util.cpp

/*
 * util.cpp
 *
 *  Created on: May 2, 2014
 *      Author: Sibt ul Hussain
 */
#include "util.h"
/*
 * This function converts an input angle from degree to radians */
float Deg2rad(float degree) {
	return (degree / 180.0) * M_PI;
}

// seed the random numbers generator by current time (see the documentation of srand for further help)...
void InitRandomizer() {
	srand((unsigned int) time(0)); // time(0) returns number of seconds elapsed since January 1, 1970.
}

//This function returns a random value within the specified range of [rmin, rmax] ...
long GetRandInRange(const long &rmin, const long &rmax) {
	long range = rmax - rmin; // find the range
	long value = (rand() % (long) range) + rmin; // translate the generated number ...
//	cout << value << endl << flush;
	return value;
}

/*To draw a triangle we need three vertices with each vertex having 2-coordinates [x, y] and a color for the triangle.
 * This function takes 4 arguments first three arguments (3 vertices + 1 color) to
 * draw the triangle with the given color.
 * */
void DrawTriangle(int x1, int y1, int x2, int y2, int x3, int y3,
		float color[]) {
	glColor3fv(color); // Set the triangle colour
	// ask library to draw triangle at given position...

	glBegin(GL_TRIANGLES);
	/*Draw triangle using given three vertices...*/
	glVertex4i(x1, y1, 0, 1);
	glVertex4i(x2, y2, 0, 1);
	glVertex4i(x3, y3, 0, 1);
	glEnd();
}


const int nvertices = 722;
GLfloat vertices[nvertices][2];
void InitCircleVertices(float radius) {

	float hdegree = M_PI / 360.0;
	float angle = 0;
	for (int i = 0; i < nvertices; ++i) {
		vertices[i][0] = radius * cos(angle);
		vertices[i][1] = radius * sin(angle);
		angle += hdegree;
	}
}

void DrawCircle(float sx, float sy, float radius, float*color) {

	glColor3fv(color); // set the circle color
	InitCircleVertices(radius);
	glBegin(GL_TRIANGLE_FAN);
	glVertex4f(sx, sy, 0, 1);
	for (int i = 0; i < nvertices; ++i)
		glVertex4f(sx + vertices[i][0], sy + vertices[i][1], 0, 1);
	//			glVertex4f(sx + mx - 1, sy + my - 1, 0, 1);
	glEnd();
}
// function used to draw curves...
void Torus2d(int x /*Starting position x*/, int y /*Starting position Y*/,
		float angle, // starting angle in degrees
		float length,           // length of arc in degrees, >0
		float radius,           // inner radius, >0
		float width,            // width of torus, >0
		unsigned int samples,   // number of circle samples, >=3
		float *color) {
	angle = Deg2rad(angle);
	length = Deg2rad(length);
	if (color) { // set color for the Torus
		glColor3fv(color);
	}
	if (samples < 3)
		samples = 3;
	const float outer = radius + width;
	glBegin(GL_QUAD_STRIP);
	for (unsigned int i = 0; i <= samples; ++i) {
		float a = angle + (i / (float) samples) * length;
		glVertex2f(x + radius * cos(a), y + radius * sin(a));
		glVertex2f(x + outer * cos(a), y + outer * sin(a));
	}
	glEnd();
}

// Draw lines between two points P1(x1,y1) and P2(x2,y2)
void DrawLine(int x1, int y1, int x2, int y2, int lwidth, float *color) {
	glLineWidth(lwidth);
	if (color)
		glColor3fv(color);
	glBegin(GL_LINES);
	glVertex3f(x1, y1, 0.0);
	glVertex3f(x2, y2, 0);
	glEnd();
}

// Function draws a string at given x,y coordinates
void DrawString(int x, int y, const string& score, float * color) {
	//  A pointer to a font style..
	//  Fonts supported by GLUT are: GLUT_BITMAP_8_BY_13,
	//  GLUT_BITMAP_9_BY_15, GLUT_BITMAP_TIMES_ROMAN_10,
	//  GLUT_BITMAP_TIMES_ROMAN_24, GLUT_BITMAP_HELVETICA_10,
	//  GLUT_BITMAP_HELVETICA_12, and GLUT_BITMAP_HELVETICA_18.
	GLvoid *font_style = GLUT_BITMAP_TIMES_ROMAN_24;
	if (color)
		glColor3fv(color);
	glRasterPos3f(x, y, 1);
	//  Draw the characters one by one
	for (int i = 0; i < score.size(); i++)
		glutBitmapCharacter(font_style, score[i]);
}

//
//  Draws rounded rectangle.
//
//  Slightly tuned version of http://stackoverflow.com/questions/5369507/opengles-1-0-2d-rounded-rectangle
//
#define ROUNDING_POINT_COUNT 16      // Larger values makes circle smoother.

typedef struct {
	float x;
	float y;

} Vector2f;
void DrawRoundRect(float x, float y, float width, float height, float* color,
		float radius) {
	y = y + height;
	Vector2f top_left[ROUNDING_POINT_COUNT];
	Vector2f bottom_left[ROUNDING_POINT_COUNT];
	Vector2f top_right[ROUNDING_POINT_COUNT];
	Vector2f bottom_right[ROUNDING_POINT_COUNT];

	if (radius == 0.0) {
		radius = min(width, height);
		radius *= 0.10; // 10%
	}

	int i = 0;
	float x_offset, y_offset;
	float step = (2.0f * M_PI) / (ROUNDING_POINT_COUNT * 4), angle = 0.0f;

	unsigned int index = 0, segment_count = ROUNDING_POINT_COUNT;
	Vector2f bottom_left_corner = { x + radius, y - height + radius };

	while (i != segment_count) {
		x_offset = cosf(angle);
		y_offset = sinf(angle);

		top_left[index].x = bottom_left_corner.x - (x_offset * radius);
		top_left[index].y = (height - (radius * 2.0f)) + bottom_left_corner.y
				- (y_offset * radius);

		top_right[index].x = (width - (radius * 2.0f)) + bottom_left_corner.x
				+ (x_offset * radius);
		top_right[index].y = (height - (radius * 2.0f)) + bottom_left_corner.y
				- (y_offset * radius);

		bottom_right[index].x = (width - (radius * 2.0f)) + bottom_left_corner.x
				+ (x_offset * radius);
		bottom_right[index].y = bottom_left_corner.y + (y_offset * radius);

		bottom_left[index].x = bottom_left_corner.x - (x_offset * radius);
		bottom_left[index].y = bottom_left_corner.y + (y_offset * radius);

	/*	top_left[index].x = top_left[index].x;
		top_left[index].y = top_left[index].y;

		top_right[index].x = top_right[index].x;
		top_right[index].y = top_right[index].y;

		bottom_right[index].x = bottom_right[index].x;
		bottom_right[index].y = bottom_right[index].y;

		bottom_left[index].x = bottom_left[index].x;
		bottom_left[index].y = bottom_left[index].y;*/

		angle -= step;

		++index;

		++i;
	}

	static GLubyte clr[] = { 156, 207, 255, 128 }; // Light blue, 50% transparent.

	if (color)
		glColor4fv(color);
	else
		glColor4ubv(clr);

	glBegin( GL_TRIANGLE_STRIP);
	{
		// Top
		for (i = segment_count - 1; i >= 0; i--) {
			glVertex2f(top_left[i].x, top_left[i].y);
			glVertex2f(top_right[i].x, top_right[i].y);
		}

		// In order to stop and restart the strip.
		glVertex2f(top_right[0].x, top_right[0].y);
		glVertex2f(top_right[0].x, top_right[0].y);

		// Center
		glVertex2f(top_right[0].x, top_right[0].y);
		glVertex2f(top_left[0].x, top_left[0].y);
		glVertex2f(bottom_right[0].x, bottom_right[0].y);
		glVertex2f(bottom_left[0].x, bottom_left[0].y);

		// Bottom
		for (i = 0; i != segment_count; i++) {
			glVertex2f(bottom_right[i].x, bottom_right[i].y);
			glVertex2f(bottom_left[i].x, bottom_left[i].y);
		}
	}
	glEnd();
} //DrawRoundRect

//#endif
/*typedef struct
 {
 float x;
 float y;

 } Vector2f;
 */

void RoundRect(int x, int y, int width, int height, int radius,
		int resolution) {
	float step = (2.0f * M_PI) / resolution, angle = 0.0f, x_offset, y_offset;

	int i = 0;

	unsigned int index = 0, segment_count = (int) (resolution / 4);

	Vector2f *top_left = (Vector2f *) malloc(segment_count * sizeof(Vector2f)),
			*bottom_left = (Vector2f *) malloc(
					segment_count * sizeof(Vector2f)), *top_right =
					(Vector2f *) malloc(segment_count * sizeof(Vector2f)),
			*bottom_right = (Vector2f *) malloc(
					segment_count * sizeof(Vector2f)), bottom_left_corner = { x
					+ radius, y - height + radius };

	while (i != segment_count) {
		x_offset = cosf(angle);
		y_offset = sinf(angle);

		top_left[index].x = bottom_left_corner.x - (x_offset * radius);
		top_left[index].y = (height - (radius * 2.0f)) + bottom_left_corner.y
				- (y_offset * radius);

		top_right[index].x = (width - (radius * 2.0f)) + bottom_left_corner.x
				+ (x_offset * radius);
		top_right[index].y = (height - (radius * 2.0f)) + bottom_left_corner.y
				- (y_offset * radius);

		bottom_right[index].x = (width - (radius * 2.0f)) + bottom_left_corner.x
				+ (x_offset * radius);
		bottom_right[index].y = bottom_left_corner.y + (y_offset * radius);

		bottom_left[index].x = bottom_left_corner.x - (x_offset * radius);
		bottom_left[index].y = bottom_left_corner.y + (y_offset * radius);

		top_left[index].x = roundf(top_left[index].x);
		top_left[index].y = roundf(top_left[index].y);

		top_right[index].x = roundf(top_right[index].x);
		top_right[index].y = roundf(top_right[index].y);

		bottom_right[index].x = roundf(bottom_right[index].x);
		bottom_right[index].y = roundf(bottom_right[index].y);

		bottom_left[index].x = roundf(bottom_left[index].x);
		bottom_left[index].y = roundf(bottom_left[index].y);

		angle -= step;

		++index;

		++i;
	}

	glBegin( GL_TRIANGLE_STRIP);
	{
		// Top
		{
			i = 0;
			while (i != segment_count) {
				//glColor4f( 1.0f, 0.0f, 0.0f, 1.0f );
				glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
				glVertex2i(top_left[i].x, top_left[i].y);

				//glColor4f( 0.0f, 1.0f, 0.0f, 1.0f );
				glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
				glVertex2i(top_right[i].x, top_right[i].y);

				++i;
			}
		}

		// In order to stop and restart the strip.
		glColor4f(0.0f, 1.0f, 0.0f, 1.5f);
		glVertex2i(top_right[0].x, top_right[0].y);

		glColor4f(0.0f, 1.0f, 0.0f, 1.5f);
		glVertex2i(top_right[0].x, top_right[0].y);

		// Center
		{
			//glColor4f( 0.0f, 1.0f, 0.0f,  1.0f );
			glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
			glVertex2i(top_right[0].x, top_right[0].y);

			//glColor4f( 1.0f, 0.0f, 0.0f,  1.0f );
			glColor4f(0.0f, 0.0f, 0.0f, 1.0f);
			glVertex2i(top_left[0].x, top_left[0].y);

			//glColor4f( 0.0f, 0.0f, 1.0f,  1.0f );
			glColor4f(0.5f, 0.5f, 0.5f, 1.0f);
			glVertex2i(bottom_right[0].x, bottom_right[0].y);

			//glColor4f( 1.0f, 1.0f, 0.0f,  1.0f );
			glColor4f(0.5f, 0.5f, 0.5f, 1.0f);
			glVertex2i(bottom_left[0].x, bottom_left[0].y);
		}

		// Bottom
		i = 0;
		while (i != segment_count) {
			//glColor4f( 0.0f, 0.0f, 1.0f,  1.0f );
			glColor4f(0.5f, 0.5f, 0.5f, 1.0f);
			glVertex2i(bottom_right[i].x, bottom_right[i].y);

			//glColor4f( 1.0f, 1.0f, 0.0f,  1.0f );
			glColor4f(0.5f, 0.5f, 0.5f, 1.0f);
			glVertex2i(bottom_left[i].x, bottom_left[i].y);

			++i;
		}
	}
	glEnd();

	glBegin( GL_LINE_STRIP);

//glColor4f( 0.0f, 1.0f, 1.0f, 1.0f );
	glColor4f(1.0f, 0.5f, 0.0f, 1.0f);

// Border
	{
		i = (segment_count - 1);
		while (i > -1) {
			glVertex2i(top_left[i].x, top_left[i].y);

			--i;
		}

		i = 0;
		while (i != segment_count) {
			glVertex2i(bottom_left[i].x, bottom_left[i].y);

			++i;
		}

		i = (segment_count - 1);
		while (i > -1) {
			glVertex2i(bottom_right[i].x, bottom_right[i].y);

			--i;
		}

		i = 0;
		while (i != segment_count) {
			glVertex2i(top_right[i].x, top_right[i].y);

			++i;
		}

		// Close the border.
		glVertex2i(top_left[(segment_count - 1)].x,
				top_left[(segment_count - 1)].y);
	}
	glEnd();

	glBegin( GL_LINES);

//glColor4f( 0.0f, 1.0f, 1.0f, 1.0f );
	glColor4f(0.0f, 0.5f, 1.0f, 1.0f);

// Separator
	{
		// Top bar
		glVertex2i(top_right[0].x, top_right[0].y);

		glVertex2i(top_left[0].x, top_left[0].y);

		// Bottom bar
		glVertex2i(bottom_left[0].x, bottom_left[0].y);

		glVertex2i(bottom_right[0].x, bottom_right[0].y);
	}
	glEnd();

	free(top_left);
	free(bottom_left);
	free(top_right);
	free(bottom_right);
}