How to generate electricity

Electricity.cpp

/*
Electricity:
resolution_ = 0; means straight line
pointA_, pointB_; are vec4s
*/

void ElectricCurrent::createVertexData(){
	int tfloats = (2+resolution_) * 4; //num_points * num_floats_per_point
	GLfloat data[tfloats];
	int atIndx = 0;
	atIndx = copyData(pointA_, data, atIndx);
	for(int p = 0; p < resolution_; p++){
		GLfloat point = 1.0/GLfloat(resolution_+1)*(p+1.0);
		glm::vec4 pt = glm::mix(pointA_, pointB_, glm::vec4(point+GLfloat(rand())/GLfloat(RAND_MAX)*0.1,point+GLfloat(rand())/GLfloat(RAND_MAX)*0.1, 0.0, 1.0));
		atIndx = copyData(pt, data, atIndx);
	}
	atIndx = copyData(pointB_, data, atIndx);

	glBindBuffer(GL_ARRAY_BUFFER, buffer_);
	glBufferData(GL_ARRAY_BUFFER, sizeof(GLfloat) * tfloats, data, GL_DYNAMIC_DRAW);
}

int ElectricCurrent::copyData(glm::vec4 pt, GLfloat *data, int atIndex){	
	data[atIndex++] = pt.x;
	data[atIndex++] = pt.y;
	data[atIndex++] = pt.z;
	data[atIndex++] = pt.w;
	return atIndex;
}