Hello,
I'm trying to create a nine patch drawer and am having troubles. The problem is with using al_draw_scaled_bitmap. I am scaling a 1 px wide section of a bitmap and there is bleed over.
{"name":"606365","src":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/a\/d\/ad6025472b156cc8f3b7f66bfae959ce.png","w":440,"h":220,"tn":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/a\/d\/ad6025472b156cc8f3b7f66bfae959ce"}
The box on the left is what is being drawn. The box on the right is what is supposed to happen. If the bitmap's scalable area > 1 then there is no issue.
I attached 'button.bmp'
ALLEGRO_BITMAP *button = al_load_bitmap( "button.bmp" ) dNinePatchBitmap *nine = dNinePatchBitmap::create( button ); nine->draw( 200, 100, 200, 200 );
dNinePatchBitmap.h
1#ifndef _D_NINEPATCHBITMAP_H
2#define _D_NINEPATCHBITMAP_H
3
4#include <allegro5/allegro.h>
5#include <allegro5/allegro_image.h>
6
7class dNinePatchBitmap
8{
9public:
10 static dNinePatchBitmap* create( ALLEGRO_BITMAP *bitmap, int x1 = -1, int y1 = -1, int x2 = -1, int y2 = -1 );
11 ~dNinePatchBitmap();
12 void draw( int x, int y, int w, int h );
13
14 ALLEGRO_BITMAP *mBitmap;
15
16 int mWidth;
17 int mHeight;
18 int mStartX1;
19 int mStartX2;
20 int mStartY1;
21 int mStartY2;
22
23private:
24 dNinePatchBitmap();
25};
26
27#endif
dNinePatchBitmap.cpp
1#include "dNinePatchBitmap.h"
2
3dNinePatchBitmap::dNinePatchBitmap()
4{
5 this->mBitmap = 0;
6 this->mWidth = 0;
7 this->mHeight = 0;
8 this->mStartX1 = 0;
9 this->mStartX2 = 0;
10 this->mStartY1 = 0;
11 this->mStartY2 = 0;
12}
13
14dNinePatchBitmap::~dNinePatchBitmap()
15{
16 if ( this->mBitmap )
17 {
18 al_destroy_bitmap( this->mBitmap );
19 }
20}
21
22dNinePatchBitmap* dNinePatchBitmap::create( ALLEGRO_BITMAP *bitmap, int x1, int y1, int x2, int y2 )
23{
24 dNinePatchBitmap* ninePatch = 0;
25
26 if ( bitmap )
27 {
28 if ( x1 == -1 ) { x1 = 0; };
29 if ( y1 == -1 ) { y1 = 0; };
30 if ( x2 == -1 ) { x2 = al_get_bitmap_width( bitmap ) - 1; };
31 if ( y2 == -1 ) { y2 = al_get_bitmap_height( bitmap ) - 1; };
32
33 ninePatch = new dNinePatchBitmap();
34
35 if ( ninePatch )
36 {
37 ninePatch->mWidth = ( x2 - x1 );
38 ninePatch->mHeight = ( y2 - y1 );
39 ninePatch->mBitmap = al_create_bitmap( ninePatch->mWidth, ninePatch->mHeight );
40
41 if ( ninePatch->mBitmap )
42 {
43 unsigned char r = 0;
44 unsigned char g = 0;
45 unsigned char b = 0;
46 ALLEGRO_BITMAP *target = al_get_target_bitmap();
47
48 al_set_target_bitmap( ninePatch->mBitmap );
49
50 al_draw_bitmap_region( bitmap, x1 + 1, y1 + 1, ninePatch->mWidth, ninePatch->mHeight, 0, 0, 0 );
51
52 al_lock_bitmap( ninePatch->mBitmap, ALLEGRO_PIXEL_FORMAT_ANY, ALLEGRO_LOCK_READONLY );
53
54 for ( int i = 0; i <= ninePatch->mWidth; i++ )
55 {
56 al_unmap_rgb( al_get_pixel( bitmap, x1 + i, 0 ), &r, &g, &b );
57
58 if ( r == 0 && g == 0 && b == 0 )
59 {
60 ninePatch->mStartX1 = i - 1;
61 break;
62 }
63 }
64
65 for ( int i = ninePatch->mStartX1 + 1; i <= ninePatch->mWidth; i++ )
66 {
67 al_unmap_rgb( al_get_pixel( bitmap, x1 + i, 0 ), &r, &g, &b );
68
69 if ( !( r == 0 && g == 0 && b == 0 ) )
70 {
71 break;
72 }
73
74 ninePatch->mStartX2 = i;
75 }
76
77 for ( int j = 0; j <= ninePatch->mHeight; j++ )
78 {
79 al_unmap_rgb( al_get_pixel( bitmap, 0, y1 + j ), &r, &g, &b );
80
81 if ( r == 0 && g == 0 && b == 0 )
82 {
83 ninePatch->mStartY1 = j - 1;
84 break;
85 }
86 }
87
88 for ( int j = ninePatch->mStartY1 + 1; j <= ninePatch->mHeight; j++ )
89 {
90 al_unmap_rgb( al_get_pixel( bitmap, 0, y1 + j ), &r, &g, &b );
91
92 if ( !( r == 0 && g == 0 && b == 0 ) )
93 {
94 break;
95 }
96
97 ninePatch->mStartY2 = j;
98 }
99
100 al_unlock_bitmap( ninePatch->mBitmap );
101
102
103 al_convert_mask_to_alpha( ninePatch->mBitmap, al_map_rgb( 255, 0, 255 ) );
104
105 al_set_target_bitmap( target );
106 }
107 else
108 {
109 delete ninePatch;
110 }
111 }
112 }
113
114 return ninePatch;
115}
116
117void dNinePatchBitmap::draw( int x, int y, int w, int h )
118{
119// s e
120// ........----------.......
121// 0123456789012345678901234
122// 1 2 3
123
124 int x1 = 0;
125 int x2 = this->mStartX1;
126 int x3 = this->mStartX2;
127
128 int y1 = 0;
129 int y2 = this->mStartY1;
130 int y3 = this->mStartY2;
131
132 int w1 = ( x2 - x1 );
133 int w2 = ( x3 - x2 );
134 int w3 = ( this->mWidth - x3 );
135
136 int h1 = ( y2 - y1 );
137 int h2 = ( y3 - y2 );
138 int h3 = ( this->mHeight - y3 );
139
140 int stretchW = w - ( w1 + w3 );
141 int stretchH = h - ( h1 + h3 );
142
143 // upper left
144 al_draw_bitmap_region( this->mBitmap, x1, y1, w1, h1, x, y, 0 );
145
146 // upper right
147 al_draw_bitmap_region( this->mBitmap, x3, y1, w3, h1, x + w - w3, y, 0 );
148
149 // lower left
150 al_draw_bitmap_region( this->mBitmap, x1, y3, w1, h1, x, y + h - h3, 0 );
151
152 // lower right
153 al_draw_bitmap_region( this->mBitmap, x3, y3, w3, h1, x + w - w3, y + h - h3, 0 );
154
155 // upper middle
156 al_draw_scaled_bitmap( this->mBitmap, x2, y1, w2, h1, x + x2, y, stretchW, h1, 0 );
157
158 // middle left
159 al_draw_scaled_bitmap( this->mBitmap, x1, y2, w1, h2, x, y + y2, w1, stretchH, 0 );
160
161
162 // lower middle
163 al_draw_scaled_bitmap( this->mBitmap, x2, y3, w2, h3, x + x2, y + h - h3, stretchW, h3, 0 );
164
165 // middle right
166 al_draw_scaled_bitmap( this->mBitmap, x3, y2, w3, h2, x + w - w3, y + y2, w3, stretchH, 0 );
167
168 // middle
169 al_draw_scaled_bitmap( this->mBitmap, x2, y2, w2, h2, x + x2, y + y2, stretchW, stretchH, 0 );
170}
Any ideas to fix this would be appreciated.
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