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// Geometric Tools, LLC
// Copyright (c) 1998-2014
// Distributed under the Boost Software License, Version 1.0.
// http://www.boost.org/LICENSE_1_0.txt
// http://www.geometrictools.com/License/Boost/LICENSE_1_0.txt
//
// File Version: 5.0.0 (2010/01/01)
#include "QuadraticFreeForm2D.h"
WM5_WINDOW_APPLICATION(QuadraticFreeForm2D);
//----------------------------------------------------------------------------
QuadraticFreeForm2D::QuadraticFreeForm2D ()
:
WindowApplication2("SampleMathematics/QuadraticFreeForm2D", 0, 0, 512,
512, Float4(1.0f, 1.0f, 1.0f, 1.0f))
{
mTexture = 0;
mMouseDown = false;
mRow = -1;
mCol = -1;
mSize = GetWidth();
}
//----------------------------------------------------------------------------
bool QuadraticFreeForm2D::OnInitialize ()
{
if (!WindowApplication2::OnInitialize())
{
return false;
}
// The texture whose image will be drawn on the quadrilateral.
std::string path = Environment::GetPathR("Magician.wmtf");
mTexture = Texture2D::LoadWMTF(path);
// The default control points produce the identity function.
int x = mSize/4, y = mSize/4;
mCtrlX[0][0] = x; mCtrlY[0][0] = y;
mCtrlX[0][1] = x; mCtrlY[0][1] = 2*y;
mCtrlX[0][2] = x; mCtrlY[0][2] = 3*y;
mCtrlX[1][0] = 2*x; mCtrlY[1][0] = y;
mCtrlX[1][1] = 2*x; mCtrlY[1][1] = 2*y;
mCtrlX[1][2] = 2*x; mCtrlY[1][2] = 3*y;
mCtrlX[2][0] = 3*x; mCtrlY[2][0] = y;
mCtrlX[2][1] = 3*x; mCtrlY[2][1] = 2*y;
mCtrlX[2][2] = 3*x; mCtrlY[2][2] = 3*y;
mCtrl[0][0] = Vector2f(0.0f, 0.0f);
mCtrl[0][1] = Vector2f(0.0f, 0.5f);
mCtrl[0][2] = Vector2f(0.0f, 1.0f);
mCtrl[1][0] = Vector2f(0.5f, 0.0f);
mCtrl[1][1] = Vector2f(0.5f, 0.5f);
mCtrl[1][2] = Vector2f(0.5f, 1.0f);
mCtrl[2][0] = Vector2f(1.0f, 0.0f);
mCtrl[2][1] = Vector2f(1.0f, 0.5f);
mCtrl[2][2] = Vector2f(1.0f, 1.0f);
DoFlip(true);
OnDisplay();
return true;
}
//----------------------------------------------------------------------------
void QuadraticFreeForm2D::OnTerminate ()
{
delete0(mTexture);
WindowApplication2::OnTerminate();
}
//----------------------------------------------------------------------------
void QuadraticFreeForm2D::OnDisplay ()
{
ClearScreen();
int dim0 = mTexture->GetDimension(0, 0);
int dim1 = mTexture->GetDimension(1, 0);
unsigned char* data = (unsigned char*)mTexture->GetData(0);
const int numSamples = 2*mSize;
const float invNumSamples = 1.0f/(float)numSamples;
Vector2f param;
for (int s = 0; s < numSamples; ++s)
{
int u = s*dim0/numSamples;
param.X() = invNumSamples*s;
for (int t = 0; t < numSamples; ++t)
{
int v = t*dim1/numSamples;
param.Y() = invNumSamples*t;
Vector2f result = Evaluate(param);
int x = ControlToScreen(result.X());
int y = ControlToScreen(result.Y());
int index = 4*(u + dim0*v);
unsigned char b = data[index++];
unsigned char g = data[index++];
unsigned char r = data[index++];
++index;
SetPixel(x, y, ColorRGB(r, g, b));
}
}
// Draw the control points.
ColorRGB green(0, 255, 0);
for (int row = 0; row <= 2; ++row)
{
for (int col = 0; col <= 2; ++col)
{
SetThickPixel(mCtrlX[row][col], mCtrlY[row][col], 2, green);
}
}
WindowApplication2::OnDisplay();
}
//----------------------------------------------------------------------------
bool QuadraticFreeForm2D::OnMouseClick (int button, int state, int x, int y,
unsigned int)
{
if (button != MOUSE_LEFT_BUTTON)
{
return false;
}
// Handle the flip in y that is used for drawing.
y = mSize - 1 - y;
if (state == MOUSE_DOWN)
{
mMouseDown = true;
SelectVertex(x, y);
return true;
}
if (state == MOUSE_UP)
{
mMouseDown = false;
if (mRow >= 0 && mCol >= 0
&& 0 <= x && x < GetWidth() && 0 <= y && y < GetHeight())
{
mCtrlX[mRow][mCol] = x;
mCtrlY[mRow][mCol] = y;
mCtrl[mRow][mCol].X() = ScreenToControl(x);
mCtrl[mRow][mCol].Y() = ScreenToControl(y);
OnDisplay();
}
return true;
}
return false;
}
//----------------------------------------------------------------------------
bool QuadraticFreeForm2D::OnMotion (int, int x, int y, unsigned int)
{
if (mMouseDown)
{
// Handle the flip in y that is used for drawing.
y = mSize - 1 - y;
if (mRow >= 0 && mCol >= 0
&& 0 <= x && x < GetWidth() && 0 <= y && y < GetHeight())
{
mCtrlX[mRow][mCol] = x;
mCtrlY[mRow][mCol] = y;
mCtrl[mRow][mCol].X() = ScreenToControl(x);
mCtrl[mRow][mCol].Y() = ScreenToControl(y);
OnDisplay();
}
return true;
}
return false;
}
//----------------------------------------------------------------------------
float QuadraticFreeForm2D::ScreenToControl (int screen) const
{
return 2*screen/(float)mSize - 0.5f;
}
//----------------------------------------------------------------------------
int QuadraticFreeForm2D::ControlToScreen (float control) const
{
return (int)(mSize*(0.5f*control + 0.25f));
}
//----------------------------------------------------------------------------
Vector2f QuadraticFreeForm2D::Evaluate (const Vector2f& param) const
{
float s = param.X();
float t = param.Y();
float omS = 1.0f - s;
float omT = 1.0f - t;
float b0s = omS*omS;
float b0t = omT*omT;
float b1s = 2.0f*omS*s;
float b1t = 2.0f*omT*t;
float b2s = s*s;
float b2t = t*t;
Vector2f result =
b0s*(b0t*mCtrl[0][0] + b1t*mCtrl[0][1] + b2t*mCtrl[0][2]) +
b1s*(b0t*mCtrl[1][0] + b1t*mCtrl[1][1] + b2t*mCtrl[1][2]) +
b2s*(b0t*mCtrl[2][0] + b1t*mCtrl[2][1] + b2t*mCtrl[2][2]);
return result;
}
//----------------------------------------------------------------------------
void QuadraticFreeForm2D::SelectVertex (int x, int y)
{
// Identify vertex within 5 pixels of mouse click.
const int pixelRange = 5;
mRow = -1;
mCol = -1;
for (int row = 0; row <= 2; ++row)
{
for (int col = 0; col <= 2; ++col)
{
int dx = x - mCtrlX[row][col];
int dy = y - mCtrlY[row][col];
if (abs(dx) <= pixelRange && abs(dy) <= pixelRange)
{
mRow = row;
mCol = col;
return;
}
}
}
}
//----------------------------------------------------------------------------
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