小程序源码 辅助类库 opengl绘制飘动的国旗效果源码.rar

package org.android.demo; import java.nio.FloatBuffer; import java.nio.IntBuffer; import java.nio.ShortBuffer; import javax.microedition.khronos.opengles.GL10; import android.graphics.Bitmap; import android.opengl.GLUtils; /** * @see 绘制用到的通用方法 * @author (虾米吃鱼肉干) * */ public class MyUtil { private final static float PI = (float) Math.PI; public static float DEPTH = -3.0f;// 深度 public static int NUMBER = 40;// 网格数量Num*Num int[] mTextures;// 纹理标识数组 float[] mBase = new float[3];// 原点偏移量 private static float dx;// 单位x坐标 private static float dy;// 单位y坐标 private static float tx;// 单位纹理坐标 private static float angle;// 单位角度 private float mVertexsArray[][][] = new float[NUMBER][NUMBER][3];// 顶点坐标数组 private float mTexCoordsArray[][][] = new float[NUMBER][NUMBER][2];// 纹理坐标数组 private float mNormalsArray[][][] = new float[NUMBER][NUMBER][3];// 法向量坐标数组 private short mOrderArray[] = new short[(NUMBER - 1) * (NUMBER - 1) * 4];// 绘制顺序数组 FloatBuffer mVertexBuffer;// 顶点 FloatBuffer mTexCoordsBuffer;// 纹理 FloatBuffer mNormalsBuffer;// 法向量 ShortBuffer mOrderBuffer;// 绘制顺序 int rot = 0;// 旋转角度 int k = 0;// float d;// 深度中间缓存 /** * @see 初始化顶点信息、纹理信息、顶点法向量信息、顶点顺序信息 */ public MyUtil() { super(); initInfo(); generationPoints(); getPointBuffer(); getTexCoordsBuffer(); getNormals(); getNormalsBuffer(); getOrder(); } /** * @see 设置网格密度 n*n * @param n */ public void setNum(int n) { NUMBER = n; } /** * @see 设置坐标深度值 * @param d */ public void setDepth(float d) { DEPTH = d; } /** * @see 初始化单位值 */ private void initInfo() { // 5 3.35 dx = 3.0f / (NUMBER - 1); dy = 2.0f / (NUMBER - 1); tx = 1.0f / (NUMBER - 1); angle = ((2 * PI) / (NUMBER - 1)); mBase[0] = 0; mBase[1] = 0; mBase[2] = DEPTH; } /** * @see 生成顶点坐标与纹理坐标 */ public void generationPoints() { for (int i = 0; i < NUMBER; i++) { d = getDepth(i); for (int j = 0; j < NUMBER; j++) { mVertexsArray[i][j][0] = i * dx - NUMBER * dx / 2; mVertexsArray[i][j][1] = NUMBER * dy / 2 - j * dy; mVertexsArray[i][j][2] = d; mTexCoordsArray[i][j][0] = i * tx; mTexCoordsArray[i][j][1] = (NUMBER - 1 - j) * tx; } } } /** * @see 计算深度值根据正弦曲线规律 * @param i * @return */ public float getDepth(int i) { return (DEPTH + (float) Math.sin(2 * i * angle)) * 0.05f * Math.abs(DEPTH); } /** * @see 得到绘制顶点顺序buffer */ private void getOrder() { for (int i = 0; i < NUMBER - 1; i++) { for (int j = 0; j < NUMBER - 1; j++) { mOrderArray[(i * (NUMBER - 1) + j) * 4 + 0] = (short) (i * NUMBER + j); mOrderArray[(i * (NUMBER - 1) + j) * 4 + 1] = (short) ((i + 1) * NUMBER + j); mOrderArray[(i * (NUMBER - 1) + j) * 4 + 2] = (short) (i * NUMBER + j + 1); mOrderArray[(i * (NUMBER - 1) + j) * 4 + 3] = (short) ((i + 1) * NUMBER + j + 1); } } mOrderBuffer = ShortBuffer.wrap(mOrderArray); } /** * @see 得到顶点buffer */ private void getPointBuffer() { float vertex[] = new float[NUMBER * NUMBER * 3]; for (int i = 0; i < NUMBER; i++) { for (int j = 0; j < NUMBER; j++) { for (int k = 0; k < 3; k++) { vertex[(i * NUMBER + j) * 3 + k] = mVertexsArray[i][j][k]; } } } mVertexBuffer = FloatBuffer.wrap(vertex); } /** * @see 得到纹理buffer */ private void getTexCoordsBuffer() { float texCoord[] = new float[NUMBER * NUMBER * 2]; for (int i = 0; i < NUMBER; i++) { for (int j = 0; j < NUMBER; j++) { for (int k = 0; k < 2; k++) { texCoord[(i * NUMBER + (NUMBER - 1 - j)) * 2 + k] = mTexCoordsArray[i][j][k]; } } } mTexCoordsBuffer = FloatBuffer.wrap(texCoord); } /** * @see 1得到法向量buffer */ private void getNormalsBuffer() { float normal[] = new float[NUMBER * NUMBER * 3]; for (int i = 0; i < NUMBER; i++) { for (int j = 0; j < NUMBER; j++) { for (int k = 0; k < 3; k++) { normal[(i * NUMBER + j) * 3 + k] = mNormalsArray[i][j][k]; } } } mNormalsBuffer = FloatBuffer.wrap(normal); } /** * @see 2计算出顶点法向量坐标 */ private void getNormals() { float[] nor = new float[3];// 三个顶点 for (int i = 0; i < NUMBER; i++) { nor = getVertexsNormal(i, 1); for (int j = 0; j < NUMBER; j++) { mNormalsArray[i][j][0] = nor[0]; mNormalsArray[i][j][1] = nor[1]; mNormalsArray[i][j][2] = nor[2]; } } } /** * @see 3计算顶点法向量 * @param i * @param j * @return */ private float[] getVertexsNormal(int i, int j) { float[] nor1 = new float[3]; float[] nor2 = new float[3]; float[] nor3 = new float[3]; float[] nor4 = new float[3]; float[] temp = new float[] { 0, 0, -1.0f, }; if (i - 1 < 0 || j - 1 < 0) { nor1 = temp; } else { nor1 = getNormalFrom3Vertexs(new float[] { mVertexsArray[i][j - 1][0], mVertexsArray[i][j - 1][1], mVertexsArray[i][j - 1][2] }, new float[] { mVertexsArray[i - 1][j][0], mVertexsArray[i - 1][j][1], mVertexsArray[i - 1][j][2] }, new float[] { mVertexsArray[i][j][0], mVertexsArray[i][j][1], mVertexsArray[i][j][2] }); } if (j - 1 < 0 || i + 1 == NUMBER) { nor2 = temp; } else { nor2 = getNormalFrom3Vertexs(new float[] { mVertexsArray[i + 1][j][0], mVertexsArray[i + 1][j][1], mVertexsArray[i + 1][j][2] }, new float[] { mVertexsArray[i][j - 1][0], mVertexsArray[i][j - 1][1], mVertexsArray[i][j - 1][2] }, new float[] { mVertexsArray[i][j][0], mVertexsArray[i][j][1], mVertexsArray[i][j][2] }); } if (i - 1 < 0 || j + 1 == NUMBER) { nor3 = temp; } else { nor3 = getNormalFrom3Vertexs(new float[] { mVertexsArray[i][j][0], mVertexsArray[i][j][1], mVertexsArray[i][j][2] }, new float[] { mVertexsArray[i - 1][j][0], mVertexsArray[i - 1][j][1], mVertexsArray[i - 1][j][2] }, new float[] { mVertexsArray[i][j + 1][0], mVertexsArray[i][j + 1][1], mVertexsArray[i][j + 1][2] }); } if (i + 1 == NUMBER || j + 1 == NUMBER) { nor4 = temp; } else { nor4 = getNormalFrom3Vertexs(new float[] { mVertexsArray[i + 1][j][0], mVertexsArray[i + 1][j][1], mVertexsArray[i + 1][j][2] }, new float[] { mVertexsArray[i][j][0], mVertexsArray[i][j][1], mVertexsArray[i][j][2] }, new float[] { mVertexsArray[i][j + 1][0], mVertexsArray[i][j + 1][1], mVertexsArray[i][j + 1][2] }); } return getNormalFrom4Normals(nor1, nor2, nor3, nor4); } /** * @see 4根据每个顶点相邻的4个三角形计算出该顶点的法向量 * @param nor1 * @param nor2 * @param nor3 * @param nor4 * @return */ private float[] getNormalFrom4Normals(float[] nor1, float[] nor2, float[] nor3, float[] nor4) { float nor[] = new float[3]; nor[0] = nor1[0] + nor2[0] + nor3[0] + nor4[0]; nor[1] = nor1[1] + nor2[1] + nor3[1] + nor4[1]; nor[2] = nor1[2] + nor2[2] + nor3[2] + nor4[2]; return unitNormal(nor); } /** * @see 5通过三个顶点计算该三角形的平面法向量 * @param v1 * @param v2 * @param v3 */ private float[] getNormalFrom3Vertexs(float[] v1, float[] v2, float[] v3) { float a0 = 0, a1 = 0, a2 = 0, b0 = 0, b1 = 0, b2 = 0; float nor[] = new float[3]; a0 = v2[0] - v1[0]; a1 = v2[1] - v1[1]; a2 = v2[2] - v1[2]; b0 = v3[0] - v2[0]; b1 = v3[1] - v2[1]; b2 = v3[2] - v2[2]; nor[0] = a1 * b