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|
//
// AggPas 2.4 RM3 Demo application
// Note: Press F1 key on run to see more info about this demo
//
// Paths: ..;..\ctrl;..\svg;..\util;..\platform\win;expat-wrap
//
program
perspective ;
{DEFINE AGG_GRAY8 }
{$DEFINE AGG_BGR24 }
{DEFINE AGG_RGB24 }
{DEFINE AGG_BGRA32 }
{DEFINE AGG_RGBA32 }
{DEFINE AGG_ARGB32 }
{DEFINE AGG_ABGR32 }
{DEFINE AGG_RGB565 }
{DEFINE AGG_RGB555 }
uses
agg_basics ,
agg_platform_support ,
agg_ctrl ,
agg_rbox_ctrl ,
agg_rasterizer_scanline_aa ,
agg_scanline ,
agg_scanline_p ,
agg_renderer_base ,
agg_renderer_scanline ,
agg_render_scanlines ,
agg_path_storage ,
agg_bounding_rect ,
agg_trans_affine ,
agg_trans_bilinear ,
agg_trans_perspective ,
agg_conv_transform ,
agg_conv_stroke ,
agg_conv_clip_polygon ,
agg_ellipse ,
interactive_polygon_ ,
parse_lion_
{$I pixel_formats.inc }
{$I agg_mode.inc }
const
flip_y = true;
var
g_rasterizer : rasterizer_scanline_aa;
g_scanline : scanline_p8;
g_path : path_storage;
g_colors : array[0..99 ] of aggclr;
g_path_idx : array[0..99 ] of unsigned;
g_npaths : unsigned;
g_x1 ,g_y1 ,g_x2 ,g_y2 ,
g_base_dx ,g_base_dy ,
g_angle ,g_scale ,
g_skew_x ,g_skew_y : double;
g_nclick : int;
type
the_application = object(platform_support )
m_quad : interactive_polygon;
m_trans_type : rbox_ctrl;
constructor Construct(format_ : pix_format_e; flip_y_ : boolean );
destructor Destruct;
procedure on_init; virtual;
procedure on_draw; virtual;
procedure on_mouse_move (x ,y : int; flags : unsigned ); virtual;
procedure on_mouse_button_down(x ,y : int; flags : unsigned ); virtual;
procedure on_mouse_button_up (x ,y : int; flags : unsigned ); virtual;
procedure on_key(x ,y : int; key ,flags : unsigned ); virtual;
end;
{ _PARSE_LION_ }
procedure _parse_lion_;
begin
g_npaths:=parse_lion(@g_path ,@g_colors ,@g_path_idx );
bounding_rect(@g_path ,@g_path_idx ,0 ,g_npaths ,@g_x1 ,@g_y1 ,@g_x2 ,@g_y2 );
g_base_dx:=(g_x2 - g_x1 ) / 2.0;
g_base_dy:=(g_y2 - g_y1 ) / 2.0;
g_path.flip_x(g_x1 ,g_x2 );
g_path.flip_y(g_y1 ,g_y2 );
end;
{ CONSTRUCT }
constructor the_application.Construct;
begin
inherited Construct(format_ ,flip_y_ );
m_quad.Construct (4 ,5.0 );
m_trans_type.Construct(420 ,5.0 ,420 + 130.0 ,55.0 ,not flip_y_ );
_parse_lion_;
m_quad.xn_ptr(0 )^:=g_x1;
m_quad.yn_ptr(0 )^:=g_y1;
m_quad.xn_ptr(1 )^:=g_x2;
m_quad.yn_ptr(1 )^:=g_y1;
m_quad.xn_ptr(2 )^:=g_x2;
m_quad.yn_ptr(2 )^:=g_y2;
m_quad.xn_ptr(3 )^:=g_x1;
m_quad.yn_ptr(3 )^:=g_y2;
m_trans_type.add_item ('Bilinear' );
m_trans_type.add_item ('Perspective' );
m_trans_type.cur_item_(0 );
add_ctrl(@m_trans_type );
end;
{ DESTRUCT }
destructor the_application.Destruct;
begin
inherited Destruct;
m_quad.Destruct;
m_trans_type.Destruct;
end;
{ ON_INIT }
procedure the_application.on_init;
var
dx ,dy : double;
begin
dx:=_width / 2.0 - (m_quad.xn_ptr(1 )^ - m_quad.xn_ptr(0 )^ ) / 2.0;
dy:=_height / 2.0 - (m_quad.yn_ptr(2 )^ - m_quad.yn_ptr(0 )^ ) / 2.0;
m_quad.xn_ptr(0 )^:=m_quad.xn_ptr(0 )^ + dx;
m_quad.yn_ptr(0 )^:=m_quad.yn_ptr(0 )^ + dy;
m_quad.xn_ptr(1 )^:=m_quad.xn_ptr(1 )^ + dx;
m_quad.yn_ptr(1 )^:=m_quad.yn_ptr(1 )^ + dy;
m_quad.xn_ptr(2 )^:=m_quad.xn_ptr(2 )^ + dx;
m_quad.yn_ptr(2 )^:=m_quad.yn_ptr(2 )^ + dy;
m_quad.xn_ptr(3 )^:=m_quad.xn_ptr(3 )^ + dx;
m_quad.yn_ptr(3 )^:=m_quad.yn_ptr(3 )^ + dy;
end;
{ ON_DRAW }
procedure the_application.on_draw;
var
pixf : pixel_formats;
rb : renderer_base;
r : renderer_scanline_aa_solid;
rgba : aggclr;
tr_bi : trans_bilinear;
tr_pe ,
tr2 : trans_perspective23;
trans : conv_transform;
ell : ellipse;
ell_stroke : conv_stroke;
trans_ell ,
trans_ell_stroke : conv_transform;
x ,y : double;
begin
// Initialize structures
pixfmt(pixf ,rbuf_window );
rb.Construct(@pixf );
r.Construct (@rb );
rgba.ConstrDbl(1 ,1 ,1 );
rb.clear (@rgba );
g_rasterizer.clip_box(0 ,0 ,_width ,_height );
// Perspective rendering
if m_trans_type._cur_item = 0 then
begin
tr_bi.Construct(g_x1 ,g_y1 ,g_x2 ,g_y2 ,m_quad.polygon );
if tr_bi.is_valid then
begin
// Render transformed lion
trans.Construct (@g_path ,@tr_bi );
render_all_paths(@g_rasterizer ,@g_scanline ,@r ,@trans ,@g_colors ,@g_path_idx ,g_npaths );
// Render transformed ellipse
ell.Construct(
(g_x1 + g_x2 ) * 0.5 ,(g_y1 + g_y2 ) * 0.5 ,
(g_x2 - g_x1 ) * 0.5 ,(g_y2 - g_y1 ) * 0.5 ,200 );
ell_stroke.Construct(@ell );
ell_stroke.width_ (3.0 );
trans_ell.Construct (@ell ,@tr_bi );
trans_ell_stroke.Construct(@ell_stroke ,@tr_bi );
g_rasterizer.add_path(@trans_ell );
rgba.ConstrDbl(0.5 ,0.3 ,0.0 ,0.3 );
r.color_ (@rgba );
render_scanlines(@g_rasterizer ,@g_scanline ,@r );
g_rasterizer.add_path(@trans_ell_stroke );
rgba.ConstrDbl(0.0 ,0.3 ,0.2 ,1.0 );
r.color_ (@rgba );
render_scanlines(@g_rasterizer ,@g_scanline ,@r );
// Free
ell_stroke.Destruct;
end;
end
else
begin
tr_pe.Construct(g_x1 ,g_y1 ,g_x2 ,g_y2 ,m_quad.polygon );
if tr_pe.is_valid then
begin
// Render transformed lion
trans.Construct(@g_path ,@tr_pe );
render_all_paths(@g_rasterizer ,@g_scanline ,@r ,@trans ,@g_colors ,@g_path_idx ,g_npaths );
// Render transformed ellipse
ell.Construct(
(g_x1 + g_x2 ) * 0.5 ,(g_y1 + g_y2 ) * 0.5 ,
(g_x2 - g_x1 ) * 0.5 ,(g_y2 - g_y1 ) * 0.5 ,200 );
ell_stroke.Construct(@ell );
ell_stroke.width_ (3.0 );
trans_ell.Construct (@ell ,@tr_pe );
trans_ell_stroke.Construct(@ell_stroke ,@tr_pe );
g_rasterizer.add_path(@trans_ell );
rgba.ConstrDbl(0.5 ,0.3 ,0.0 ,0.3 );
r.color_ (@rgba );
render_scanlines(@g_rasterizer ,@g_scanline ,@r );
g_rasterizer.add_path(@trans_ell_stroke );
rgba.ConstrDbl(0.0 ,0.3 ,0.2 ,1.0 );
r.color_ (@rgba );
render_scanlines(@g_rasterizer ,@g_scanline ,@r );
// Free
ell_stroke.Destruct;
// Testing the reverse transformations
{ tr2.Construct(m_quad.polygon ,g_x1 ,g_y1 ,g_x2 ,g_y2 );
if tr2.is_valid then
begin
x:=m_quad.xn_ptr(0 )^;
y:=m_quad.yn_ptr(0 )^;
tr2.transform (@tr2 ,@x ,@y );
g_rasterizer.move_to_d(x ,y );
x:=m_quad.xn_ptr(1 )^;
y:=m_quad.yn_ptr(1 )^;
tr2.transform (@tr2 ,@x ,@y );
g_rasterizer.line_to_d(x ,y );
x:=m_quad.xn_ptr(2 )^;
y:=m_quad.yn_ptr(2 )^;
tr2.transform (@tr2 ,@x ,@y );
g_rasterizer.line_to_d(x ,y );
x:=m_quad.xn_ptr(3 )^;
y:=m_quad.yn_ptr(3 )^;
tr2.transform (@tr2 ,@x ,@y );
g_rasterizer.line_to_d(x ,y );
rgba.ConstrDbl(0.5 ,0.0 ,0.0 ,0.5 );
r.color_ (@rgba );
render_scanlines(@g_rasterizer ,@g_scanline ,@r );
end
else
message_('Singularity...' );{}
end;
end;
// Render the "quad" tool and controls
g_rasterizer.add_path(@m_quad );
rgba.ConstrDbl(0 ,0.3 ,0.5 ,0.6 );
r.color_ (@rgba );
render_scanlines(@g_rasterizer ,@g_scanline ,@r );
render_ctrl (@g_rasterizer ,@g_scanline ,@r ,@m_trans_type );
end;
{ ON_MOUSE_MOVE }
procedure the_application.on_mouse_move;
begin
if flags and mouse_left <> 0 then
if m_quad.on_mouse_move(x ,y ) then
force_redraw;
if flags and mouse_left = 0 then
on_mouse_button_up(x ,y ,flags );
end;
{ ON_MOUSE_BUTTON_DOWN }
procedure the_application.on_mouse_button_down;
begin
if flags and mouse_left <> 0 then
if m_quad.on_mouse_button_down(x ,y ) then
force_redraw;
end;
{ ON_MOUSE_BUTTON_UP }
procedure the_application.on_mouse_button_up;
begin
if m_quad.on_mouse_button_up(x ,y ) then
force_redraw;
end;
{ ON_KEY }
procedure the_application.on_key;
begin
if key = key_f1 then
message_(
'Perspective and bilinear transformations. In general, these classes can transform '#13 +
'an arbitrary quadrangle to another arbitrary quadrangle (with some restrictions). '#13 +
'The example demonstrates how to transform a rectangle to a quadrangle defined by '#13 +
'4 vertices. Note, that the perspective transformations don''t work correctly if '#13 +
'the destination quadrangle is concave. Bilinear thansformations give a different '#13 +
'result, but remain valid with any shape of the destination quadrangle.'#13#13 +
'How to play with:'#13#13 +
'You can drag the 4 corners of the quadrangle, as well as its boundaries.' +
#13#13'Note: F2 key saves current "screenshot" file in this demo''s directory. ' );
end;
VAR
app : the_application;
BEGIN
// Rendering
g_rasterizer.Construct;
g_scanline.Construct;
g_path.Construct;
g_npaths:=0;
g_x1:=0;
g_y1:=0;
g_x2:=0;
g_y2:=0;
g_base_dx:=0;
g_base_dy:=0;
g_angle:=0;
g_scale:=1.0;
g_skew_x:=0;
g_skew_y:=0;
g_nclick:=0;
// App
app.Construct(pix_format ,flip_y );
app.caption_ ('AGG Example. Perspective Transformations (F1-Help)' );
if app.init(600 ,600 ,window_resize ) then
app.run;
app.Destruct;
// Free
g_rasterizer.Destruct;
g_scanline.Destruct;
g_path.Destruct;
END.
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