Hi Folks,
Just a bit of background before the problem to give you an idea of where i'm coming from...
Programming experience:~ Bit of VBA (Excel & Access) & Bit of VB(2010). Mechanical design engineer in Solidworks,.
Proud owner of a Mini Scamp MK2 kit car, which my daughter has nicknamed 'Wall-e' (He's small, square & battered, like Wall-e.
Last year swapped the tired mini engine out for a Vauxhall astra 1.4 engine....thus the start of the dashboard instruments problems.
The plan.....Raspberry Pi, 12" touchscreen, some hardware interface, some graphical stuff & wahaay an electronic Dashboard....
Step 1...
Creating the graphical interface. Tool of choice, Solidworks....3d model the screen up & then render out to 8-bit png file.
Import the png file into a BGRALayeredBitmap to create the overlay bit. Then create layers for the static text & 'moving' bits.
Temporarily put a slider onto the form to set the position of the fuel gauge.
All working so far.....until...
I can move the position of the slider to any position & it updates & draws fine.
Move it a second time to any position & it's still fine.
Move it the third time & it's still fine.
Move the slider the fourth time & the display goes weird.
Move it a fifth time & i get a "raised exception class error.
See attached jpg for some idea of whats displaying.
unit MainDash001;
{$mode objfpc}{$H+}
interface
uses
Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, ComCtrls,
BGRALayers, BGRABitmap, BGRABitmapTypes, RTTICtrls;
type
{ TForm1 }
TForm1 = class(TForm)
Track1: TTrackBar;
TrackBar1: TTrackBar;
procedure FormCreate(Sender: TObject);
procedure FormPaint(Sender: TObject);
procedure TrackBar1Click(Sender: TObject);
private
ImageS: TBGRABitmap; //stretched master image
image: TBGRABitmap;
layers: TBGRALayeredBitmap; //original master image
layersStretch: TBGRALayeredBitmap;
StaticYel: TBGRABitmap;
TempYel: TBGRABitmap;
FuelYel: TBGRABitmap;
RevYel: TBGRABitmap;
SpeedYel: TBGRABitmap;
TempBtm,TempTop, TempL, TempR,TempVal: integer;
T1,T2,T3,T4,T5,T6,T7: integer;
procedure PaintImage;
public
{ public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.lfm}
{ TForm1 }
procedure TForm1.FormCreate(Sender: TObject);
begin
//Create Top Overlay Layer with main png file (8-bit)
layers:= TBGRALayeredBitmap.Create(1280,800);
layers.AddLayerFromFile('Dash-003-Background.png');
layers.LayerOpacity[layers.AddLayerFromFile('Dash-003-Background.png')]:=255;
//Create layer for the static yellow bits
StaticYel:= TBGRABitmap.Create(1280,800);
StaticYel.FillRect(360,280,650,710,BGRA(245,255,120,255),dmset);
StaticYel.FillRect(1010,250,1240,310,BGRA(245,255,120,255),dmset);
StaticYel.FillRect(1010,250,1082,380,BGRA(245,255,120,255),dmset);
StaticYel.FillRect(1010,536,1082,632,BGRA(245,255,120,255),dmXor);
StaticYel.FillRect(1050,730,1245,764,BGRA(245,255,120,255),dmXor);
layers.AddOwnedLayer(StaticYel);
layers.MoveLayerDown(2); //move layer down so it displays under the main png layer
//Create layer for temperature gauge
TempYel:= TBGRABitmap.Create(1280,800);
layers.AddOwnedLayer(TempYel);
layers.MoveLayerDown(3); //move layer down so it displays under the main png layer
layers.Resample(1280,800, rmfineresample); //resample the lot to display at 1280x800 res
PaintImage;
end;
procedure TForm1.FormPaint(Sender: TObject);
var i: integer ;
begin
PaintImage;
end;
//Use slider to replicate the sensing calculations & stuff
procedure TForm1.TrackBar1Click(Sender: TObject);
begin //Assign variable for height of yellow rectangle
TempL:=1080;
TempR:=1250;
TempBtm:=712;
T1:=698;
T2:=682;
T3:=665;
T4:=640;
T5:=610;
T6:=575;
T7:=500;
if trackbar1.Position = 0 then //based on slider position assign a height for rectangle
begin
TempTop := TempBtm+1
end;
if trackbar1.Position = 1 then
begin
TempTop:=T1
end;
if Trackbar1.Position = 2 then
begin
TempTop:=T2
end;
if Trackbar1.Position = 3 then
begin
TempTop:=T3
end;
if Trackbar1.Position = 4 then
begin
TempTop:=T4
end;
if Trackbar1.Position = 5 then
begin
TempTop:=T5
end;
if Trackbar1.Position = 6 then
begin
TempTop:=T6
end;
if Trackbar1.Position = 7 then
begin
TempTop:=T7
end; //draw a rectangle with background colour to cover old yellow rectangle
TempYel.FillRect(TempL,400,TempR,TempBtm,BGRA(73,73,74,255),dmset);
//draw the new yellow rectangle at the height chosen on the slider
TempYel.FillRect(TempL,TempTop,TempR,TempBtm,BGRA(245,255,120,255),dmset);
PaintImage;
end;
procedure TForm1.PaintImage;
begin
layers.Resample(1280,800, rmfineresample);
layers.Draw(Canvas,0,0);
end;
end.If i've not posted in the right way or done something wrong, apols,
it's my 1st post...please don't flame me.
Apologies for my programming in advance, any hints & tips would be appreciated. (Any criticism is constructive)
Thanx in advance,
Neil
Recent
