snuvi-engine/src/me/hammerle/snuviengine/api/FixedWindowView.java

package me.hammerle.snuviengine.api;

public class FixedWindowView implements WindowView {
    private final int width;
    private final int height;
    private final int fontScale;

    public FixedWindowView(int width, int height, int fontScale) {
        this.width = width;
        this.height = height;
        this.fontScale = fontScale;
    }

    @Override
    public int getScale(int width, int height) {
        return Math.max(width / this.width, 1);
    }

    @Override
    public int getFontScale(int width, int height) {
        return fontScale;
    }

    @Override
    public int getWidth(int newWidth, int newHeight) {
        return Math.max(getMaxScale(newWidth, newHeight) * width, width);
    }

    @Override
    public int getHeight(int newWidth, int newHeight) {
        return Math.max(getMaxScale(newWidth, newHeight) * height, height);
    }

    private int getMaxScale(int newWidth, int newHeight) {
        return Math.max(getNearestScale(newWidth, width), getNearestScale(newHeight, height));
    }

    private int getNearestScale(int value, int multiple) {
        float scale = (float) value / multiple;
        int roundedScale = (int) scale;
        if(scale == roundedScale) {
            return roundedScale;
        }
        float diff = scale - roundedScale;
        roundedScale += diff < 0.5f ? 1 : 0;
        return roundedScale;
    }
}