ADD: Optional clear "old" points on start

Author: PascalCorpsman

miniprojects/Spirograph/project1.lpi

@@ -49,7 +49,7 @@
         <IsPartOfProject Value="True"/>
         <EditorIndex Value="-1"/>
         <CursorPos X="35" Y="5"/>
-        <UsageCount Value="43"/>
+        <UsageCount Value="44"/>
       </Unit0>
       <Unit1>
         <Filename Value="unit1.pas"/>
@@ -59,11 +59,11 @@
         <ResourceBaseClass Value="Form"/>
         <UnitName Value="Unit1"/>
         <IsVisibleTab Value="True"/>
-        <TopLine Value="268"/>
-        <CursorPos X="44" Y="288"/>
-        <UsageCount Value="43"/>
+        <TopLine Value="472"/>
+        <CursorPos X="15" Y="495"/>
+        <UsageCount Value="44"/>
         <Bookmarks Count="1">
-          <Item0 Y="356" ID="1"/>
+          <Item0 Y="503" ID="1"/>
         </Bookmarks>
         <Loaded Value="True"/>
         <LoadedDesigner Value="True"/>
@@ -102,7 +102,7 @@
         <EditorIndex Value="-1"/>
         <TopLine Value="2886"/>
         <CursorPos Y="2909"/>
-        <UsageCount Value="25"/>
+        <UsageCount Value="26"/>
       </Unit7>
       <Unit8>
         <Filename Value="/home/corpsman/lazarus/lcl/include/control.inc"/>
@@ -238,121 +238,130 @@
         <WindowIndex Value="-1"/>
         <TopLine Value="-1"/>
         <CursorPos X="-1" Y="-1"/>
-        <UsageCount Value="20"/>
+        <UsageCount Value="21"/>
       </Unit25>
     </Units>
-    <JumpHistory Count="28" HistoryIndex="27">
+    <JumpHistory Count="30" HistoryIndex="29">
       <Position1>
         <Filename Value="unit1.pas"/>
+        <Caret Line="281" Column="28" TopLine="274"/>
       </Position1>
       <Position2>
         <Filename Value="unit1.pas"/>
-        <Caret Line="309" TopLine="277"/>
+        <Caret Line="310" TopLine="308"/>
       </Position2>
       <Position3>
         <Filename Value="unit1.pas"/>
-        <Caret Line="224" Column="64" TopLine="213"/>
+        <Caret Line="315" Column="28" TopLine="308"/>
       </Position3>
       <Position4>
         <Filename Value="unit1.pas"/>
-        <Caret Line="275" Column="45" TopLine="268"/>
+        <Caret Line="316" Column="28" TopLine="309"/>
       </Position4>
       <Position5>
         <Filename Value="unit1.pas"/>
-        <Caret Line="273" Column="9" TopLine="258"/>
+        <Caret Line="353" Column="36" TopLine="328"/>
       </Position5>
       <Position6>
         <Filename Value="unit1.pas"/>
-        <Caret Line="288" Column="3" TopLine="258"/>
+        <Caret Line="304" Column="3" TopLine="262"/>
       </Position6>
       <Position7>
         <Filename Value="unit1.pas"/>
-        <Caret Line="117" Column="16" TopLine="95"/>
+        <Caret Line="305" Column="3" TopLine="270"/>
       </Position7>
       <Position8>
         <Filename Value="unit1.pas"/>
-        <Caret Line="446" Column="10" TopLine="419"/>
+        <Caret Line="306" Column="3" TopLine="271"/>
       </Position8>
       <Position9>
         <Filename Value="unit1.pas"/>
-        <Caret Line="118" Column="24" TopLine="94"/>
+        <Caret Line="307" Column="3" TopLine="272"/>
       </Position9>
       <Position10>
         <Filename Value="unit1.pas"/>
-        <Caret Line="443" TopLine="409"/>
+        <Caret Line="308" Column="3" TopLine="273"/>
       </Position10>
       <Position11>
         <Filename Value="unit1.pas"/>
-        <Caret Line="115" Column="15" TopLine="93"/>
+        <Caret Line="335" Column="5" TopLine="334"/>
       </Position11>
       <Position12>
         <Filename Value="unit1.pas"/>
-        <Caret Line="421" Column="37" TopLine="407"/>
+        <Caret Line="347" Column="21" TopLine="334"/>
       </Position12>
       <Position13>
         <Filename Value="unit1.pas"/>
-        <Caret Line="273" TopLine="271"/>
+        <Caret Line="284" Column="10" TopLine="268"/>
       </Position13>
       <Position14>
         <Filename Value="unit1.pas"/>
-        <Caret Line="278" Column="28" TopLine="271"/>
+        <Caret Line="274" Column="24" TopLine="268"/>
       </Position14>
       <Position15>
         <Filename Value="unit1.pas"/>
-        <Caret Line="279" Column="28" TopLine="272"/>
+        <Caret Line="275" Column="24" TopLine="269"/>
       </Position15>
       <Position16>
         <Filename Value="unit1.pas"/>
-        <Caret Line="281" Column="28" TopLine="274"/>
+        <Caret Line="263" Column="3" TopLine="261"/>
       </Position16>
       <Position17>
         <Filename Value="unit1.pas"/>
-        <Caret Line="310" TopLine="308"/>
+        <Caret Line="128" Column="16" TopLine="97"/>
       </Position17>
       <Position18>
         <Filename Value="unit1.pas"/>
-        <Caret Line="315" Column="28" TopLine="308"/>
+        <Caret Line="498" Column="18" TopLine="491"/>
       </Position18>
       <Position19>
         <Filename Value="unit1.pas"/>
-        <Caret Line="316" Column="28" TopLine="309"/>
+        <Caret Line="132" Column="16" TopLine="112"/>
       </Position19>
       <Position20>
         <Filename Value="unit1.pas"/>
-        <Caret Line="353" Column="36" TopLine="328"/>
+        <Caret Line="556" Column="18" TopLine="535"/>
       </Position20>
       <Position21>
         <Filename Value="unit1.pas"/>
-        <Caret Line="304" Column="3" TopLine="262"/>
+        <Caret Line="263" Column="3" TopLine="261"/>
       </Position21>
       <Position22>
         <Filename Value="unit1.pas"/>
-        <Caret Line="305" Column="3" TopLine="270"/>
+        <Caret Line="128" Column="16" TopLine="112"/>
       </Position22>
       <Position23>
         <Filename Value="unit1.pas"/>
-        <Caret Line="306" Column="3" TopLine="271"/>
+        <Caret Line="494" Column="20" TopLine="491"/>
       </Position23>
       <Position24>
         <Filename Value="unit1.pas"/>
-        <Caret Line="307" Column="3" TopLine="272"/>
+        <Caret Line="126" Column="13" TopLine="112"/>
       </Position24>
       <Position25>
         <Filename Value="unit1.pas"/>
-        <Caret Line="308" Column="3" TopLine="273"/>
+        <Caret Line="240" Column="19" TopLine="222"/>
       </Position25>
       <Position26>
         <Filename Value="unit1.pas"/>
-        <Caret Line="335" Column="5" TopLine="334"/>
+        <Caret Line="133" Column="18" TopLine="115"/>
       </Position26>
       <Position27>
         <Filename Value="unit1.pas"/>
-        <Caret Line="347" Column="21" TopLine="334"/>
+        <Caret Line="561" Column="31" TopLine="479"/>
       </Position27>
       <Position28>
         <Filename Value="unit1.pas"/>
-        <Caret Line="284" Column="10" TopLine="268"/>
+        <Caret Line="200" Column="3" TopLine="198"/>
       </Position28>
+      <Position29>
+        <Filename Value="unit1.pas"/>
+        <Caret Line="128" Column="16" TopLine="112"/>
+      </Position29>
+      <Position30>
+        <Filename Value="unit1.pas"/>
+        <Caret Line="494" Column="31" TopLine="470"/>
+      </Position30>
     </JumpHistory>
   </ProjectOptions>
   <CompilerOptions>

miniprojects/Spirograph/unit1.lfm

@@ -195,6 +195,16 @@ object Form1: TForm1
     TabOrder = 12
     OnClick = Button10Click
   end
+  object CheckBox2: TCheckBox
+    Left = 144
+    Height = 22
+    Top = 8
+    Width = 105
+    Caption = 'Clear on start'
+    Checked = True
+    State = cbChecked
+    TabOrder = 13
+  end
   object Timer1: TTimer
     OnTimer = Timer1Timer
     Left = 312

miniprojects/Spirograph/unit1.pas

@@ -85,6 +85,7 @@
     Button8: TButton;
     Button9: TButton;
     CheckBox1: TCheckBox;
+    CheckBox2: TCheckBox;
     CheckBox3: TCheckBox;
     Edit1: TEdit;
     Edit2: TEdit;
@@ -122,6 +123,7 @@
     Spiral: TSpirals;
     State: TState;
     pts: Tpts; // Leider funktioniert der Accumulationbuffer von OpenGL nicht mit OpenGlControl -> Also muss das von Hand nachgebildet werden.
+    ptsStack: Array Of TPTS;
     StartTime, LastRenderTime: QWord;
     Procedure RenderScene();
     Procedure StartSim;
@@ -235,6 +237,7 @@
   Spiral := Nil;
   State := sIdle;
   pts := Nil;
+  ptsStack := Nil;
   edit1.text := '50';
   edit2.text := '1';
   Button6.Click;
@@ -415,7 +418,7 @@
 
 Procedure TForm1.RenderScene;
 Var
-  i: Integer;
+  i, j: Integer;
   n: QWord;
   d: Extended;
   m: TMatrix4x4;
@@ -458,7 +461,6 @@
     pts[high(pts)] := v2(m[3, 0], m[3, 1]);
   End;
   glPopMatrix;
-
   // Render der Linien falls gewünscht
   If CheckBox1.Checked Then Begin
     glPushMatrix;
@@ -474,7 +476,6 @@
     End;
     glPopMatrix;
   End;
-  //  If State = sSimulate Then Begin
   glPushMatrix;
   glTranslatef(-OpenGLControl1.Width / 2, -OpenGLControl1.Height / 2, 0);
   glColor3f(1, 1, 1);
@@ -483,21 +484,23 @@
     glVertex2fv(@pts[i]);
   End;
   glend;
+  For j := 0 To high(ptsStack) Do Begin
+    glColor3f(1, 1, 1);
+    glBegin(GL_LINE_STRIP);
+    For i := 0 To high(ptsStack[j]) Do Begin
+      glVertex2fv(@ptsStack[j, i]);
+    End;
+    glend;
+  End;
   glPopMatrix;
-  //  End;
 End;
 
 Procedure TForm1.StartSim;
-Var
-  i: Integer;
 Begin
   State := sSimulate;
   LastRenderTime := GetTickCount64;
   StartTime := LastRenderTime;
-  setlength(pts, 0);
-  For i := 0 To high(Spiral) Do Begin
-    Spiral[i].Rotation := 0;
-  End;
+  Reset;
 End;
 
 Procedure TForm1.AddLCLElement;
@@ -554,6 +557,15 @@
 Var
   i: Integer;
 Begin
+  If CheckBox2.Checked Then Begin
+    setlength(ptsStack, 0);
+  End
+  Else Begin
+    setlength(ptsStack, high(ptsStack) + 2);
+    setlength(ptsStack[high(ptsStack)], length(pts));
+    For i := 0 To high(pts) Do
+      ptsStack[high(ptsStack)][i] := pts[i];
+  End;
   setlength(pts, 0);
   For i := 0 To high(Spiral) Do Begin
     Spiral[i].Rotation := 0;