I am having the user click a point on screen, and until they choose the second point, the line will follow the cursor. Once the second point is drawn it will stay. I am using a double buffer like so:
public void EnableDoubleBuffering()
{
this.SetStyle(ControlStyles.DoubleBuffer | ControlStyles.UserPaint | ControlStyles.AllPaintingInWmPaint, true);
}
I will call that function in the Form_Load();
I am doing the draw like so:
void draw(int x1, int y1, int x2, int y2)
{
Graphics formGraphics = pictureEdit1.CreateGraphics();
Pen myPen = new Pen(Color.Red, 3);
formGraphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
formGraphics.DrawLine(myPen, x1, y1, x2, y2);
myPen.Dispose();
formGraphics.Dispose();
}
I repetatively call that function from the MouseMove event;
void pictureEdit1_MouseMove(object sender, MouseEventArgs e)
{
if (click == 1 && !rightClicked)
{
pictureEdit1.Invalidate();
trail.X = e.X;
trail.Y = e.Y;
draw(p1.X, p1.Y, trail.X, trail.Y);
}
else if (click != 1)
{
draw(p1.X, p1.Y, trail.X, trail.Y);
}
}
There is a very slight flicker that occurs and it is driving me insane! Please help, thanks.
This code will do what you want, without any flicker. Keep in mind, I don't know what you want to do after the line is drawn, so it will vanish. But this should give you a pretty good idea of how to do this:
public partial class Form1 : Form
{
private Point _firstPoint;
private Point _secondPoint;
private bool _hasClicked;
public Form1()
{
InitializeComponent();
_hasClicked = false;
_firstPoint = new Point();
_secondPoint = new Point();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void pictureEdit1_MouseMove(object sender, MouseEventArgs e)
{
_secondPoint.X = e.X;
_secondPoint.Y = e.Y;
pictureEdit1.Refresh();
}
private void pictureEdit1_MouseUp(object sender, MouseEventArgs e)
{
if (!_hasClicked)
{
_firstPoint.X = e.X;
_firstPoint.Y = e.Y;
}
_hasClicked = !_hasClicked;
pictureEdit1.Refresh();
}
private void pictureEdit1_Paint(object sender, PaintEventArgs e)
{
if (_hasClicked)
e.Graphics.DrawLine(Pens.Red, _firstPoint, _secondPoint);
}
Related
i have a problem.
I'm writing a program that writes on it with a stylus.
First, i create a windows form with a panel.
second, this code:
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Collections;
using System.Diagnostics;
using System.Drawing.Drawing2D;
namespace testWrite
{
public partial class Form1 : Form
{
Graphics g;
int x = -1;
int y = -1;
bool moving = false;
Pen pen;
public Form1()
{
InitializeComponent();
g = panel1.CreateGraphics();
pen = new Pen(Color.Black, 5);
pen.SetLineCap(System.Drawing.Drawing2D.LineCap.Round, System.Drawing.Drawing2D.LineCap.Round, System.Drawing.Drawing2D.DashCap.Round);
pen.StartCap = System.Drawing.Drawing2D.LineCap.Round;
pen.EndCap = System.Drawing.Drawing2D.LineCap.Round;
}
private void panel1_MouseMove(object sender, MouseEventArgs e)
{
if(e.Button == MouseButtons.Left)
{
g.DrawLine(pen, new Point(x, y), e.Location);
x = e.X;
y = e.Y;
}
}
private void panel1_MouseUp(object sender, MouseEventArgs e)
{
x = -1;
y = -1;
moving = false;
}
private void panel1_MouseDown(object sender, MouseEventArgs e)
{
x = e.X;
y = e.Y;
moving = true;
}
}
}
I use this app with a Wacom intuos
But the result is not so good because a few words are lost...haizzz
toi tên la trần
quang hieu
hello heloo
especially, when i write fast or the text is small.
when i write in Microsoft Paint, it is very good
What is best way to to write in windows forms with pen-tablet like wacom intuos?
UPDATE 1:
With cmt from TaW.
Thanks for your help. But, that's not what I need...
i was change my code to:
public partial class Form1 : Form
{
List<Point> curPoints = new List<Point>();
List<List<Point>> allPoints = new List<List<Point>>();
public Form1()
{
InitializeComponent();
}
private void panel1_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button != MouseButtons.Left) return;
// here we should check if the distance is more than a minimum!
curPoints.Add(e.Location);
// let it show
panel1.Invalidate();
}
private void panel1_MouseUp(object sender, MouseEventArgs e)
{
if (curPoints.Count > 1)
{
// ToList creates a copy
allPoints.Add(curPoints.ToList());
curPoints.Clear();
}
}
private void panel1_MouseDown(object sender, MouseEventArgs e)
{
if (curPoints.Count > 1)
{
// begin fresh line or curve
curPoints.Clear();
// startpoint
curPoints.Add(e.Location);
}
}
private void panel1_Paint(object sender, PaintEventArgs e)
{
// here you can use DrawLines or DrawCurve
// current line
if (curPoints.Count > 1) e.Graphics.DrawCurve(Pens.Red, curPoints.ToArray());
// other lines or curves
foreach (List<Point> points in allPoints)
if (points.Count > 1) e.Graphics.DrawCurve(Pens.Red, points.ToArray());
}
}
But nothing better. The result is worse...
I tried to write: "Hello my name is Hieu", but is not run...
Looks like a pen-tablet differs from a mouse when use to write. Because, with mouse i feel that is better in this code...
UPDATE 2:
With code by Idle_Mind. It will be fine if i set pen-tablet:
With setting "Click", it is not OK
How to fix it, i don't want to set "Double Click" to my pen !
Here's my version...worked great for me. You might need to adjust your tablet settings so that it picks up everything correctly:
public partial class FormTablet : Form
{
private Point lastPoint;
private GraphicsPath GP = null;
private List<GraphicsPath> GPs = new List<GraphicsPath>();
public FormTablet()
{
InitializeComponent();
}
private void checkBox1_CheckedChanged(object sender, EventArgs e)
{
pictureBox1.Invalidate();
}
private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
lastPoint = new Point(e.X, e.Y);
GP = new GraphicsPath();
GP.AddLine(lastPoint, lastPoint);
GPs.Add(GP);
}
}
private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
Point pt = new Point(e.X, e.Y);
GP.AddLine(lastPoint, pt);
lastPoint = pt;
pictureBox1.Invalidate();
}
}
private void pictureBox1_MouseUp(object sender, MouseEventArgs e)
{
GP = null;
pictureBox1.Invalidate();
}
private void pictureBox1_Paint(object sender, PaintEventArgs e)
{
if (checkBox1.Checked)
{
e.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
}
using(Pen p = new Pen(Color.Black, (int)numericUpDown1.Value))
{
p.LineJoin = LineJoin.Round;
p.MiterLimit = p.Width / 2;
foreach (GraphicsPath path in GPs)
{
if (path.PathPoints.Count() > 2)
{
// draw the path
e.Graphics.DrawPath(p, path);
}
else
{
// just draw a single dot
Rectangle rc = new Rectangle(Point.Round(path.PathPoints[0]), new Size(1, 1));
rc.Inflate((int)numericUpDown1.Value, (int)numericUpDown1.Value);
e.Graphics.FillEllipse(Brushes.Black, rc);
}
}
}
}
private void numericUpDown1_ValueChanged(object sender, EventArgs e)
{
pictureBox1.Invalidate();
}
private void button1_Click(object sender, EventArgs e)
{
GPs.Clear();
pictureBox1.Invalidate();
}
}
IDE: visual studio, c#, Windows from application
I am trying to draw a line on a panel. I am able to draw line on panel1 by clicking on it.
//Code
public partial class Form1 : Form
{
static int px=5, py=5;
public Form1()
{
InitializeComponent();
}
private void panel1_Paint(object sender, PaintEventArgs e)
{
e.Graphics.DrawLine(Pens.Red, 5, 5, px, py);
}
private void panel1_MouseDown(object sender, MouseEventArgs e)
{
initilizeXY(e.X, e.Y);
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void panel1_MouseMove(object sender, MouseEventArgs e)
{
}
private void initilizeXY( int pxx, int pyy)
{
px = pxx;
py = pyy;
}
private void panel1_MouseUp(object sender, MouseEventArgs e)
{
panel1.Refresh();
}
private void panel2_MouseDown(object sender, MouseEventArgs e)
{
initilizeXY(e.X, e.Y);
}
}
// by this code i am able to draw a line on mouse down on panel 1.
but due to some requirement changes there is another panel ( panel2) which is partially overlapping panel1.
Now i want to draw the same line on panel1 if the user click on panel1 or panel2.
Please suggest how make this work done?
This code works:
Point bgn1 = new Point(5, 5);
Point end1 = new Point(5, 5);
Point bgn2 = new Point(0, 0);
Point end2 = new Point(0, 0);
private void Form1_Load(object sender, EventArgs e)
{
Point pnt, pntscr;
pnt.X = 5;
pnt.Y = 5;
pntscr = Panel1.PointToScreen(pnt);
bgn2 = Panel2.PointToClient(pntscr);
end2 = bgn2;
}
private void panel1_MouseDown(object sender, MouseEventArgs e)
{
end1.X = e.X;
end1.Y = e.Y;
Point pntscr;
pntscr = Panel1.PointToScreen(end1);
end2 = Panel2.PointToClient(pntscr);
}
private void panel1_MouseUp(object sender, MouseEventArgs e)
{
panel1.Refresh();
panel2.Refresh();
}
private void panel2_MouseDown(object sender, MouseEventArgs e)
{
end2.X = e.X;
end2.Y = e.Y;
Point pntscr;
pntscr = Panel2.PointToScreen(end2);
end1 = Panel1.PointToClient(pntscr);
}
private void panel2_MouseUp(object sender, MouseEventArgs e)
{
panel1.Refresh();
panel2.Refresh();
}
private void panel1_Paint(object sender, PaintEventArgs e)
{
e.Graphics.DrawLine(Pens.Red, bgn1, end1);
}
private void panel2_Paint(object sender, PaintEventArgs e)
{
e.Graphics.DrawLine(Pens.Red, bgn2, end2);
}
valter
EDIT: Fixed the code to work properly.
Tested in a scenario when panel2 overlaps panel1 on the right side of panel1, starting a little lower than panel1's top.
Writing this bit of code I assumed panel2's X and Y coords are greater than panel1's. Perhaps you should reverse the offset calculation if it's the other way around.
public partial class Form1 : Form
{
static int px = 5, py = 5;
static int p2x = 0, p2y = 0;
int offsetX;
int offsetY;
public Form1()
{
InitializeComponent();
offsetX = panel2.Location.X - panel1.Location.X;
offsetY = panel2.Location.Y - panel1.Location.Y;
}
private void panel1_Paint(object sender, PaintEventArgs e)
{
e.Graphics.DrawLine(Pens.Red, 5, 5, px, py);
}
private void panel1_MouseDown(object sender, MouseEventArgs e)
{
initilizeXY(e.X, e.Y);
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void initilizeXY(int pxx, int pyy)
{
px = pxx;
py = pyy;
}
private void initilizeXY2(int pxx, int pyy)
{
p2x = pxx;
p2y = pyy;
}
private void panel1_MouseUp(object sender, MouseEventArgs e)
{
panel1.Refresh();
panel2.Refresh();
}
private void panel2_MouseDown(object sender, MouseEventArgs e)
{
initilizeXY(e.X+offsetX, e.Y+offsetY);
initilizeXY2(e.X, e.Y);
}
private void panel2_Paint(object sender, PaintEventArgs e)
{
if (px > offsetX && py > offsetY)
{
int p2start = findIntersectFromLineEquation(new Point(5, 5), new Point(px, py));
e.Graphics.DrawLine(Pens.Red, 0, p2start - offsetY, p2x, p2y);
}
}
private int findIntersectFromLineEquation(Point start, Point end)
{
if (start.X == end.X || start.Y == end.Y)
return 0;
double a = (double)(end.Y - start.Y) / (double)(end.X - start.X);
double b = (double)(start.Y) - (double)(a * start.X);
return (int)(a * offsetX + b);
}
}
Remember to subscribe the events accordingly.
When mouse move over a panel2, I need to draw lines. So far I have done following
public Form1()
{
InitializeComponent();
}
private void panel2_Paint(object sender, PaintEventArgs e)
{
if (isDragging)
{
letsPaint(sender, e);
}
}
private void panel2_MouseMove(object sender, MouseEventArgs e)
{
if (isDragging)
{
mouseMoveX = e.X;
mouseMoveY = e.Y;
this.Paint += new PaintEventHandler(panel2_Paint);
}
}
private void letsPaint(object sender, PaintEventArgs e)
{
Pen blackpen = new Pen(Color.Black, 3);
Graphics g = e.Graphics;
g.DrawLine(blackpen, mouseClickedX, mouseClickedY, mouseMoveX, mouseMoveY);
g.Dispose();
}
But nothing happens when I move mouse. I think I did something wrong PaintEventHandler() here. Please tell me how to do this and also if there is any better way for this.
Also I think my method will drawline on the form but I need to draw line on the panel2. How to do? Thanks in advance.
You invalidate:
public Form1()
{
InitializeComponent();
panel2.Paint += new letsPaint;
}
private void panel2_MouseMove(object sender, MouseEventArgs e)
{
if (isDragging) {
mouseMoveX = e.X;
mouseMoveY = e.Y;
panel2.Invalidate();
}
}
and you don't dispose the graphic object (you didn't create it), but you do the pen:
private void letsPaint(object sender, PaintEventArgs e) {
using (Pen blackpen = new Pen(Color.Black, 3)) {
e.Graphics.DrawLine(blackpen,
mouseClickedX, mouseClickedY, mouseMoveX, mouseMoveY);
}
}
Here is a quick little method that works with a bitmap:
Bitmap bmp;
Point lastPoint;
public Form1() {
InitializeComponent();
bmp = new Bitmap(panel1.ClientSize.Width, panel1.ClientSize.Height,
System.Drawing.Imaging.PixelFormat.Format32bppPArgb);
panel1.MouseDown += panel1_MouseDown;
panel1.MouseMove += panel1_MouseMove;
panel1.Paint += panel1_Paint;
}
void panel1_Paint(object sender, PaintEventArgs e) {
e.Graphics.DrawImage(bmp, Point.Empty);
}
void panel1_MouseMove(object sender, MouseEventArgs e) {
if (e.Button == MouseButtons.Left) {
using (Graphics g = Graphics.FromImage(bmp)) {
g.DrawLine(Pens.Black, lastPoint, e.Location);
}
lastPoint = e.Location;
panel1.Invalidate();
}
}
void panel1_MouseDown(object sender, MouseEventArgs e) {
lastPoint = e.Location;
}
This will flicker, so you would want to replace your panel with a double-buffered panel. Something like this:
public class PanelEx : Panel {
public PanelEx() {
this.DoubleBuffered = true;
}
}
I just want to draw an ellipse dynamically when running . mouseclick then mousemove and then mouse release that's it . But, confused of detecting point(x,y).Can someone help me out of this
You basically just need to record the starting point from the MouseDown event, so that you can make the ellipse with the point recorded from the MouseUp event.
Simple demo:
public partial class Form1 : Form {
private Point _StartPoint;
private List<Rectangle> _Ovals = new List<Rectangle>();
public Form1() {
InitializeComponent();
this.MouseDown += new MouseEventHandler(Form1_MouseDown);
this.MouseUp += new MouseEventHandler(Form1_MouseUp);
this.Paint += new PaintEventHandler(Form1_Paint);
}
void Form1_Paint(object sender, PaintEventArgs e) {
foreach (Rectangle r in _Ovals)
e.Graphics.FillEllipse(Brushes.Red, r);
}
void Form1_MouseDown(object sender, MouseEventArgs e) {
if (e.Button == MouseButtons.Left)
_StartPoint = e.Location;
}
void Form1_MouseUp(object sender, MouseEventArgs e) {
if (e.Button == MouseButtons.Left) {
_Ovals.Add(MakeRectangle(_StartPoint, e.Location));
this.Invalidate();
}
}
private Rectangle MakeRectangle(Point p1, Point p2) {
int x = (p1.X < p2.X ? p1.X : p2.X);
int y = (p1.Y < p2.Y ? p1.Y : p2.Y);
int w = Math.Abs(p1.X - p2.X);
int h = Math.Abs(p1.Y - p2.Y);
return new Rectangle(x, y, w, h);
}
}
Any suggestions how to create a line by clicking two new points then draw a line between them?
I am trying to create a distance tool like the one in adobe acrobat.
Image Example
Problem Solved!
EDIT:
Here's the code:
private Point p1, p2;
List<Point> p1List = new List<Point>();
List<Point> p2List = new List<Point>();
private void Panel1_MouseDown(object sender, MouseEventArgs e)
{
if (p1.X == 0)
{
p1.X = e.X;
p1.Y = e.Y;
}
else
{
p2.X = e.X;
p2.Y = e.Y;
p1List.Add(p1);
p2List.Add(p2);
Invalidate();
p1.X = 0;
}
}
private void Panel1_Paint(object sender, PaintEventArgs e)
{
using(var p = new Pen(Color.Blue, 4))
{
for(int x = 0; x<p1List.Count; x++){
e.Graphics.DrawLine(p, p1List[x], p2List[x]);
}
}
}
You can handle the mouse click event on the panel (for example) and retrieve the location of the click (using the event args). Store this location in an attribute. Do that for as many points as you need.
In the panel paint event, call the parent paint, then draw the lines between your points.
Something like this should do it:
Point firstPoint;
Point seondPoint;
private void panel1_MouseDown(object sender, MouseEventArgs e)
{
if (this.firstPoint == null) {
this.firstPoint = e.Location;
}
if (this.secondPoint == null) {
this.secondPoint = e.Location;
}
panel1.Invalidate();
}
private void panel1_Paint_1(object sender, PaintEventArgs e)
{
Using (pn as new Pen(Color.Blue, 5))
{
e.Graphics.DrawLine(pn, firstPoint, secondPoint);
}
}
EDIT: You also dont need to do CreateGraphics to draw the line - in the Paint event you have a graphics object already.