Question

我正在研究基于磁贴的挖掘机游戏，我希望在玩家周围使用逐渐照明，想想Terraria。我目前只是将图像与矩形重叠，其中该矩形上的alpha是我希望拥有的亮度（0.01 =黑色，1 =明亮），这可以正常工作。这不是我如何设置我需要帮助的照明，它是如何编写一个紧凑而有效的算法，在块越靠近播放器时让我获得更大的数字，并且更小的数字街区远离玩家。数字应在（1 - 0.01）范围内。每次玩家移动时我都会调用以下方法：

public void calculateBlockBrightness(int playerInRow, int playerInCol) {

    int affectedBlocks = 5;
    float brightness;

    // Loops through all blocks within (affectedBlocks) blocks of the player
    for (int row = playerInRow - affectedBlocks; row <= playerInRow + affectedBlocks; row++) {
        for (int col = playerInCol - affectedBlocks; col <= playerInCol + affectedBlocks; col++) {

            // Not all blocks should be affected by this method
            if (blockNotRelevantForBrightness(row, col))
                continue;

            // If the block is within (affectedBlocks - 1) blocks of the player
            if (row >= playerInRow - (affectedBlocks - 1) && row <= playerInRow + (affectedBlocks - 1)
                    && col >= playerInCol - (affectedBlocks - 1) && col <= playerInCol + (affectedBlocks - 1)) {

                /*
                 * Algorithm
                 */

                blocks[row][col].setBrightnessPercentage(brightness);

            // Reset the "outer layer" blocks to default brightness.
            } else {
                blocks[row][col].setBrightnessPercentage(blocks[row][col].getBrightnessDefault());

            }
        }
    }
}

Answer 1

在这种情况下，通过两个步骤计算所需的值通常是有益的：

计算[0 ... 1]
根据插值

此处的插值是＆＃34;相对＆＃34; 距离，用于在最小和最大亮度之间进行插值。

两个图块之间的距离可以计算为

sqrt(rowDifference² + columnDifference²)

（顺便说一句，这可以方便地使用Math#hypot计算。）

受影响的磁贴在水平和垂直方向上对播放器磁贴的最大距离为(affectedBlocks - 1)。对于一对图块，即图块(row, col)和(playerInRow, playerInCol)，现在可以计算这些图块之间的距离，并将其除以最大距离，以获得相对距离作为[0]中的值，1]。该值可用于计算适当的亮度。

private float computeBrightness(
    int row, int col, int playerRow, int playerCol, int affectedBlocks)
{
    // Compute the distance of the tile (row, col) to the player tile
    double distance = Math.hypot(row - playerRow, col - playerCol);

    // Compute the maximum possible distance of a tile
    double maxDistance = Math.hypot(affectedBlocks - 1, affectedBlocks -1);

    // Compute the relative distance, as a value in [0,1]
    double relative = distance / maxDistance;

    // Compute the brightness for the relative distance
    double minBrightness = 0.01;
    double maxBrightness = 1.0;
    double brightness = 
        maxBrightness - relative * (maxBrightness - minBrightness);

    System.out.println(
        "For " + row + " " + col + " brightness is " + brightness);

    return (float)brightness;
}

附注：假设affectedBlocks是常数，最大距离也是常数，并且可以存储为常数值字段，例如：

private static final int AFFECTED_BLOCKS = 5;
private static final double MAX_DISTANCE = 
    Math.hypot(AFFECTED_BLOCKS - 1, AFFECTED_BLOCKS - 1);

在基于平铺的游戏中围绕玩家照明

1 个答案: