        agg::render_scanlines(m_ras, m_sl, ren);
        double t1 = elapsed_time();

        char buf[100];
        sprintf(buf, "Generate AlphaMask: %.3fms", t1);
        draw_text(250, 20, buf);
    }


    template<class VertexSource>
    void perform_rendering(VertexSource& vs)
    {
        pixfmt_type pixf(rbuf_window());

        typedef agg::pixfmt_amask_adaptor<pixfmt_type, alpha_mask_type> pixfmt_amask_type;
        typedef agg::renderer_base<pixfmt_amask_type>                   amask_ren_type;


        pixfmt_amask_type pixfa(pixf, m_alpha_mask);
        amask_ren_type rbase(pixfa);
        agg::renderer_scanline_aa_solid<amask_ren_type> ren(rbase);

        ren.color(agg::rgba(0.5, 0.0, 0, 0.5));

        start_timer();
        m_ras.reset();
        m_ras.add_path(vs);
        agg::render_scanlines(m_ras, m_sl, ren);
        double t1 = elapsed_time();


        char buf[100];
        sprintf(buf, "Render with AlphaMask: %.3fms", t1);
        draw_text(250, 5, buf);
    }


    unsigned render()
    {
        pixfmt_type pf(rbuf_window());
        agg::renderer_base<pixfmt_type> rb(pf);
        agg::renderer_scanline_aa_solid<agg::renderer_base<pixfmt_type> > ren(rb);

        switch(m_polygons.cur_item())
        {
            case 0:
            {
                //------------------------------------
                // Two simple paths
                //
                agg::path_storage ps1;
                agg::path_storage ps2;

                double x = m_x - initial_width()/2 + 100;
                double y = m_y - initial_height()/2 + 100;
                ps1.move_to(x+140, y+145);
                ps1.line_to(x+225, y+44);
                ps1.line_to(x+296, y+219);
                ps1.close_polygon();

                ps1.line_to(x+226, y+289);
                ps1.line_to(x+82,  y+292);

                ps1.move_to(x+220, y+222);
                ps1.line_to(x+363, y+249);
                ps1.line_to(x+265, y+331);

                ps1.move_to(x+242, y+243);
                ps1.line_to(x+268, y+309);
                ps1.line_to(x+325, y+261);

                ps1.move_to(x+259, y+259);
                ps1.line_to(x+273, y+288);
                ps1.line_to(x+298, y+266);

                ps2.move_to(100+32,  100+77);
                ps2.line_to(100+473, 100+263);
                ps2.line_to(100+351, 100+290);
                ps2.line_to(100+354, 100+374);

                m_ras.reset();
                m_ras.add_path(ps1);
                ren.color(agg::rgba(0, 0, 0, 0.1));
                agg::render_scanlines(m_ras, m_sl, ren);

                m_ras.reset();
                m_ras.add_path(ps2);
                ren.color(agg::rgba(0, 0.6, 0, 0.1));
                agg::render_scanlines(m_ras, m_sl, ren);

                generate_alpha_mask(ps1);
                perform_rendering(ps2);
            }
            break;

            case 1:
            {
                //------------------------------------
                // Closed stroke
                //
                agg::path_storage ps1;
                agg::path_storage ps2;
                agg::conv_stroke<agg::path_storage> stroke(ps2);
                stroke.width(10.0);

                double x = m_x - initial_width()/2 + 100;
                double y = m_y - initial_height()/2 + 100;
                ps1.move_to(x+140, y+145);
                ps1.line_to(x+225, y+44);
                ps1.line_to(x+296, y+219);
                ps1.close_polygon();

                ps1.line_to(x+226, y+289);
                ps1.line_to(x+82,  y+292);

                ps1.move_to(x+220-50, y+222);
                ps1.line_to(x+265-50, y+331);
                ps1.line_to(x+363-50, y+249);
                ps1.close_polygon(agg::path_flags_ccw);

                ps2.move_to(100+32,  100+77);
                ps2.line_to(100+473, 100+263);
                ps2.line_to(100+351, 100+290);
                ps2.line_to(100+354, 100+374);
                ps2.close_polygon();

                m_ras.reset();
                m_ras.add_path(ps1);
                ren.color(agg::rgba(0, 0, 0, 0.1));
                agg::render_scanlines(m_ras, m_sl, ren);

                m_ras.reset();
                m_ras.add_path(stroke);
                ren.color(agg::rgba(0, 0.6, 0, 0.1));
                agg::render_scanlines(m_ras, m_sl, ren);

                generate_alpha_mask(ps1);
                perform_rendering(stroke);
            }
            break;


            case 2:
            {
                //------------------------------------
                // Great Britain and Arrows
                //
                agg::path_storage gb_poly;
                agg::path_storage arrows;
                make_gb_poly(gb_poly);
                make_arrows(arrows);

                agg::trans_affine mtx1;
                agg::trans_affine mtx2;
                mtx1 *= agg::trans_affine_translation(-1150, -1150);
                mtx1 *= agg::trans_affine_scaling(2.0);

                mtx2 = mtx1;
                mtx2 *= agg::trans_affine_translation(m_x - initial_width()/2, 
                                                      m_y - initial_height()/2);

                agg::conv_transform<agg::path_storage> trans_gb_poly(gb_poly, mtx1);
                agg::conv_transform<agg::path_storage> trans_arrows(arrows, mtx2);

                m_ras.add_path(trans_gb_poly);
                ren.color(agg::rgba(0.5, 0.5, 0, 0.1));
                agg::render_scanlines(m_ras, m_sl, ren);

                agg::conv_stroke<agg::conv_transform<agg::path_storage> > stroke_gb_poly(trans_gb_poly);
                stroke_gb_poly.width(0.1);
                m_ras.add_path(stroke_gb_poly);
                ren.color(agg::rgba(0, 0, 0));
                agg::render_scanlines(m_ras, m_sl, ren);
        
                m_ras.add_path(trans_arrows);
                ren.color(agg::rgba(0.0, 0.5, 0.5, 0.1));
                agg::render_scanlines(m_ras, m_sl, ren);

                generate_alpha_mask(trans_gb_poly);
                perform_rendering(trans_arrows);
            }
            break;


            case 3:
            {
                //------------------------------------
                // Great Britain and a Spiral
                //
                spiral sp(m_x, m_y, 10, 150, 30, 0.0);
                agg::conv_stroke<spiral> stroke(sp);
                stroke.width(15.0);

                agg::path_storage gb_poly;
                make_gb_poly(gb_poly);

                agg::trans_affine mtx;
                mtx *= agg::trans_affine_translation(-1150, -1150);
                mtx *= agg::trans_affine_scaling(2.0);

                agg::conv_transform<agg::path_storage> trans_gb_poly(gb_poly, mtx);

                m_ras.add_path(trans_gb_poly);
                ren.color(agg::rgba(0.5, 0.5, 0, 0.1));
                agg::render_scanlines(m_ras, m_sl, ren);

                agg::conv_stroke<agg::conv_transform<agg::path_storage> > stroke_gb_poly(trans_gb_poly);
                stroke_gb_poly.width(0.1);
                m_ras.add_path(stroke_gb_poly);
                ren.color(agg::rgba(0, 0, 0));
                agg::render_scanlines(m_ras, m_sl, ren);
        
                m_ras.add_path(stroke);
                ren.color(agg::rgba(0.0, 0.5, 0.5, 0.1));
                agg::render_scanlines(m_ras, m_sl, ren);

                generate_alpha_mask(trans_gb_poly);
                perform_rendering(stroke);
            }
            break;


            case 4:
            {
                //------------------------------------
                // Spiral and glyph
                //
                spiral sp(m_x, m_y, 10, 150, 30, 0.0);
                agg::conv_stroke<spiral> stroke(sp);
                stroke.width(15.0);

                agg::path_storage glyph;
                glyph.move_to(28.47, 6.45);
                glyph.curve3(21.58, 1.12, 19.82, 0.29);
                glyph.curve3(17.19, -0.93, 14.21, -0.93);
                glyph.curve3(9.57, -0.93, 6.57, 2.25);
                glyph.curve3(3.56, 5.42, 3.56, 10.60);
                glyph.curve3(3.56, 13.87, 5.03, 16.26);
                glyph.curve3(7.03, 19.58, 11.99, 22.51);
                glyph.curve3(16.94, 25.44, 28.47, 29.64);
                glyph.line_to(28.47, 31.40);
                glyph.curve3(28.47, 38.09, 26.34, 40.58);
                glyph.curve3(24.22, 43.07, 20.17, 43.07);
                glyph.curve3(17.09, 43.07, 15.28, 41.41);
                glyph.curve3(13.43, 39.75, 13.43, 37.60);
                glyph.line_to(13.53, 34.77);
                glyph.curve3(13.53, 32.52, 12.38, 31.30);
                glyph.curve3(11.23, 30.08, 9.38, 30.08);
                glyph.curve3(7.57, 30.08, 6.42, 31.35);
                glyph.curve3(5.27, 32.62, 5.27, 34.81);
                glyph.curve3(5.27, 39.01, 9.57, 42.53);
                glyph.curve3(13.87, 46.04, 21.63, 46.04);
                glyph.curve3(27.59, 46.04, 31.40, 44.04);
                glyph.curve3(34.28, 42.53, 35.64, 39.31);
                glyph.curve3(36.52, 37.21, 36.52, 30.71);
                glyph.line_to(36.52, 15.53);
                glyph.curve3(36.52, 9.13, 36.77, 7.69);
                glyph.curve3(37.01, 6.25, 37.57, 5.76);
                glyph.curve3(38.13, 5.27, 38.87, 5.27);
                glyph.curve3(39.65, 5.27, 40.23, 5.62);
                glyph.curve3(41.26, 6.25, 44.19, 9.18);
                glyph.line_to(44.19, 6.45);
                glyph.curve3(38.72, -0.88, 33.74, -0.88);
                glyph.curve3(31.35, -0.88, 29.93, 0.78);
                glyph.curve3(28.52, 2.44, 28.47, 6.45);
                glyph.close_polygon();

                glyph.move_to(28.47, 9.62);
                glyph.line_to(28.47, 26.66);
                glyph.curve3(21.09, 23.73, 18.95, 22.51);
                glyph.curve3(15.09, 20.36, 13.43, 18.02);
                glyph.curve3(11.77, 15.67, 11.77, 12.89);
                glyph.curve3(11.77, 9.38, 13.87, 7.06);
                glyph.curve3(15.97, 4.74, 18.70, 4.74);
                glyph.curve3(22.41, 4.74, 28.47, 9.62);
                glyph.close_polygon();

                agg::trans_affine mtx;
                mtx *= agg::trans_affine_scaling(4.0);
                mtx *= agg::trans_affine_translation(220, 200);
                agg::conv_transform<agg::path_storage> trans(glyph, mtx);
                agg::conv_curve<agg::conv_transform<agg::path_storage> > curve(trans);

                m_ras.reset();
                m_ras.add_path(stroke);
                ren.color(agg::rgba(0, 0, 0, 0.1));
                agg::render_scanlines(m_ras, m_sl, ren);

                m_ras.reset();
                m_ras.add_path(curve);
                ren.color(agg::rgba(0, 0.6, 0, 0.1));
                agg::render_scanlines(m_ras, m_sl, ren);

                generate_alpha_mask(stroke);
                perform_rendering(curve);
            }
            break;
        }

        return 0;
    }


    virtual void on_init()
    {
        m_x = width() / 2.0;
        m_y = height() / 2.0;
    }

    virtual void on_draw()
    {
        typedef agg::renderer_base<pixfmt_type> base_ren_type;

        pixfmt_type pf(rbuf_window());
        base_ren_type ren_base(pf);
        ren_base.clear(agg::rgba(1,1,1));

        render();

        agg::render_ctrl(m_ras, m_sl, ren_base, m_polygons);
        agg::render_ctrl(m_ras, m_sl, ren_base, m_operation);
    }




    virtual void on_mouse_button_down(int x, int y, unsigned flags)
    {
        if(flags & agg::mouse_left)
        {
            m_x = x;
            m_y = y;
            force_redraw();
        }

        if(flags & agg::mouse_right)
        {
            char buf[100];
            sprintf(buf, "%d %d", x, y);
            message(buf);
        }
    }


    virtual void on_mouse_move(int x, int y, unsigned flags)
    {
        if(flags & agg::mouse_left)
        {
            m_x = x;
            m_y = y;
            force_redraw();
        }
    }



};



int agg_main(int argc, char* argv[])
{
    the_application app(agg::pix_format_bgr24, flip_y);
    app.caption("AGG Example. Alpha-Mask as a Polygon Clipper");

    if(app.init(640, 520, agg::window_resize))
    {
        return app.run();
    }
    return 1;
}


Copyright © 2002-2006 Maxim Shemanarev
Web Design and Programming Maxim Shemanarev