TFPCustomBrush: what changed

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Title: TFPCustomBrush

New		Line
1	+	`TFPCustomBrush` is a fundamental property of `TFPCustomCanvas` and defines how a geometric shape is filled in fcl-image.
2	+
3	+	## Properties
4	+
5	+	- `Canvas`: points to the `TFPCustomCanvas` on which the brush operates. The property is inherited from the ancestor `TFPCanvasHelper`.
6	+	- `FPColor`: specifies the basic color (type `TFPColor`) used to fill the shape (inherited from ancestor `TFPCanvasHelper`).
7	+	- `Style`: an enumeration of type `TFPBrushStyle` which defines the pattern used for filling:
8	+	- `bsClear`: no filling at all, `FPColor` is ignored.
9	+	- `bsSolid`: uniform fill of the shape with the `FPColor` specified
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	+	- `bsHorizontal`, `bsVertical`, `bsFDiagonal`, `bsBDiagonal` define a single-line hatch pattern.
12	+	- `bsCross` and `bsDiagCross` define a crossed pattern.
13	+	- `bsImage`: fills the shape by tiling the picture given in property `Image` on the canvas.
14	+	- `bsPattern`: uses a custom pattern to fill the shape. The pattern is given by property `Pattern`. See below.
15	+	- `Image`: specifies the image (type `TFPCustomImage`) used when `Style` is `bsImage`. The alpha channel is respected.
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	+
18	+	These properties are applied in all subsequent drawing commands.
19	+
20	+	> Note: The advanced styles `bsImage` and `bsPattern` are availabel for non-rectangular shapes only for FPC v3.3.1+
21	+
22	+	## Methods
23	+
24	+	- `function CopyBrush: TFPCustomBrush`: creates a new brush and copies the current properties to it.
25	+
26	+	## Sample code
27	+
28	+	### Filling a circle with an image pattern (`bsImage`)
29	+
30	+	<figure>
31	+	<img src="fpcustombrush_bsimage.png" title="fpcustombrush_bsimage.png" />
32	+	<figcaption>fpcustombrush_bsimage.png</figcaption>
33	+	</figure>
34	+
35	+	``` Pascal
36	+	program project1;
37	+
38	+	uses
39	+	classes, FPImage, FPCanvas, FPImgCanv, FPReadPNG, FPWritePNG;
40	+
41	+	var
42	+	image: TFPCustomImage;
43	+	pattern: TFPCustomImage;
44	+	canvas: TFPCustomCanvas;
45	+	writer: TFPCustomImageWriter;
46	+
47	+	begin
48	+	// "pattern.png" is some png image (with alpha channel).
49	+	// Select one from the Lazarus image collection in (lazarus)/images
50	+	pattern := TFPMemoryImage.Create(0, 0);
51	+	pattern.LoadFromFile('pattern.png');
52	+
53	+	image := TFPMemoryImage.Create(200,200);
54	+	try
55	+	canvas := TFPImageCanvas.Create(image);
56	+	try
57	+	// Set the pen style
58	+	canvas.Pen.Mode := pmCopy;
59	+	canvas.Pen.Style := psSolid;
60	+	canvas.Pen.Width := 1;
61	+	canvas.Pen.FPColor := colWhite;
62	+
63	+	// Set the brush for the circle: the image stored in "pattern"
64	+	canvas.Brush.Style := bsImage;
65	+	canvas.Brush.Image := pattern;
66	+	// Draw a circle filled by "pattern"
67	+	canvas.Ellipse(10, 10, 90, 90);
68	+
69	+	// Save to file
70	+	writer := TFPWriterPNG.Create;
71	+	try
72	+	// Activate alpha channel in saved image
73	+	TFPWriterPNG(writer).UseAlpha := true;
74	+	// Write image to file
75	+	image.SaveToFile('DrawTest.png', writer);
76	+	finally
77	+	writer.Free;
78	+	end;
79	+
80	+	finally
81	+	canvas.Free;
82	+	end;
83	+
84	+	finally
85	+	pattern.Free;
86	+	image.Free;
87	+	end;
88	+	end.
89	+	```
90	+
91	+	### Filling a rectangle with a custom pattern (`bsPattern`)
92	+
93	+	<figure>
94	+	<img src="fpcustombrush_bspattern.png" title="fpcustombrush_bspattern.png" />
95	+	<figcaption>fpcustombrush_bspattern.png</figcaption>
96	+	</figure>
97	+
98	+	``` pascal
99	+	program project1;
100	+
101	+	uses
102	+	classes, sysutils,
103	+	FPImage, FPCanvas, FPImgCanv, FPWritePNG;
104	+
105	+	const
106	+	BIT_PATTERN: TBrushPattern = (
107	+	%11111111111111111111111111111111, // 1
108	+	%11111111111000000000001111111111, // 2
109	+	%11111111110000000000000111111111, // 3
110	+	%11111111100000000000000011111111, // 4
111	+	%11111111000000000000000001111111, // 5
112	+	%11111110000000000000000000111111, // 6
113	+	%11111100000000000000000000011111, // 7
114	+	%11111000000000000000000000001111, // 8
115	+	%11110000000000000000000000000111, // 9
116	+	%11100000000000000000000000000011, // 10
117	+	%11000000000000001000000000000001, // 11
118	+	%10000000000000011100000000000000, // 12
119	+	%10000000000000111110000000000000, // 13
120	+	%10000000000001111111000000000000, // 14
121	+	%10000000000011110111100000000000, // 15
122	+	%10000000000111100011110000000000, // 16
123	+	%10000000000011110111100000000000, // 17
124	+	%10000000000001111111000000000000, // 18
125	+	%10000000000000111110000000000000, // 19
126	+	%10000000000000011100000000000000, // 20
127	+	%10000000000000001000000000000000, // 21
128	+	%10000000000000000000000000000000, // 22
129	+	%11000000000000000000000000000001, // 23
130	+	%11100000000000000000000000000011, // 24
131	+	%11110000000000000000000000000111, // 25
132	+	%11111000000000000000000000001111, // 26
133	+	%11111100000000000000000000011111, // 27
134	+	%11111110000000000000000000111111, // 28
135	+	%11111111000000000000000001111111, // 29
136	+	%11111111100000000000000011111111, // 30
137	+	%11111111110000000000000111111111, // 31
138	+	%11111111111000000000001111111111 // 32
139	+	);
140	+
141	+	var
142	+	image: TFPCustomImage;
143	+	canvas: TFPCustomCanvas;
144	+	writer: TFPCustomImageWriter;
145	+
146	+	begin
147	+	image := TFPMemoryImage.Create(200, 200);
148	+	try
149	+	canvas := TFPImageCanvas.Create(image);
150	+	try
151	+	// Set the pen style
152	+	canvas.Pen.Mode := pmCopy;
153	+	canvas.Pen.Style := psSolid;
154	+	canvas.Pen.Width := 3;
155	+	canvas.Pen.FPColor := colNavy;
156	+
157	+	// Set the brush for the rectangle: a bit pattern
158	+	// Unless the shape should be transparent draw the background first
159	+	canvas.Brush.Style := bsSolid;
160	+	canvas.Brush.FPColor := colYellow;
161	+	canvas.Rectangle(10, 110, 190, 190);
162	+	// Now draw the pattern
163	+	canvas.Brush.Style := bsPattern;
164	+	canvas.Brush.FPColor := colBlue; // Color for every set bit (1) in the pattern
165	+	canvas.Brush.Pattern := BIT_PATTERN;
166	+	canvas.Rectangle(10, 110, 190, 190);
167	+
168	+	// Save to file
169	+	writer := TFPWriterPNG.Create;
170	+	try
171	+	// Activate alpha channel in saved image
172	+	TFPWriterPNG(writer).UseAlpha := true;
173	+	// Write image to file
174	+	image.SaveToFile('DrawTest.png', writer);
175	+	finally
176	+	writer.Free;
177	+	end;
178	+
179	+	finally
180	+	canvas.Free;
181	+	end;
182	+	finally
183	+	image.Free;
184	+	end;
185	+	end.
186	+	```
187	+
188	+	---
189	+	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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