Vesa32 additions + util functions to support

src/driver/video/vesa32.pas

@@ -35,11 +35,11 @@ var
     LocationIndex : Uint32;
 
 begin
-    tracer.push_trace('vesa32.DrawPixel.enter');
+    //tracer.push_trace('vesa32.DrawPixel.enter');
     Location:= Puint32(Buffer^.Location);
     LocationIndex:= (Y * Buffer^.Width) + X;
     Location[LocationIndex]:= uint32(Pixel);
-    tracer.push_trace('vesa32.DrawPixel.exit');
+    //tracer.push_trace('vesa32.DrawPixel.exit');
 end;
 
 procedure init(DrawRoutines : PDrawRoutines);

src/driver/video/videotypes.pas

@@ -25,7 +25,7 @@ uses
     color;
 
 type
-    //Arbitrary pointer to a video buffer in memory
+    //Arbitrary pointer to a raw video buffer in memory
     VideoBuffer = uint32;
 
     //Struct representing a Memory Mapped Video Buffer
@@ -48,11 +48,20 @@ type
     FDrawPixel = procedure(Buffer : PVideoBuffer; X : uint32; Y : uint32; Pixel : TRGB32);
     //(Abstract) Flush backbuffer to MMIO Buffer
     FFlush     = procedure(FrontBuffer : PVideoBuffer; BackBuffer : PVideoBuffer);
+    //(Abstract) Draw a line to the screen
+    FDrawLine = procedure(Buffer : PVideoBuffer; x1,y1,x2,y2 : uint32; thickness : uint32; Color : TRGB32);
+    //(Abstract) Draw a rect to the screen
+    FDrawRect = procedure(Buffer : PVideoBuffer; x1,y1,x2,y2 : uint32; line_thickness : uint32; Color : TRGB32);
+    //(Abstract) Draw a filled rect to the screen
+    FFillRect = procedure(Buffer : PVideoBuffer; x1,y1,x2,y2 : uint32; line_thickness : uint32; Line_Color : TRGB32; Fill_Color : TRGB32);
 
     //Routines for drawing to the screen
     TDrawRoutines = record
         DrawPixel : FDrawPixel;
         Flush     : FFlush;
+        DrawLine  : FDrawLine;
+        DrawRect  : FDrawRect;
+        FillRect  : FFillRect;
     end;
     //Pointer to drawing routines
     PDrawRoutines = ^TDrawRoutines;

src/include/util.pas

@@ -80,6 +80,8 @@ function RorDWord(AValue : uint32; Dist : uint8) : uint32;
 
 function MsSinceSystemBoot : uint64;
 
+function abs(x : sint32) : uint32;
+
 var
     endptr : uint32; external name '__end';
     stack  : uint32; external name 'KERNEL_STACK';
@@ -89,6 +91,15 @@ implementation
 uses
     console, RTC, cpu, serial, strings, isr_types;
 
+function abs(x : sint32) : uint32;
+var
+    y : uint32;
+
+begin
+    y:= x SHR 31;
+    abs:= (x XOR y) - y;
+end;
+
 function MsSinceSystemBoot : uint64;
 begin
     MsSinceSystemBoot:= div6432(getTSC, (CPUID.ClockSpeed.Hz div 1000));

src/kernel.pas

@@ -211,23 +211,21 @@ begin
      doublebuffer.init(@video.register);
      video.enable('VESA');
      video.enable('BASIC_DOUBLE_BUFFER');
-     colour:= color.red;
+     colour:= color.white;
-     while true do begin
+
      for i:=0 to video.frontBufferWidth-1 do begin
         for z:=0 to video.frontBufferHeight-1 do begin
             video.DrawPixel(i, z, colour);
         end;
      end;
 
-        if uint32(colour) = uint32(color.red) then
+     video.DrawLine(50,50,100,100,1,color.black);
-            colour:= color.green
+     video.DrawRect(50,150,100,200,1,color.black);
-        else if uint32(colour) = uint32(color.green) then
+     video.FillRect(50,250,100,300,1,color.black,color.red);
-            colour:= color.blue
+     video.DrawLine(50,350,100,350,1,color.black);
-        else if uint32(colour) = uint32(color.blue) then
-            colour:= color.red;
-
      video.Flush();
-     end;
+
+     while true do begin end;
 
      { VFS Init }
      vfs.init();