feat: 优化 arc3d 的shader 计算，清理多余的 varying 变量

packages/layers/src/line/shaders/line_arc_3d_frag.glsl

@@ -7,9 +7,8 @@ uniform float u_opacity;
 uniform float u_textureBlend;
 uniform float u_blur : 0.9;
 uniform float u_line_type: 0.0;
-varying vec2 v_normal;
+// varying vec2 v_normal;
 varying vec4 v_dash_array;
-varying float v_distance_ratio;
 varying vec4 v_color;
 
 uniform float u_line_texture: 0.0;
@@ -17,10 +16,9 @@ uniform sampler2D u_texture;
 uniform vec2 u_textSize;
 varying float v_segmentIndex;
 uniform float segmentNumber;
-varying float v_arcDistrance;
-varying float v_pixelLen;
-varying float v_a;
-varying vec2 v_offset;
+
+varying vec4 v_dataset; // 数据集
+
 varying vec2 v_iconMapUV;
 
 uniform float u_time;
@@ -37,6 +35,7 @@ varying mat4 styleMappingMat;
 void main() {
   float opacity = styleMappingMat[0][0];
   float animateSpeed = 0.0; // 运动速度
+  float d_distance_ratio = v_dataset.g; // 当前点位距离占线总长的比例
 
   if(u_linearColor == 1.0) { // 使用渐变颜色
     gl_FragColor = mix(u_sourceColor, u_targetColor, v_segmentIndex/segmentNumber);
@@ -49,7 +48,7 @@ void main() {
   gl_FragColor.a *= opacity;
   if(u_line_type == LineTypeDash) {
    float flag = 0.;
-    float dashLength = mod(v_distance_ratio, v_dash_array.x + v_dash_array.y + v_dash_array.z + v_dash_array.w);
+    float dashLength = mod(d_distance_ratio, v_dash_array.x + v_dash_array.y + v_dash_array.z + v_dash_array.w);
     if(dashLength < v_dash_array.x || (dashLength > (v_dash_array.x + v_dash_array.y) && dashLength <  v_dash_array.x + v_dash_array.y + v_dash_array.z)) {
       flag = 1.;
     }
@@ -58,7 +57,7 @@ void main() {
 
   if(u_aimate.x == Animate) {
       animateSpeed = u_time / u_aimate.y;
-      float alpha =1.0 - fract( mod(1.0- v_distance_ratio, u_aimate.z)* (1.0/ u_aimate.z) + u_time / u_aimate.y);
+      float alpha =1.0 - fract( mod(1.0- d_distance_ratio, u_aimate.z)* (1.0/ u_aimate.z) + u_time / u_aimate.y);
 
       alpha = (alpha + u_aimate.w -1.0) / u_aimate.w;
       // alpha = smoothstep(0., 1., alpha);
@@ -69,15 +68,15 @@ void main() {
   if(u_line_texture == LineTexture && u_line_type != LineTypeDash) { // while load texture
     // float arcRadio = smoothstep( 0.0, 1.0, (v_segmentIndex / segmentNumber));
     float arcRadio = v_segmentIndex / (segmentNumber - 1.0);
-    float count = floor(v_arcDistrance/v_pixelLen);
+    float count = v_dataset.b; // // 贴图在弧线上重复的数量
 
     float u = fract(arcRadio * count - animateSpeed * count);
  
     if(u_aimate.x == Animate) {
       u = gl_FragColor.a/opacity;
     }
-    float v = length(v_offset)/(v_a); // 横向
 
+    float v = v_dataset.a;  // 线图层贴图部分的 v 坐标值
     vec2 uv= v_iconMapUV / u_textSize + vec2(u, v) / u_textSize * 64.;
     vec4 pattern = texture2D(u_texture, uv);
 

packages/layers/src/line/shaders/line_arc_3d_vert.glsl

@@ -12,8 +12,7 @@ uniform mat4 u_Mvp;
 uniform float segmentNumber;
 uniform vec4 u_aimate: [ 0, 2., 1.0, 0.2 ];
 varying vec4 v_color;
-varying vec2 v_normal;
-varying float v_distance_ratio;
+// varying vec2 v_normal;
 uniform float u_line_type: 0.0;
 uniform vec4 u_dash_array: [10.0, 5., 0, 0];
 varying vec4 v_dash_array;
@@ -21,10 +20,9 @@ varying vec4 v_dash_array;
 uniform float u_icon_step: 100;
 uniform float u_line_texture: 0.0;
 varying float v_segmentIndex;
-varying float v_arcDistrance;
-varying float v_pixelLen;
-varying float v_a;
-varying vec2 v_offset;
+
+varying vec4 v_dataset; // 数据集
+
 attribute vec2 a_iconMapUV;
 varying vec2 v_iconMapUV;
 
@@ -114,8 +112,9 @@ void main() {
   float segmentRatio = getSegmentRatio(segmentIndex);
   float indexDir = mix(-1.0, 1.0, step(segmentIndex, 0.0));
 
+  float d_distance_ratio;
    if(u_line_type == LineTypeDash) {
-    v_distance_ratio = segmentIndex / segmentNumber;
+    d_distance_ratio = segmentIndex / segmentNumber;
     // float total_Distance = pixelDistance(a_Instance.rg, a_Instance.ba) / 2.0 * PI;
     vec2 s = source;
     vec2 t = target;
@@ -128,24 +127,29 @@ void main() {
     v_dash_array = pow(2.0, 20.0 - u_Zoom) * u_dash_array / (total_Distance / segmentNumber * segmentIndex);
   }
     if(u_aimate.x == Animate) {
-      v_distance_ratio = segmentIndex / segmentNumber;
+      d_distance_ratio = segmentIndex / segmentNumber;
   }
+  v_dataset.g = d_distance_ratio; // 当前点位距离占线总长的比例
 
   float nextSegmentRatio = getSegmentRatio(segmentIndex + indexDir);
   vec3 curr = getPos(source, target, segmentRatio);
   vec3 next = getPos(source, target, nextSegmentRatio);
   vec2 offset = getExtrusionOffset((next.xy - curr.xy) * indexDir, a_Position.y);
-  v_normal = getNormal((next.xy - curr.xy) * indexDir, a_Position.y);
+  // v_normal = getNormal((next.xy - curr.xy) * indexDir, a_Position.y);
 
 
   v_segmentIndex = a_Position.x;
   if(LineTexture == u_line_texture && u_line_type != LineTypeDash) { // 开启贴图模式  
-    v_arcDistrance = length(source - target);
-    v_pixelLen = project_pixel(u_icon_step);
+
+    float arcDistrance = length(source - target);
+    float pixelLen =  project_pixel(u_icon_step);
+    v_dataset.b = floor(arcDistrance/pixelLen); // 贴图在弧线上重复的数量
 
     vec2 projectOffset = project_pixel(offset);
-    v_offset = projectOffset + projectOffset * sign(a_Position.y);
-    v_a = project_pixel(a_Size);
+    float lineOffsetWidth = length(projectOffset + projectOffset * sign(a_Position.y)); // 线横向偏移的距离
+    float linePixelSize = project_pixel(a_Size);  // 定点位置偏移，按地图等级缩放后的距离
+    v_dataset.a = lineOffsetWidth/linePixelSize; // 线图层贴图部分的 v 坐标值
+
     v_iconMapUV = a_iconMapUV;
   }
   

packages/layers/src/line/shaders/line_frag.glsl

@@ -69,7 +69,7 @@ void main() {
     float aDistance = v_dataset.g;      // 当前顶点的距离
     float d_texPixelLen = v_dataset.b;  // 贴图的像素长度，根据地图层级缩放
     float u = fract(mod(aDistance, d_texPixelLen)/d_texPixelLen - animateSpeed);
-    float v = v_dataset.a;
+    float v = v_dataset.a;  // 线图层贴图部分的 v 坐标值
 
     v = max(smoothstep(0.95, 1.0, v), v);
     vec2 uv= v_iconMapUV / u_textSize + vec2(u, v) / u_textSize * 64.;

packages/layers/src/line/shaders/line_vert.glsl

@@ -99,7 +99,7 @@ void main() {
   v_dataset.r = d_distance_ratio; // 当前点位距离占线总长的比例
   v_dataset.g = a_Distance;       // 当前顶点的距离
   v_dataset.b = d_texPixelLen;    // 贴图的像素长度，根据地图层级缩放
-  v_dataset.a = texV;
+  v_dataset.a = texV;             // 线图层贴图部分的 v 坐标值
 
   vec4 project_pos = project_position(vec4(a_Position.xy, 0, 1.0));