TFPCustomBrush: what changed

Revision 1 to 2. Removed lines have a minus sign; added lines have a plus sign.

Old	New		Line
1	1		`TFPCustomBrush` is a fundamental property of `TFPCustomCanvas` and defines how a geometric shape is filled in fcl-image.
2	2
3	3		## Properties
4	4
5	5		- `Canvas`: points to the `TFPCustomCanvas` on which the brush operates. The property is inherited from the ancestor `TFPCanvasHelper`.
6	6		- `FPColor`: specifies the basic color (type `TFPColor`) used to fill the shape (inherited from ancestor `TFPCanvasHelper`).
7	7		- `Style`: an enumeration of type `TFPBrushStyle` which defines the pattern used for filling:
8	8		- `bsClear`: no filling at all, `FPColor` is ignored.
9	9		- `bsSolid`: uniform fill of the shape with the `FPColor` specified
10	10		- The following styles define hatch patterns which are drawn in the `FPColor` specified. The background between the hatch lines is left empty, it can only be filled by drawing the shape with `bsSolid` before.
11	11		- `bsHorizontal`, `bsVertical`, `bsFDiagonal`, `bsBDiagonal` define a single-line hatch pattern.
12	12		- `bsCross` and `bsDiagCross` define a crossed pattern.
13	13		- `bsImage`: fills the shape by tiling the picture given in property `Image` on the canvas.
14	14		- `bsPattern`: uses a custom pattern to fill the shape. The pattern is given by property `Pattern`. See below.
15	15		- `Image`: specifies the image (type `TFPCustomImage`) used when `Style` is `bsImage`. The alpha channel is respected.
16	16		- `Pattern`: specifies the custom pattern for filling the shape when `Style` is `bsPattern`. The pattern is defined as a 32-element array of `LongInt` values. This sets up a matrix of 32x32 bits. Each one-bit corresponds to a colored pixel. Pixels corresponding to zero-bits are not drawn.
17	17
18	18		These properties are applied in all subsequent drawing commands.
19	19
20	20		> Note: The advanced styles `bsImage` and `bsPattern` are availabel for non-rectangular shapes only for FPC v3.3.1+
21	21
22	22		## Methods
23	23
24	24		- `function CopyBrush: TFPCustomBrush`: creates a new brush and copies the current properties to it.
25	25
26	26		## Sample code
27	27
28	28		### Filling a circle with an image pattern (`bsImage`)
29	29
30		-	~~<figure>~~
31		-	~~<img src="fpcustombrush_bsimage.png" title="fpcustombrush_bsimage.png" />~~
32		-	~~<figcaption>fpcustombrush_bsimage.png</figcaption>~~
33		-	~~</figure>~~
	30	+	![](/wiki-images/b/b6/Fpcustombrush_bsimage.png)
34	31
35	32		``` Pascal
36	33		program project1;
37	34
38	35		uses
39	36		classes, FPImage, FPCanvas, FPImgCanv, FPReadPNG, FPWritePNG;
40	37
41	38		var
42	39		image: TFPCustomImage;
43	40		pattern: TFPCustomImage;
44	41		canvas: TFPCustomCanvas;
45	42		writer: TFPCustomImageWriter;
46	43
47	44		begin
48	45		// "pattern.png" is some png image (with alpha channel).
49	46		// Select one from the Lazarus image collection in (lazarus)/images
50	47		pattern := TFPMemoryImage.Create(0, 0);
51	48		pattern.LoadFromFile('pattern.png');
52	49
53	50		image := TFPMemoryImage.Create(200,200);
54	51		try
55	52		canvas := TFPImageCanvas.Create(image);
56	53		try
57	54		// Set the pen style
58	55		canvas.Pen.Mode := pmCopy;
59	56		canvas.Pen.Style := psSolid;
60	57		canvas.Pen.Width := 1;
61	58		canvas.Pen.FPColor := colWhite;
62	59
63	60		// Set the brush for the circle: the image stored in "pattern"
64	61		canvas.Brush.Style := bsImage;
65	62		canvas.Brush.Image := pattern;
66	63		// Draw a circle filled by "pattern"
67	64		canvas.Ellipse(10, 10, 90, 90);
68	65
69	66		// Save to file
70	67		writer := TFPWriterPNG.Create;
71	68		try
72	69		// Activate alpha channel in saved image
73	70		TFPWriterPNG(writer).UseAlpha := true;
74	71		// Write image to file
75	72		image.SaveToFile('DrawTest.png', writer);
76	73		finally
77	74		writer.Free;
78	75		end;
79	76
80	77		finally
81	78		canvas.Free;
82	79		end;
83	80
84	81		finally
85	82		pattern.Free;
86	83		image.Free;
87	84		end;
88	85		end.
89	86		```
90	87
91	88		### Filling a rectangle with a custom pattern (`bsPattern`)
92	89
93		-	~~<figure>~~
94		-	~~<img src="fpcustombrush_bspattern.png" title="fpcustombrush_bspattern.png" />~~
95		-	~~<figcaption>fpcustombrush_bspattern.png</figcaption>~~
96		-	~~</figure>~~
	90	+	![](/wiki-images/e/e0/Fpcustombrush_bspattern.png)
97	91
98	92		``` pascal
99	93		program project1;
100	94
101	95		uses
102	96		classes, sysutils,
103	97		FPImage, FPCanvas, FPImgCanv, FPWritePNG;
104	98
105	99		const
106	100		BIT_PATTERN: TBrushPattern = (
107	101		%11111111111111111111111111111111, // 1
108	102		%11111111111000000000001111111111, // 2
109	103		%11111111110000000000000111111111, // 3
110	104		%11111111100000000000000011111111, // 4
111	105		%11111111000000000000000001111111, // 5
112	106		%11111110000000000000000000111111, // 6
113	107		%11111100000000000000000000011111, // 7
114	108		%11111000000000000000000000001111, // 8
115	109		%11110000000000000000000000000111, // 9
116	110		%11100000000000000000000000000011, // 10
117	111		%11000000000000001000000000000001, // 11
118	112		%10000000000000011100000000000000, // 12
119	113		%10000000000000111110000000000000, // 13
120	114		%10000000000001111111000000000000, // 14
121	115		%10000000000011110111100000000000, // 15
122	116		%10000000000111100011110000000000, // 16
123	117		%10000000000011110111100000000000, // 17
124	118		%10000000000001111111000000000000, // 18
125	119		%10000000000000111110000000000000, // 19
126	120		%10000000000000011100000000000000, // 20
127	121		%10000000000000001000000000000000, // 21
128	122		%10000000000000000000000000000000, // 22
129	123		%11000000000000000000000000000001, // 23
130	124		%11100000000000000000000000000011, // 24
131	125		%11110000000000000000000000000111, // 25
132	126		%11111000000000000000000000001111, // 26
133	127		%11111100000000000000000000011111, // 27
134	128		%11111110000000000000000000111111, // 28
135	129		%11111111000000000000000001111111, // 29
136	130		%11111111100000000000000011111111, // 30
137	131		%11111111110000000000000111111111, // 31
138	132		%11111111111000000000001111111111 // 32
139	133		);
140	134
141	135		var
142	136		image: TFPCustomImage;
143	137		canvas: TFPCustomCanvas;
144	138		writer: TFPCustomImageWriter;
145	139
146	140		begin
147	141		image := TFPMemoryImage.Create(200, 200);
148	142		try
149	143		canvas := TFPImageCanvas.Create(image);
150	144		try
151	145		// Set the pen style
152	146		canvas.Pen.Mode := pmCopy;
153	147		canvas.Pen.Style := psSolid;
154	148		canvas.Pen.Width := 3;
155	149		canvas.Pen.FPColor := colNavy;
156	150
157	151		// Set the brush for the rectangle: a bit pattern
158	152		// Unless the shape should be transparent draw the background first
159	153		canvas.Brush.Style := bsSolid;
160	154		canvas.Brush.FPColor := colYellow;
161	155		canvas.Rectangle(10, 110, 190, 190);
162	156		// Now draw the pattern
163	157		canvas.Brush.Style := bsPattern;
164	158		canvas.Brush.FPColor := colBlue; // Color for every set bit (1) in the pattern
165	159		canvas.Brush.Pattern := BIT_PATTERN;
166	160		canvas.Rectangle(10, 110, 190, 190);
167	161
168	162		// Save to file
169	163		writer := TFPWriterPNG.Create;
170	164		try
171	165		// Activate alpha channel in saved image
172	166		TFPWriterPNG(writer).UseAlpha := true;
173	167		// Write image to file
174	168		image.SaveToFile('DrawTest.png', writer);
175	169		finally
176	170		writer.Free;
177	171		end;
178	172
179	173		finally
180	174		canvas.Free;
181	175		end;
182	176		finally
183	177		image.Free;
184	178		end;
185	179		end.
186	180		```
187	181
188	182		---
189	183		From the Free Pascal wiki, page "TFPCustomBrush", as it stood on 2023-11-24 after a change by Wp, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).

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