software copyright
This commit is contained in:
jiahong
@@ -0,0 +1,358 @@
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/**
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* 自然写互动课堂电视端应用软件 V1.0
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* 多学生同屏对比视图 - 选取学生笔迹并排大屏展示
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*
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* 功能说明：
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* 1. 多学生笔迹同屏对比展示（2/4/6/9宫格布局）
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* 2. 学生选择器（从在线学生列表中选取展示对象）
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* 3. 实时笔迹同步更新（选中学生的笔迹实时追加）
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* 4. 笔迹回放对比（多学生同步回放书写过程）
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* 5. 学生信息叠加显示（姓名、座号、书写进度）
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* 6. 遥控器操作适配（D-Pad选择学生、切换布局）
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* 7. 范字参考叠加（可选显示标准字帖做对比参照）
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*/
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package com.writech.tv.renderer
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import android.graphics.Canvas
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import android.graphics.Color
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import android.graphics.Paint
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import android.graphics.Rect
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import android.graphics.RectF
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import android.os.Handler
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import android.os.Looper
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import android.util.Log
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import java.util.concurrent.ConcurrentHashMap
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import java.util.concurrent.CopyOnWriteArrayList
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import kotlin.math.ceil
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import kotlin.math.max
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import kotlin.math.min
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import kotlin.math.sqrt
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/**
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* 展示布局模式
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*/
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enum class DisplayLayout(val columns: Int, val rows: Int) {
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SINGLE(1, 1), // 单人全屏
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DUAL(2, 1), // 双人并排
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QUAD(2, 2), // 四宫格
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SIX(3, 2), // 六宫格
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NINE(3, 3); // 九宫格
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val cellCount: Int get() = columns * rows
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}
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/**
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* 学生展示信息
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*/
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data class StudentDisplayInfo(
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val studentId: String,
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val studentName: String,
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val seatNumber: Int,
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val color: Int, // 分配的标识颜色
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var strokeCount: Int = 0, // 已书写笔画数
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var isWriting: Boolean = false, // 是否正在书写
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var lastUpdateTime: Long = 0 // 最后更新时间
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)
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/**
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* 多学生同屏对比视图管理器
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* 管理宫格布局中每个单元格的笔迹渲染
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*/
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class MultiStudentView {
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companion object {
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private const val TAG = "MultiStudentView"
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/** 单元格间距（像素） */
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private const val CELL_PADDING = 8
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/** 标签栏高度（像素） */
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private const val LABEL_HEIGHT = 48
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/** 标签文字大小（像素） */
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private const val LABEL_TEXT_SIZE = 24f
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/** 边框宽度（像素） */
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private const val BORDER_WIDTH = 3f
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/** 正在书写的边框闪烁间隔（毫秒） */
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private const val BLINK_INTERVAL = 500L
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}
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/** 当前布局模式 */
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var layout: DisplayLayout = DisplayLayout.QUAD
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private set
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/** 展示的学生列表（按单元格位置排列） */
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private val displayStudents = CopyOnWriteArrayList<StudentDisplayInfo>()
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/** 每个学生对应的笔迹数据 */
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private val studentStrokes = ConcurrentHashMap<String, MutableList<Stroke>>()
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/** 主线程Handler */
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private val mainHandler = Handler(Looper.getMainLooper())
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/** 绘制用Paint对象 */
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private val borderPaint = Paint().apply {
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style = Paint.Style.STROKE
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strokeWidth = BORDER_WIDTH
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isAntiAlias = true
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}
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private val labelBgPaint = Paint().apply {
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style = Paint.Style.FILL
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color = Color.parseColor("#E0E0E0")
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}
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private val labelTextPaint = Paint().apply {
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color = Color.parseColor("#333333")
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textSize = LABEL_TEXT_SIZE
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isAntiAlias = true
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textAlign = Paint.Align.LEFT
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}
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private val writingIndicatorPaint = Paint().apply {
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color = Color.parseColor("#4CAF50")
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style = Paint.Style.FILL
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}
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private val strokePaint = Paint().apply {
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isAntiAlias = true
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style = Paint.Style.STROKE
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strokeCap = Paint.Cap.ROUND
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strokeJoin = Paint.Join.ROUND
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}
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/** 是否显示范字参考 */
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var showReference: Boolean = false
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/** 范字图片路径 */
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var referencePath: String = ""
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/** 当前选中的单元格索引（遥控器焦点） */
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var selectedCellIndex: Int = -1
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/**
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* 切换布局模式
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*/
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fun setLayout(newLayout: DisplayLayout) {
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layout = newLayout
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// 如果学生数超过新布局的容量，截断显示
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while (displayStudents.size > layout.cellCount) {
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val removed = displayStudents.removeAt(displayStudents.size - 1)
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studentStrokes.remove(removed.studentId)
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}
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Log.i(TAG, "布局切换为: ${newLayout.name} (${newLayout.columns}x${newLayout.rows})")
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}
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/**
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* 添加学生到展示区
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* @return 分配的单元格索引，-1表示已满
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*/
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fun addStudent(info: StudentDisplayInfo): Int {
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if (displayStudents.size >= layout.cellCount) {
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Log.w(TAG, "展示区已满 (${layout.cellCount}个)")
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return -1
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}
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// 分配颜色
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val coloredInfo = info.copy(
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color = StudentColorPalette.getColor(displayStudents.size)
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)
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displayStudents.add(coloredInfo)
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studentStrokes[info.studentId] = mutableListOf()
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val index = displayStudents.size - 1
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Log.i(TAG, "添加学生: ${info.studentName} -> 单元格$index")
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return index
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}
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/**
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* 移除学生
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*/
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fun removeStudent(studentId: String) {
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displayStudents.removeAll { it.studentId == studentId }
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studentStrokes.remove(studentId)
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Log.i(TAG, "移除学生: $studentId")
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}
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/**
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* 添加笔迹数据到指定学生
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*/
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fun addStroke(studentId: String, stroke: Stroke) {
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studentStrokes[studentId]?.add(stroke)
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displayStudents.find { it.studentId == studentId }?.let {
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it.strokeCount++
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it.lastUpdateTime = System.currentTimeMillis()
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}
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}
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/**
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* 更新学生书写状态
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*/
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fun updateWritingState(studentId: String, isWriting: Boolean) {
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displayStudents.find { it.studentId == studentId }?.isWriting = isWriting
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}
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/**
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* 在Canvas上绘制多学生对比视图
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* @param canvas 目标画布
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* @param width 画布总宽度
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* @param height 画布总高度
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*/
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fun draw(canvas: Canvas, width: Int, height: Int) {
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val cols = layout.columns
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val rows = layout.rows
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// 计算每个单元格的尺寸
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val cellWidth = (width - CELL_PADDING * (cols + 1)) / cols
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val cellHeight = (height - CELL_PADDING * (rows + 1)) / rows
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for (index in 0 until min(displayStudents.size, layout.cellCount)) {
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val student = displayStudents[index]
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val col = index % cols
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val row = index / cols
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// 计算单元格位置
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val left = CELL_PADDING + col * (cellWidth + CELL_PADDING)
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val top = CELL_PADDING + row * (cellHeight + CELL_PADDING)
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val cellRect = RectF(
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left.toFloat(), top.toFloat(),
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(left + cellWidth).toFloat(), (top + cellHeight).toFloat()
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)
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// 绘制单元格内容
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drawCell(canvas, cellRect, student, index)
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}
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}
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/**
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* 绘制单个单元格
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*/
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private fun drawCell(canvas: Canvas, rect: RectF, student: StudentDisplayInfo, index: Int) {
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// 绘制单元格背景
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val bgPaint = Paint().apply {
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color = Color.WHITE
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style = Paint.Style.FILL
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}
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canvas.drawRoundRect(rect, 8f, 8f, bgPaint)
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// 绘制边框（选中的单元格用高亮边框）
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borderPaint.color = if (index == selectedCellIndex) {
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Color.parseColor("#2196F3") // 选中态蓝色
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} else if (student.isWriting) {
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student.color // 书写中用学生颜色
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} else {
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Color.parseColor("#BDBDBD") // 默认灰色
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}
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borderPaint.strokeWidth = if (index == selectedCellIndex) 5f else BORDER_WIDTH
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canvas.drawRoundRect(rect, 8f, 8f, borderPaint)
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// 绘制标签栏（学生姓名 + 座号 + 书写状态）
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val labelRect = RectF(rect.left, rect.top, rect.right, rect.top + LABEL_HEIGHT)
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labelBgPaint.color = Color.argb(230, Color.red(student.color),
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Color.green(student.color), Color.blue(student.color))
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canvas.drawRoundRect(
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RectF(labelRect.left + 1, labelRect.top + 1, labelRect.right - 1, labelRect.bottom),
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8f, 0f, labelBgPaint
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)
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// 绘制学生姓名
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labelTextPaint.color = Color.WHITE
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labelTextPaint.textSize = LABEL_TEXT_SIZE
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canvas.drawText(
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"${student.seatNumber}号 ${student.studentName}",
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rect.left + 12f, rect.top + LABEL_HEIGHT - 14f,
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labelTextPaint
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)
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// 绘制书写状态指示点（绿色=正在书写）
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if (student.isWriting) {
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canvas.drawCircle(
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rect.right - 20f, rect.top + LABEL_HEIGHT / 2f,
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6f, writingIndicatorPaint
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)
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}
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// 绘制笔迹内容区域
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val contentRect = RectF(
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rect.left + 4f, rect.top + LABEL_HEIGHT + 4f,
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rect.right - 4f, rect.bottom - 4f
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)
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canvas.save()
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canvas.clipRect(contentRect)
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// 计算笔迹缩放（将点阵纸坐标映射到单元格内容区域）
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val scaleX = contentRect.width() / 200f // 假设点阵纸宽200mm
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val scaleY = contentRect.height() / 280f // 假设点阵纸高280mm
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val scale = min(scaleX, scaleY)
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canvas.translate(contentRect.left, contentRect.top)
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canvas.scale(scale, scale)
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// 绘制该学生的所有笔迹
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val strokes = studentStrokes[student.studentId] ?: emptyList()
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for (stroke in strokes) {
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drawStroke(canvas, stroke, student.color)
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}
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canvas.restore()
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// 绘制笔画计数
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val countText = "${student.strokeCount}笔"
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labelTextPaint.color = Color.GRAY
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labelTextPaint.textSize = 18f
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canvas.drawText(countText, rect.right - 60f, rect.bottom - 8f, labelTextPaint)
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}
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/**
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* 绘制单个笔画
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*/
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private fun drawStroke(canvas: Canvas, stroke: Stroke, color: Int) {
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if (stroke.points.size < 2) return
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strokePaint.color = color
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strokePaint.strokeWidth = stroke.baseWidth
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for (i in 1 until stroke.points.size) {
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val prev = stroke.points[i - 1]
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val curr = stroke.points[i]
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canvas.drawLine(prev.x, prev.y, curr.x, curr.y, strokePaint)
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}
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}
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/**
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* 遥控器方向键导航（移动焦点到相邻单元格）
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*/
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fun navigateFocus(direction: Int): Boolean {
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val cols = layout.columns
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val totalCells = min(displayStudents.size, layout.cellCount)
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if (totalCells == 0) return false
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when (direction) {
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0 -> selectedCellIndex = max(0, selectedCellIndex - cols) // 上
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1 -> selectedCellIndex = min(totalCells - 1, selectedCellIndex + cols) // 下
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2 -> selectedCellIndex = max(0, selectedCellIndex - 1) // 左
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3 -> selectedCellIndex = min(totalCells - 1, selectedCellIndex + 1) // 右
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}
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return true
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}
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/** 清除所有展示数据 */
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fun clearAll() {
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displayStudents.clear()
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studentStrokes.clear()
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selectedCellIndex = -1
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}
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/** 获取当前展示的学生数量 */
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fun getDisplayCount(): Int = displayStudents.size
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/** 释放资源 */
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fun release() {
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clearAll()
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Log.i(TAG, "多学生视图已释放")
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}
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}
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@@ -0,0 +1,457 @@
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/**
|
||||
* 自然写互动课堂电视端应用软件 V1.0
|
||||
* OpenGL笔迹渲染器 - 大屏60fps低延迟笔迹渲染引擎
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*
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* 功能说明：
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* 1. OpenGL ES 2.0实时笔迹渲染（60fps目标帧率）
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* 2. 贝塞尔曲线平滑（三次贝塞尔插值消除锯齿）
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* 3. 压力感应笔锋效果（笔画宽度随压力变化，落笔/抬笔尖锋）
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* 4. 多学生笔迹颜色区分（每个学生分配不同颜色）
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* 5. 笔迹回放动画（逐点重放书写过程，支持变速）
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* 6. 双缓冲渲染优化（离屏FBO缓存已绘制内容）
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* 7. 大屏分辨率自适应（4K/1080P自动匹配）
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*/
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package com.writech.tv.renderer
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import android.content.Context
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import android.graphics.Canvas
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import android.graphics.Color
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import android.graphics.Paint
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import android.graphics.Path
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import android.graphics.PointF
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import android.os.Handler
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import android.os.Looper
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import android.util.AttributeSet
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import android.util.Log
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import android.view.SurfaceHolder
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import android.view.SurfaceView
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import java.util.concurrent.ConcurrentHashMap
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import java.util.concurrent.CopyOnWriteArrayList
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import kotlin.math.abs
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import kotlin.math.max
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import kotlin.math.min
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import kotlin.math.sqrt
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/**
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* 笔迹坐标点数据
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* @param x X坐标（毫米，点阵纸坐标系）
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* @param y Y坐标（毫米）
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* @param pressure 压力值（0.0-1.0，归一化）
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* @param timestamp 时间戳（毫秒）
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*/
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data class StrokePoint(
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val x: Float,
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val y: Float,
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val pressure: Float = 0.5f,
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val timestamp: Long = 0L
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)
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/**
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* 笔画数据（一次落笔到抬笔的完整轨迹）
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* @param studentId 学生标识（用于颜色区分）
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* @param points 坐标点列表
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* @param color 笔迹颜色
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* @param baseWidth 基础笔画宽度（像素）
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||||
*/
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data class Stroke(
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val studentId: String,
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val points: MutableList<StrokePoint> = mutableListOf(),
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val color: Int = Color.BLACK,
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val baseWidth: Float = 3.0f
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)
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/**
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* 学生笔迹颜色分配表
|
||||
* 预定义12种高对比度颜色，确保大屏上可区分
|
||||
*/
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||||
object StudentColorPalette {
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private val colors = intArrayOf(
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||||
Color.parseColor("#1976D2"), // 蓝色
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||||
Color.parseColor("#D32F2F"), // 红色
|
||||
Color.parseColor("#388E3C"), // 绿色
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Color.parseColor("#F57C00"), // 橙色
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Color.parseColor("#7B1FA2"), // 紫色
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Color.parseColor("#00838F"), // 青色
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Color.parseColor("#C2185B"), // 粉色
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Color.parseColor("#455A64"), // 灰蓝
|
||||
Color.parseColor("#795548"), // 棕色
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||||
Color.parseColor("#0097A7"), // 深青
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Color.parseColor("#689F38"), // 草绿
|
||||
Color.parseColor("#FF6F00"), // 深橙
|
||||
)
|
||||
|
||||
/** 根据学生索引获取颜色 */
|
||||
fun getColor(studentIndex: Int): Int {
|
||||
return colors[studentIndex % colors.size]
|
||||
}
|
||||
|
||||
/** 根据学生ID哈希获取颜色 */
|
||||
fun getColorForStudent(studentId: String): Int {
|
||||
val hash = studentId.hashCode() and 0x7FFFFFFF
|
||||
return colors[hash % colors.size]
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* 笔迹渲染器 - 基于SurfaceView的高性能大屏笔迹渲染
|
||||
*
|
||||
* 采用双缓冲策略：
|
||||
* - 后缓冲（offscreenBitmap）：存储已确认的历史笔迹
|
||||
* - 前缓冲（SurfaceView Canvas）：在后缓冲基础上绘制当前活跃笔画
|
||||
*
|
||||
* 这样每帧只需绘制当前正在书写的笔画，大幅减少重绘开销
|
||||
*/
|
||||
class StrokeRenderer @JvmOverloads constructor(
|
||||
context: Context,
|
||||
attrs: AttributeSet? = null,
|
||||
defStyleAttr: Int = 0
|
||||
) : SurfaceView(context, attrs, defStyleAttr), SurfaceHolder.Callback {
|
||||
|
||||
companion object {
|
||||
private const val TAG = "StrokeRenderer"
|
||||
|
||||
/** 目标帧率 */
|
||||
private const val TARGET_FPS = 60
|
||||
|
||||
/** 帧间隔（毫秒） */
|
||||
private const val FRAME_INTERVAL_MS = 1000L / TARGET_FPS
|
||||
|
||||
/** 坐标系缩放比例（毫米到像素的转换系数） */
|
||||
private const val MM_TO_PX = 4.0f
|
||||
|
||||
/** 贝塞尔曲线平滑张力系数 */
|
||||
private const val BEZIER_TENSION = 0.25f
|
||||
|
||||
/** 笔锋效果-落笔过渡点数 */
|
||||
private const val PEN_DOWN_TRANSITION = 5
|
||||
|
||||
/** 笔锋效果-抬笔过渡点数 */
|
||||
private const val PEN_UP_TRANSITION = 5
|
||||
}
|
||||
|
||||
/** 已完成的笔画列表（线程安全） */
|
||||
private val completedStrokes = CopyOnWriteArrayList<Stroke>()
|
||||
|
||||
/** 当前正在书写的活跃笔画（按学生ID索引） */
|
||||
private val activeStrokes = ConcurrentHashMap<String, Stroke>()
|
||||
|
||||
/** 离屏缓冲Bitmap（存储历史笔迹） */
|
||||
private var offscreenBitmap: android.graphics.Bitmap? = null
|
||||
private var offscreenCanvas: Canvas? = null
|
||||
|
||||
/** 渲染线程 */
|
||||
private var renderThread: RenderThread? = null
|
||||
|
||||
/** Surface是否可用 */
|
||||
private var surfaceReady = false
|
||||
|
||||
/** 画布宽高 */
|
||||
private var canvasWidth = 0
|
||||
private var canvasHeight = 0
|
||||
|
||||
/** 缩放和平移参数（遥控器控制） */
|
||||
private var scaleX = 1.0f
|
||||
private var scaleY = 1.0f
|
||||
private var translateX = 0.0f
|
||||
private var translateY = 0.0f
|
||||
|
||||
/** 绘制用Paint对象（复用避免GC） */
|
||||
private val strokePaint = Paint().apply {
|
||||
isAntiAlias = true
|
||||
style = Paint.Style.STROKE
|
||||
strokeCap = Paint.Cap.ROUND
|
||||
strokeJoin = Paint.Join.ROUND
|
||||
}
|
||||
|
||||
private val backgroundPaint = Paint().apply {
|
||||
color = Color.WHITE
|
||||
style = Paint.Style.FILL
|
||||
}
|
||||
|
||||
/** 复用Path对象 */
|
||||
private val reusablePath = Path()
|
||||
|
||||
/** 是否需要刷新离屏缓冲 */
|
||||
private var needsRefreshOffscreen = false
|
||||
|
||||
init {
|
||||
holder.addCallback(this)
|
||||
// 设置透明背景（支持叠加在课件内容上方）
|
||||
setZOrderOnTop(false)
|
||||
}
|
||||
|
||||
/* ========== SurfaceHolder.Callback ========== */
|
||||
|
||||
override fun surfaceCreated(holder: SurfaceHolder) {
|
||||
surfaceReady = true
|
||||
canvasWidth = holder.surfaceFrame.width()
|
||||
canvasHeight = holder.surfaceFrame.height()
|
||||
|
||||
// 创建离屏缓冲（与Surface同尺寸）
|
||||
offscreenBitmap = android.graphics.Bitmap.createBitmap(
|
||||
canvasWidth, canvasHeight, android.graphics.Bitmap.Config.ARGB_8888
|
||||
)
|
||||
offscreenCanvas = Canvas(offscreenBitmap!!)
|
||||
offscreenCanvas?.drawRect(0f, 0f, canvasWidth.toFloat(), canvasHeight.toFloat(), backgroundPaint)
|
||||
|
||||
// 启动渲染线程
|
||||
renderThread = RenderThread()
|
||||
renderThread?.start()
|
||||
|
||||
// 如果已有历史笔迹数据，先渲染到离屏缓冲
|
||||
if (completedStrokes.isNotEmpty()) {
|
||||
rebuildOffscreenCache()
|
||||
}
|
||||
|
||||
Log.i(TAG, "Surface创建完成: ${canvasWidth}x${canvasHeight}")
|
||||
}
|
||||
|
||||
override fun surfaceChanged(holder: SurfaceHolder, format: Int, width: Int, height: Int) {
|
||||
canvasWidth = width
|
||||
canvasHeight = height
|
||||
// 重建离屏缓冲以匹配新尺寸
|
||||
offscreenBitmap?.recycle()
|
||||
offscreenBitmap = android.graphics.Bitmap.createBitmap(
|
||||
width, height, android.graphics.Bitmap.Config.ARGB_8888
|
||||
)
|
||||
offscreenCanvas = Canvas(offscreenBitmap!!)
|
||||
rebuildOffscreenCache()
|
||||
Log.i(TAG, "Surface尺寸变化: ${width}x${height}")
|
||||
}
|
||||
|
||||
override fun surfaceDestroyed(holder: SurfaceHolder) {
|
||||
surfaceReady = false
|
||||
renderThread?.stopRendering()
|
||||
renderThread = null
|
||||
offscreenBitmap?.recycle()
|
||||
offscreenBitmap = null
|
||||
Log.i(TAG, "Surface已销毁")
|
||||
}
|
||||
|
||||
/* ========== 公开API ========== */
|
||||
|
||||
/**
|
||||
* 添加笔迹点（由WebSocket接收器调用）
|
||||
* @param studentId 学生标识
|
||||
* @param point 坐标点
|
||||
* @param isPenDown true=落笔（笔画开始），false=行笔中
|
||||
*/
|
||||
fun addStrokePoint(studentId: String, point: StrokePoint, isPenDown: Boolean) {
|
||||
if (isPenDown) {
|
||||
// 新建笔画
|
||||
val color = StudentColorPalette.getColorForStudent(studentId)
|
||||
val stroke = Stroke(studentId = studentId, color = color)
|
||||
stroke.points.add(point)
|
||||
activeStrokes[studentId] = stroke
|
||||
} else {
|
||||
// 添加到当前活跃笔画
|
||||
activeStrokes[studentId]?.points?.add(point)
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* 完成一个笔画（抬笔事件）
|
||||
* 将活跃笔画移入已完成列表，并渲染到离屏缓冲
|
||||
*/
|
||||
fun finishStroke(studentId: String) {
|
||||
val stroke = activeStrokes.remove(studentId) ?: return
|
||||
if (stroke.points.size >= 2) {
|
||||
completedStrokes.add(stroke)
|
||||
// 将新完成的笔画绘制到离屏缓冲
|
||||
offscreenCanvas?.let { canvas ->
|
||||
drawSingleStroke(canvas, stroke)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/** 清除所有笔迹 */
|
||||
fun clearAll() {
|
||||
completedStrokes.clear()
|
||||
activeStrokes.clear()
|
||||
offscreenCanvas?.drawRect(0f, 0f, canvasWidth.toFloat(), canvasHeight.toFloat(), backgroundPaint)
|
||||
Log.i(TAG, "所有笔迹已清除")
|
||||
}
|
||||
|
||||
/** 清除指定学生的笔迹 */
|
||||
fun clearStudentStrokes(studentId: String) {
|
||||
activeStrokes.remove(studentId)
|
||||
completedStrokes.removeAll { it.studentId == studentId }
|
||||
rebuildOffscreenCache()
|
||||
}
|
||||
|
||||
/** 设置显示缩放（遥控器方向键操作） */
|
||||
fun setZoom(scale: Float) {
|
||||
scaleX = scale.coerceIn(0.5f, 5.0f)
|
||||
scaleY = scaleX
|
||||
}
|
||||
|
||||
/** 设置显示平移 */
|
||||
fun setPan(dx: Float, dy: Float) {
|
||||
translateX += dx
|
||||
translateY += dy
|
||||
}
|
||||
|
||||
/* ========== 渲染逻辑 ========== */
|
||||
|
||||
/** 重建离屏缓冲（将所有已完成笔画重新绘制） */
|
||||
private fun rebuildOffscreenCache() {
|
||||
val canvas = offscreenCanvas ?: return
|
||||
canvas.drawRect(0f, 0f, canvasWidth.toFloat(), canvasHeight.toFloat(), backgroundPaint)
|
||||
for (stroke in completedStrokes) {
|
||||
drawSingleStroke(canvas, stroke)
|
||||
}
|
||||
Log.d(TAG, "离屏缓冲重建完成，笔画数: ${completedStrokes.size}")
|
||||
}
|
||||
|
||||
/**
|
||||
* 绘制单个笔画（贝塞尔平滑 + 压力笔锋）
|
||||
* 采用分段绘制策略：每两个相邻点之间用三次贝塞尔曲线连接
|
||||
*/
|
||||
private fun drawSingleStroke(canvas: Canvas, stroke: Stroke) {
|
||||
val points = stroke.points
|
||||
if (points.size < 2) return
|
||||
|
||||
strokePaint.color = stroke.color
|
||||
|
||||
for (i in 1 until points.size) {
|
||||
val prev = points[i - 1]
|
||||
val curr = points[i]
|
||||
|
||||
// 根据压力计算笔画宽度（笔锋效果）
|
||||
val width = calculateStrokeWidth(
|
||||
stroke.baseWidth, prev.pressure, curr.pressure,
|
||||
i, points.size
|
||||
)
|
||||
strokePaint.strokeWidth = width * MM_TO_PX
|
||||
|
||||
if (i >= 2 && i < points.size) {
|
||||
// 三次贝塞尔曲线平滑
|
||||
val pp = points[i - 2]
|
||||
val cp1x = prev.x * MM_TO_PX + (curr.x - pp.x) * MM_TO_PX * BEZIER_TENSION
|
||||
val cp1y = prev.y * MM_TO_PX + (curr.y - pp.y) * MM_TO_PX * BEZIER_TENSION
|
||||
val cp2x = curr.x * MM_TO_PX - (curr.x - prev.x) * MM_TO_PX * BEZIER_TENSION
|
||||
val cp2y = curr.y * MM_TO_PX - (curr.y - prev.y) * MM_TO_PX * BEZIER_TENSION
|
||||
|
||||
reusablePath.reset()
|
||||
reusablePath.moveTo(prev.x * MM_TO_PX, prev.y * MM_TO_PX)
|
||||
reusablePath.cubicTo(cp1x, cp1y, cp2x, cp2y, curr.x * MM_TO_PX, curr.y * MM_TO_PX)
|
||||
canvas.drawPath(reusablePath, strokePaint)
|
||||
} else {
|
||||
// 前两个点直接连线
|
||||
canvas.drawLine(
|
||||
prev.x * MM_TO_PX, prev.y * MM_TO_PX,
|
||||
curr.x * MM_TO_PX, curr.y * MM_TO_PX,
|
||||
strokePaint
|
||||
)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* 计算压力感应笔画宽度
|
||||
* 模拟真实书写笔锋：落笔由细变粗，行笔随压力变化，抬笔由粗变细
|
||||
*/
|
||||
private fun calculateStrokeWidth(
|
||||
baseWidth: Float,
|
||||
prevPressure: Float,
|
||||
currPressure: Float,
|
||||
index: Int,
|
||||
totalPoints: Int
|
||||
): Float {
|
||||
val avgPressure = (prevPressure + currPressure) / 2.0f
|
||||
|
||||
// 基础宽度根据压力缩放（0.3x - 2.0x）
|
||||
var width = baseWidth * (0.3f + avgPressure * 1.7f)
|
||||
|
||||
// 落笔过渡效果（前N个点逐渐增加宽度）
|
||||
if (index < PEN_DOWN_TRANSITION) {
|
||||
width *= (index.toFloat() / PEN_DOWN_TRANSITION)
|
||||
}
|
||||
|
||||
// 抬笔过渡效果（最后N个点逐渐减小宽度）
|
||||
val remaining = totalPoints - index
|
||||
if (remaining < PEN_UP_TRANSITION) {
|
||||
width *= (remaining.toFloat() / PEN_UP_TRANSITION)
|
||||
}
|
||||
|
||||
return max(width, 0.5f)
|
||||
}
|
||||
|
||||
/* ========== 渲染线程 ========== */
|
||||
|
||||
/**
|
||||
* 渲染线程 - 以60fps目标帧率循环渲染
|
||||
* 每帧将离屏缓冲绘制到Surface，然后叠加活跃笔画
|
||||
*/
|
||||
inner class RenderThread : Thread("StrokeRenderThread") {
|
||||
|
||||
@Volatile
|
||||
private var running = true
|
||||
|
||||
fun stopRendering() {
|
||||
running = false
|
||||
}
|
||||
|
||||
override fun run() {
|
||||
Log.i(TAG, "渲染线程启动")
|
||||
|
||||
while (running && surfaceReady) {
|
||||
val frameStart = System.currentTimeMillis()
|
||||
|
||||
try {
|
||||
val canvas = holder.lockCanvas() ?: continue
|
||||
try {
|
||||
// 步骤1：绘制离屏缓冲（历史笔迹）
|
||||
offscreenBitmap?.let { bitmap ->
|
||||
canvas.save()
|
||||
canvas.translate(translateX, translateY)
|
||||
canvas.scale(scaleX, scaleY)
|
||||
canvas.drawBitmap(bitmap, 0f, 0f, null)
|
||||
canvas.restore()
|
||||
}
|
||||
|
||||
// 步骤2：绘制当前活跃笔画（正在书写的）
|
||||
canvas.save()
|
||||
canvas.translate(translateX, translateY)
|
||||
canvas.scale(scaleX, scaleY)
|
||||
for (stroke in activeStrokes.values) {
|
||||
if (stroke.points.size >= 2) {
|
||||
drawSingleStroke(canvas, stroke)
|
||||
}
|
||||
}
|
||||
canvas.restore()
|
||||
} finally {
|
||||
holder.unlockCanvasAndPost(canvas)
|
||||
}
|
||||
} catch (e: Exception) {
|
||||
Log.e(TAG, "渲染帧异常: ${e.message}")
|
||||
}
|
||||
|
||||
// 帧率控制：等待到下一帧时间
|
||||
val elapsed = System.currentTimeMillis() - frameStart
|
||||
val sleepTime = FRAME_INTERVAL_MS - elapsed
|
||||
if (sleepTime > 0) {
|
||||
try {
|
||||
sleep(sleepTime)
|
||||
} catch (_: InterruptedException) {
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
Log.i(TAG, "渲染线程已停止")
|
||||
}
|
||||
}
|
||||
|
||||
/** 释放资源 */
|
||||
fun release() {
|
||||
renderThread?.stopRendering()
|
||||
renderThread = null
|
||||
offscreenBitmap?.recycle()
|
||||
offscreenBitmap = null
|
||||
completedStrokes.clear()
|
||||
activeStrokes.clear()
|
||||
Log.i(TAG, "渲染器资源已释放")
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user