GUI Library/Layer

public class Layer {
    final String ID;
    int lastEvent; // Last event triggered by an element within this layer

    Square geomVisible;
    Square geomActual;

    double hMin, hMax, hLength, vMin, vMax, vLength;

    Element[] elements;


    public Layer(String ID, Element[] elements, Square geomVisible, Square geomActual){
        this.ID = ID;
        this.elements = elements;
        this.geomActual = geomActual;
        this.geomVisible = geomVisible;



        hMin = (geomVisible.x1-geomActual.x1) / (geomActual.x2-geomActual.x1);
        hMax = (geomVisible.x2-geomActual.x1) / (geomActual.x2-geomActual.x1);
        vMin = (geomVisible.y1-geomActual.y1) / (geomActual.y2-geomActual.y1);
        vMax = (geomVisible.y2-geomActual.y1) / (geomActual.y2-geomActual.y1);

        if(hMin < 0)
            hMin = 0;
        if(hMax > 1)
            hMax = 1;
        if(vMin < 0)
            vMin = 0;
        if(vMax > 1)
            vMax = 1;

        hLength = hMax-hMin;
        vLength = vMax-vMin;
    }

    // Works out which element has been clicked. A return of elements.length mean no elements were clicked.
    public int computeClickedElement(int mouseX, int mouseY){
        int clickedElement = elements.length;

        for(int i=0; i<elements.length; i++){
            if(elements[i].geom.x1+geomActual.x1 < mouseX){
                if(elements[i].geom.x2+geomActual.x1 > mouseX){
                    if(elements[i].geom.y1+geomActual.y1 < mouseY){
                        if(elements[i].geom.y2+geomActual.y1 > mouseY){
                            clickedElement = i;
                            i = elements.length;
                        }
                    }
                }
            }
            if(geomVisible.x1+((geomVisible.x2-geomVisible.x1)*hMin) < mouseX){
                if(geomVisible.x1+((geomVisible.x2-geomVisible.x1)*hMax) > mouseX){
                    if(geomVisible.y1 <= mouseY){
                        if(geomVisible.y1+10 >= mouseY){
                            clickedElement = elements.length+1;
                            i = elements.length;
                        }
                    }
                }
            }
            if(geomVisible.y1+((geomVisible.y2-geomVisible.y1)*vMin) < mouseY){
                if(geomVisible.y1+((geomVisible.y2-geomVisible.y1)*vMax) > mouseY){
                    if(geomVisible.x2-10 <= mouseX){
                        if(geomVisible.x2 >= mouseX){
                            clickedElement = elements.length+2;
                            i = elements.length;
                        }
                    }
                }
            }
            if(geomVisible.x2-10 < mouseX){
                if(geomVisible.x2 > mouseX){
                    if(geomVisible.y2-10 < mouseY){
                        if(geomVisible.y2 > mouseY){
                            clickedElement = elements.length+3;
                            i = elements.length;
                        }
                    }
                }
            }
        }

        return clickedElement;
    }

    public void resize(int deltaX, int deltaY){
        geomVisible.x2 += deltaX;
        geomVisible.y2 += deltaY;

        hMin = (geomVisible.x1-geomActual.x1) / (geomActual.x2-geomActual.x1);
        hMax = (geomVisible.x2-geomActual.x1) / (geomActual.x2-geomActual.x1);
        vMin = (geomVisible.y1-geomActual.y1) / (geomActual.y2-geomActual.y1);
        vMax = (geomVisible.y2-geomActual.y1) / (geomActual.y2-geomActual.y1);
        hLength = hMax-hMin;
        vLength = vMax-vMin;

        update();
        System.out.println(geomActual.y2-geomActual.y1);
    }

    public void scroll(int deltaX, int deltaY, int direction){
        double p1 = geomVisible.x1+((geomVisible.x2-geomVisible.x1)*hMin);
        double p2 = geomVisible.x1+((geomVisible.x2-geomVisible.x1)*hMax);
        double q1 = geomVisible.y1+((geomVisible.y2-geomVisible.y1)*vMin);
        double q2 = geomVisible.y1+((geomVisible.y2-geomVisible.y1)*vMax);

        switch(direction){
        case 1:
            hMin = (p1+deltaX-geomVisible.x1)/(geomVisible.x2-geomVisible.x1);
            hMax = (p2+deltaX-geomVisible.x1)/(geomVisible.x2-geomVisible.x1);
            if(hMin < 0){
                hMax += 0-hMin;
                hMin = 0;
            }
            if(hMax > 1){
                hMin += 1-hMax;
                hMax = 1;
            }
            break;
        case 2:
            vMin = (q1+deltaY-geomVisible.y1)/(geomVisible.y2-geomVisible.y1);
            vMax = (q2+deltaY-geomVisible.y1)/(geomVisible.y2-geomVisible.y1);
            if(vMin < 0){
                vMax += 0-vMin;
                vMin = 0;
            }
            if(vMax > 1){
                vMin += 1-vMax;
                vMax = 1;
            }
            break;
        }

        update();
    }

    public void translate(int deltaX, int deltaY){
        geomActual.x1 += deltaX;
        geomActual.x2 += deltaX;
        geomActual.y1 += deltaY;
        geomActual.y2 += deltaY;

        geomVisible.x1 += deltaX;
        geomVisible.x2 += deltaX;
        geomVisible.y1 += deltaY;
        geomVisible.y2 += deltaY;
    }

    public void update(){
        if(hMax > 1){
            hMax = 1;
            hMin = 1-hLength;
            if(hMin < 0){
                hMin = 0;
                hLength = 1;
            }
        }
        if(vMax > 1){
            vMax = 1;
            vMin = 1-vLength;
            if(vMin < 0){
                vMin = 0;
                vLength = 1;
            }
        }


        double tempX1 = geomActual.x1;
        double tempX2 = geomActual.x2;
        double tempY1 = geomActual.y1;
        double tempY2 = geomActual.y2;

        geomActual.x1 = geomVisible.x1-(hMin*(tempX2-tempX1));
        geomActual.x2 = geomActual.x1+tempX2-tempX1;
        geomActual.y1 = geomVisible.y1-(vMin*(tempY2-tempY1));
        geomActual.y2 = geomActual.y1+tempY2-tempY1;
    }
}