//---------------------------------------------------------------------------

#include <vcl.h>
#pragma hdrstop

#include "fFormulaC.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma link "GLS.BaseClasses"
#pragma link "GLS.Coordinates"

#pragma link "GLS.Mesh"
#pragma link "GLS.Objects"
#pragma link "GLS.Scene"
#pragma link "GLS.SceneViewer"
#pragma resource "*.dfm"
TForm1* Form1;

const int
    // half-grid resolution, grid width is actually cResolution*2 of "quads"
    cResolution = 50;

//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner) : TForm(Owner) {}
//---------------------------------------------------------------------------

TAffineVector __fastcall TForm1::MakeVect(const float aX, const float aY)
{
	TAffineVector Result;
	SetVector(
		Result, aX * invRes1, sin((aX * aX + aY * aY) * invRes2), aY * invRes1);
	return Result;
}

//---------------------------------------------------------------------------

void __fastcall TForm1::AddTriangle(const TAffineVector p1,
	const TAffineVector p2, const TAffineVector p3, const TGLColorVector color)
{
	Mesh1->Vertices->AddVertex(p1, NullVector, color);
	Mesh1->Vertices->AddVertex(p2, NullVector, color);
	Mesh1->Vertices->AddVertex(p3, NullVector, color);
}

//---------------------------------------------------------------------------

void __fastcall TForm1::FormCreate(TObject* Sender)
{
	int x, y;
	TAffineVector pTopLeft;
	TAffineVector pTopRight;
	TAffineVector pBottomRight;
	TAffineVector pBottomLeft;

	// scaling precalcs for our math func
	invRes1 = (float)10 / cResolution;
	invRes2 = 0.1 * sqrt(invRes1);
	//
	// Triangles
	//
	// this one is basic : we calculate the corner points for each grid quad and
	// add the two triangles that make it
	Mesh1->Mode = mmTriangles;
	Mesh1->Vertices->Clear();
	for (y = -cResolution; y < cResolution; y++)
		for (x = -cResolution; x < cResolution; x++) {
			pTopLeft = MakeVect(x, y + 1);
			pTopRight = MakeVect(x + 1, y + 1);
			pBottomRight = MakeVect(x + 1, y);
			pBottomLeft = MakeVect(x, y);
			// top left triangle
			AddTriangle(pBottomLeft, pTopLeft, pTopRight, clrBlue);
			// bottom right triangle
			AddTriangle(pTopRight, pBottomRight, pBottomLeft, clrBlue);
		}
	Mesh1->CalcNormals(fwCounterClockWise);
	//      Vertices->Locked = True;

	//
	// TriangleStrip
	//
	// Same as triangle, however trianglestrips are continuous, and to cover
	// the grid, "null" segments are used at both ends of a strip (to avoid a
	// visible triangle that would stretch for the full width of the grid).
	// Note : this can be avoided by reversing grid traversing direction (one line
	// from left to right, one from right to left, etc.)
	Mesh2->Mode = mmTriangleStrip;
	Mesh2->Vertices->Clear();
	for (y = -cResolution; y < cResolution; y++) {
		pTopLeft = MakeVect(-cResolution, y + 1);
		Mesh2->Vertices->AddVertex(pTopLeft, NullVector, clrBlue);
		Mesh2->Vertices->AddVertex(pTopLeft, NullVector, clrBlue);
		for (x = -cResolution; x < cResolution; x++) {
			pTopRight = MakeVect(x + 1, y + 1);
			pBottomLeft = MakeVect(x, y);
			Mesh2->Vertices->AddVertex(pBottomLeft, NullVector, clrBlue);
			Mesh2->Vertices->AddVertex(pTopRight, NullVector, clrBlue);
        }
        pBottomRight = MakeVect(cResolution + 1, y);
        Mesh2->Vertices->AddVertex(pBottomRight, NullVector, clrBlue);
        Mesh2->Vertices->AddVertex(pBottomRight, NullVector, clrBlue);
        Mesh2->CalcNormals(fwClockWise);
		//      Vertices->Locked = True;
	}
}
//---------------------------------------------------------------------------

void __fastcall TForm1::Timer1Timer(TObject* Sender)
{
    // nb of triangles in scene
    Caption = "Formula " +
              Format("%d Triangles",
                  ARRAYOFCONST((2 * (cResolution * 2) * (cResolution * 2))));
    // calculate & display triangles framerate
    // we render twice to get a fair FPS rating
    GLSceneViewer1->ResetPerformanceMonitor();
    GLSceneViewer1->Buffer->Render();
    GLSceneViewer1->Buffer->Render();
    Label1->Caption = Format("%.2f FPS (mmTriangles)",
        ARRAYOFCONST((GLSceneViewer1->FramesPerSecond())));

    // calculate & display trianglestrip framerate
    // we render twice to get a fair FPS rating
    GLSceneViewer2->ResetPerformanceMonitor();
    GLSceneViewer2->Buffer->Render();
    GLSceneViewer2->Buffer->Render();
    Label2->Caption = Format("%.2f FPS (mmTriangleStrip)",
        ARRAYOFCONST((GLSceneViewer2->FramesPerSecond())));
}
//---------------------------------------------------------------------------

void __fastcall TForm1::GLSceneViewer1MouseDown(
    TObject* Sender, TMouseButton Button, TShiftState Shift, int X, int Y)
{
	mx = X;
    my = Y;
}
//---------------------------------------------------------------------------

void __fastcall TForm1::GLSceneViewer1MouseMove(
	TObject* Sender, TShiftState Shift, int X, int Y)
{
    if (Shift.Contains(ssLeft)) {
        GLSceneViewer1->Camera->MoveAroundTarget(my - Y, mx - X);
        my = Y;
        mx = X;
    }
}
//---------------------------------------------------------------------------

void __fastcall TForm1::GLSceneViewer2MouseDown(
    TObject* Sender, TMouseButton Button, TShiftState Shift, int X, int Y)
{
    mx = X;
    my = Y;
}
//---------------------------------------------------------------------------

void __fastcall TForm1::GLSceneViewer2MouseMove(
    TObject* Sender, TShiftState Shift, int X, int Y)
{
    if (Shift.Contains(ssLeft)) {
        GLSceneViewer2->Camera->MoveAroundTarget(my - Y, mx - X);
        my = Y;
        mx = X;
    }
}
//---------------------------------------------------------------------------