WidgetVerticalScrollbar.java

package pneumaticCraft.client.gui.widget;

import net.minecraft.client.Minecraft;
import net.minecraft.client.gui.Gui;
import net.minecraft.util.MathHelper;
import net.minecraft.util.ResourceLocation;

import org.lwjgl.input.Mouse;
import org.lwjgl.opengl.GL11;

import pneumaticCraft.lib.Textures;

public class WidgetVerticalScrollbar extends WidgetBase{
    public float currentScroll;
    private int states;
    private boolean listening;
    private boolean dragging;
    private boolean wasClicking;
    private boolean enabled = true;
    private static ResourceLocation scrollTexture = new ResourceLocation(Textures.GUI_LOCATION + "widget/verticalScrollbar.png");

    public WidgetVerticalScrollbar(int x, int y, int height){
        this(-1, x, y, height);
    }

    public WidgetVerticalScrollbar(int id, int x, int y, int height){
        super(id, x, y, 14, height);
    }

    public WidgetVerticalScrollbar setStates(int states){
        this.states = states;
        return this;
    }

    public WidgetVerticalScrollbar setCurrentState(int state){
        if(state >= states) throw new IllegalArgumentException("State to high! max = " + states + ", tried to assign " + state);
        currentScroll = (float)state / states;
        return this;
    }

    @Override
    public void handleMouseInput(){
        if(listening) {
            int wheel = -Mouse.getDWheel();
            wheel = MathHelper.clamp_int(wheel, -1, 1);
            currentScroll += (float)wheel / states;
        }
    }

    public WidgetVerticalScrollbar setListening(boolean listening){
        this.listening = listening;
        return this;
    }

    public int getState(){
        float scroll = currentScroll;
        scroll += 0.5F / states;
        return MathHelper.clamp_int((int)(scroll * states), 0, states);
    }

    public WidgetVerticalScrollbar setEnabled(boolean enabled){
        this.enabled = enabled;
        wasClicking = true;
        return this;
    }

    @Override
    public void render(int mouseX, int mouseY, float partialTick){
        GL11.glColor4d(1, 1, 1, 1);
        if(!Mouse.isButtonDown(0)) dragging = false;
        if(!wasClicking && Mouse.isButtonDown(0) && getBounds().contains(mouseX, mouseY)) {
            dragging = true;
        }
        if(!enabled) dragging = false;
        wasClicking = Mouse.isButtonDown(0);
        if(dragging) currentScroll = (float)(mouseY - 7 - getBounds().y) / (getBounds().height - 17);
        currentScroll = MathHelper.clamp_float(currentScroll, 0, 1);
        Minecraft.getMinecraft().getTextureManager().bindTexture(scrollTexture);
        Gui.func_146110_a(x, y, 12, 0, getBounds().width, 1, 26, 15);
        for(int i = 0; i < getBounds().height - 2; i++)
            Gui.func_146110_a(x, y + 1 + i, 12, 1, getBounds().width, 1, 26, 15);
        Gui.func_146110_a(x, y + getBounds().height - 1, 12, 14, getBounds().width, 1, 26, 15);

        if(!enabled) GL11.glColor4d(0.6, 0.6, 0.6, 1);
        Gui.func_146110_a(x + 1, y + 1 + (int)((getBounds().height - 17) * currentScroll), 0, 0, 12, 15, 26, 15);
        GL11.glColor4d(1, 1, 1, 1);
    }

}