From 1c2e61126b6e098e0d2930c91181fff58ebc0fe8 Mon Sep 17 00:00:00 2001
From: fuzhenn <fuzhen@maptalks.org>
Date: Fri, 5 Sep 2025 16:30:38 +0800
Subject: [PATCH 1/4] add terrain mask specs

---
 debug/gl/terrain-mask.html                    |  15 +++---
 .../gl/src/layer/terrain/TerrainLitPainter.js |  10 +++-
 .../reshader.gl/src/pbr/glsl/standard.vert    |   7 ++-
 .../src/pbr/wgsl/standard_vert.wgsl           |   6 ++-
 .../src/shaderlib/glsl/output.vert            |  15 +++++-
 .../src/shaderlib/wgsl/common_pack_float.ts   |  28 ++++++++++
 .../reshader.gl/src/shaderlib/wgsl/output.ts  |  14 +++++
 .../vt/src/layer/layer/VectorTileLayer.ts     |   3 ++
 .../terrain/terrain-lit-mask/expected.png     | Bin 0 -> 9467 bytes
 .../terrain/terrain-lit-mask/index.js         |  49 ++++++++++++++++++
 .../terrain/terrain-mask/expected.png         | Bin 0 -> 1508 bytes
 .../fixtures/terrain/terrain-mask/index.js    |  48 +++++++++++++++++
 packages/vt/test/integration/terrain.spec.js  |  15 +++++-
 13 files changed, 198 insertions(+), 12 deletions(-)
 create mode 100644 packages/vt/test/integration/fixtures/terrain/terrain-lit-mask/expected.png
 create mode 100644 packages/vt/test/integration/fixtures/terrain/terrain-lit-mask/index.js
 create mode 100644 packages/vt/test/integration/fixtures/terrain/terrain-mask/expected.png
 create mode 100644 packages/vt/test/integration/fixtures/terrain/terrain-mask/index.js

diff --git a/debug/gl/terrain-mask.html b/debug/gl/terrain-mask.html
index f96c2c79d7..15318de935 100644
--- a/debug/gl/terrain-mask.html
+++ b/debug/gl/terrain-mask.html
@@ -31,6 +31,7 @@
         "zoom": 13,
         "pitch": 10,
         "bearing": 0,
+        renderer: 'gl',
         queryTerrainInMapEvents: false
       });
 
@@ -51,6 +52,7 @@
 
       const terrain = {
         debug: true,
+        shader: 'lit',
         type: "mapbox",
         urlTemplate: `https://{s}.tiles.mapbox.com/v4/mapbox.terrain-rgb/{z}/{x}/{y}.pngraw?access_token=${token}`,
         subdomains: ["a", "b", "c", "d"]
@@ -65,11 +67,11 @@
                     type: "Polygon",
                     coordinates: [
                         [
-                            [94.50812103, 29.45095163, 3000],
-                            [94.59012103, 29.45095163, 3000],
-                            [94.59012103, 29.40095163, 3000],
-                            [94.50812103, 29.40095163, 3000],
-                            [94.50812103, 29.45095163, 3000]
+                            [94.50812103, 29.45095163, 0],
+                            [94.59012103, 29.45095163, 0],
+                            [94.59012103, 29.40095163, 0],
+                            [94.50812103, 29.40095163, 0],
+                            [94.50812103, 29.45095163, 0]
                         ]
                     ]
                 },
@@ -99,11 +101,10 @@
             renderPlugin: {
               dataConfig: {
                 type: "fill",
+                altitudeOffset: 3000
               },
               sceneConfig: {},
               type: "terrain-flat-mask",
-            },
-            symbol: {
             }
         }
       ]
diff --git a/packages/gl/src/layer/terrain/TerrainLitPainter.js b/packages/gl/src/layer/terrain/TerrainLitPainter.js
index 1e98fdaa27..6d0f645e24 100644
--- a/packages/gl/src/layer/terrain/TerrainLitPainter.js
+++ b/packages/gl/src/layer/terrain/TerrainLitPainter.js
@@ -105,11 +105,16 @@ class TerrainLitPainter extends TerrainPainter {
         const material = new reshader.pbr.StandardMaterial(matInfo);
         const mesh = new reshader.Mesh(geo, material);
         mesh.properties.matVer = this._matVer;
+        if (!mesh.uniforms.flatMask) {
+            const emptyTexture = this.getEmptyTexture();
+            mesh.setUniform('flatMask', emptyTexture);
+        }
         const defines = mesh.defines;
         defines['HAS_UV_FLIP'] = 1;
         defines['HAS_TERRAIN_NORMAL'] = 1;
         defines['HAS_MAP'] = 1;
         defines['HAS_LAYER_OPACITY'] = 1;
+        defines['HAS_TERRAIN_FLAT_MASK'] = 1;
         mesh.defines = defines;
         // mesh.setUniform('terrainTileResolution', tileInfo.res);
         this.prepareMesh(mesh, tileInfo, terrainImage);
@@ -126,7 +131,10 @@ class TerrainLitPainter extends TerrainPainter {
                 mesh.properties.matVer = this._matVer;
             }
             if (tileImage.skin) {
-                mesh.material.set('skinTexture', tileImage.skin);
+                mesh.material.set('skinTexture', tileImage.skin.color[0]);
+            }
+            if (tileImage.mask) {
+                mesh.setUniform('flatMask', tileImage.mask.color[0]);
             }
             mesh.setUniform('polygonOpacity', 1.0);
             // const { skirtOffset, skirtCount } = mesh.properties;
diff --git a/packages/reshader.gl/src/pbr/glsl/standard.vert b/packages/reshader.gl/src/pbr/glsl/standard.vert
index 3d1e342aa0..8d56c5ef30 100644
--- a/packages/reshader.gl/src/pbr/glsl/standard.vert
+++ b/packages/reshader.gl/src/pbr/glsl/standard.vert
@@ -4,8 +4,13 @@ precision highp float;
 
 attribute vec3 aPosition;
 
-#if defined(HAS_MAP)
+#if defined(HAS_NORMAL) || defined(HAS_TERRAIN_FLAT_MASK)
     attribute vec2 aTexCoord;
+    #include <common_pack_float>
+#endif
+
+#if defined(HAS_MAP)
+
     uniform vec2 uvOrigin;
     uniform vec2 uvScale;
     uniform vec2 uvOffset;
diff --git a/packages/reshader.gl/src/pbr/wgsl/standard_vert.wgsl b/packages/reshader.gl/src/pbr/wgsl/standard_vert.wgsl
index 51defac84f..702578b99b 100644
--- a/packages/reshader.gl/src/pbr/wgsl/standard_vert.wgsl
+++ b/packages/reshader.gl/src/pbr/wgsl/standard_vert.wgsl
@@ -8,6 +8,7 @@
     #include <fbo_picking_vert>
 #endif
 #include <excavate_vert>
+#include <common_pack_float>
 
 struct VertexInput {
     #ifdef POSITION_IS_INT
@@ -16,8 +17,11 @@ struct VertexInput {
         @location($i) aPosition: vec3f,
     #endif
 
-    #if HAS_MAP
+    #if HAS_MAP || HAS_TERRAIN_FLAT_MASK
         @location($i) aTexCoord: vec2f,
+    #endif
+    #if HAS_MAP
+
         #ifdef HAS_I3S_UVREGION
             @location($i) uvRegion: vec4f,
         #endif
diff --git a/packages/reshader.gl/src/shaderlib/glsl/output.vert b/packages/reshader.gl/src/shaderlib/glsl/output.vert
index c9fcada760..35fe7804d9 100644
--- a/packages/reshader.gl/src/shaderlib/glsl/output.vert
+++ b/packages/reshader.gl/src/shaderlib/glsl/output.vert
@@ -69,7 +69,11 @@ mat4 getPositionMatrix() {
 }
 
 #ifdef HAS_MIN_ALTITUDE
-uniform float minAltitude;
+    uniform float minAltitude;
+#endif
+
+#ifdef HAS_TERRAIN_FLAT_MASK
+    uniform sampler2D flatMask;
 #endif
 
 vec4 getPosition(vec3 aPosition) {
@@ -84,6 +88,15 @@ vec4 getPosition(vec3 aPosition) {
     #ifdef HAS_TERRAIN_ALTITUDE
         POSITION.z += aTerrainAltitude * 100.0;
     #endif
+    #ifdef HAS_TERRAIN_FLAT_MASK
+        vec2 uv = aTexCoord;
+        uv.y = 1.0 - uv.y;
+        vec4 encodedHeight = texture2D(flatMask, uv);
+        if (length(encodedHeight) < 2.0) {
+            float maskHeight = decodeFloat32(encodedHeight);
+            POSITION.z = min(POSITION.z, maskHeight);
+        }
+    #endif
     #ifdef HAS_MIN_ALTITUDE
         POSITION.z += minAltitude * 100.0;
     #endif
diff --git a/packages/reshader.gl/src/shaderlib/wgsl/common_pack_float.ts b/packages/reshader.gl/src/shaderlib/wgsl/common_pack_float.ts
index cb8fefceb5..809133f8cb 100644
--- a/packages/reshader.gl/src/shaderlib/wgsl/common_pack_float.ts
+++ b/packages/reshader.gl/src/shaderlib/wgsl/common_pack_float.ts
@@ -67,6 +67,34 @@ fn common_encodeDepth(depth: f32) -> vec4f {
 fn common_decodeDepth(pack: vec4f) -> f32 {
     return pack.r + pack.g / 255.0;
 }
+
+// https://cloud.tencent.com/developer/ask/sof/103481834
+fn encodeFloat32(f: f32) -> vec4f {
+    var e = 5.0;
+
+    var F = abs(f);
+    var Sign = step(0.0, -f);
+    var Exponent = floor(log2(F));
+    var Mantissa = (exp2(- Exponent) * F);
+    Exponent = floor(log2(F) + 127.0) + floor(log2(Mantissa));
+    var rgba = vec4(0.0);
+    rgba[0] = 128.0 * Sign  + floor(Exponent*exp2(-1.0));
+    rgba[1] = 128.0 * mod(Exponent,2.0) + mod(floor(Mantissa*128.0),128.0);
+    rgba[2] = floor(mod(floor(Mantissa*exp2(23.0 -8.0)),exp2(8.0)));
+    rgba[3] = floor(exp2(23.0)*mod(Mantissa,exp2(-15.0)));
+    return rgba / 255.0;
+}
+
+fn decodeFloat32(rgba: vec4f) -> f32 {
+    rgba *= 255.0;
+    var Sign = 1.0 - step(128.0,rgba[0])*2.0;
+    var Exponent = 2.0 * mod(rgba[0],128.0) + step(128.0,rgba[1]) - 127.0;
+    var Mantissa = mod(rgba[1],128.0)*65536.0 + rgba[2]*256.0 +rgba[3] + float(0x800000);
+    var Result =  Sign * exp2(Exponent) * (Mantissa * exp2(-23.0 ));
+    return Result;
+}
+
+
 `;
 
 const frag = vert;
diff --git a/packages/reshader.gl/src/shaderlib/wgsl/output.ts b/packages/reshader.gl/src/shaderlib/wgsl/output.ts
index ce5d6d108e..169442dd2b 100644
--- a/packages/reshader.gl/src/shaderlib/wgsl/output.ts
+++ b/packages/reshader.gl/src/shaderlib/wgsl/output.ts
@@ -31,6 +31,11 @@ const vert = /* wgsl */`
     @group(0) @binding($b) var<uniform> altitudeUniforms: AltitudeUniforms;
 #endif
 
+#ifdef HAS_TERRAIN_FLAT_MASK
+    @group(0) @binding($b) var flatMask: texture_2d<f32>;
+    @group(0) @binding($b) var flatMaskSampler: sampler;
+#endif
+
 fn getPositionMatrix(input: VertexInput, vertexOutput: ptr<function, VertexOutput>, positionMatrix: mat4x4f) -> mat4x4f {
     var worldMatrix: mat4x4f;
 #ifdef HAS_INSTANCE
@@ -79,6 +84,15 @@ fn getPosition(inputPosition: vec3f, vertexInput: VertexInput) -> vec4f {
     #ifdef HAS_TERRAIN_ALTITUDE
         outputPosition.z += vertexInput.aTerrainAltitude * 100.0;
     #endif
+    #ifdef HAS_TERRAIN_FLAT_MASK
+        var uv = aTexCoord;
+        uv.y = 1.0 - uv.y;
+        let encodedHeight = textureSample(flatMask, flatMaskSampler, uv);
+        if (length(encodedHeight) < 2.0) {
+            float maskHeight = decodeFloat32(encodedHeight);
+            outputPosition.z = min(outputPosition.z, maskHeight);
+        }
+    #endif
     #ifdef HAS_MIN_ALTITUDE
         outputPosition.z += altitudeUniforms.minAltitude * 100.0;
     #endif
diff --git a/packages/vt/src/layer/layer/VectorTileLayer.ts b/packages/vt/src/layer/layer/VectorTileLayer.ts
index 75abdf06e8..2df1806870 100644
--- a/packages/vt/src/layer/layer/VectorTileLayer.ts
+++ b/packages/vt/src/layer/layer/VectorTileLayer.ts
@@ -1291,6 +1291,9 @@ class VectorTileLayer extends maptalks.TileLayer {
       ) {
         throw new Error(`Invalid filter at ${i} : ${JSON.stringify(filter)}`);
       }
+      if (!styles[i].symbol) {
+        styles[i].symbol = {};
+      }
       //TODO 如果定义了renderPlugin就必须定义symbol
     }
   }
diff --git a/packages/vt/test/integration/fixtures/terrain/terrain-lit-mask/expected.png b/packages/vt/test/integration/fixtures/terrain/terrain-lit-mask/expected.png
new file mode 100644
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diff --git a/packages/vt/test/integration/fixtures/terrain/terrain-lit-mask/index.js b/packages/vt/test/integration/fixtures/terrain/terrain-lit-mask/index.js
new file mode 100644
index 0000000000..1e53df74b7
--- /dev/null
+++ b/packages/vt/test/integration/fixtures/terrain/terrain-lit-mask/index.js
@@ -0,0 +1,49 @@
+const data = {
+    type: 'FeatureCollection',
+    features: [
+        { type: 'Feature', geometry: { type: 'Polygon', coordinates: [
+            [[91.14478,29.696272], [91.14778,29.696272], [91.14778,29.690272], [91.14478,29.690272], [91.14478,29.696272]]]
+        }, properties: { type: 1 } }
+    ]
+
+};
+
+const style = [
+    {
+        filter: true,
+        renderPlugin: {
+            type: 'fill',
+            dataConfig: {
+                type: 'fill'
+            }
+        },
+        symbol: {
+            polygonFill: '#f00',
+            polygonOpacity: 0.5
+        }
+    },
+    {
+        filter: true,
+        renderPlugin: {
+            type: 'terrain-flat-mask',
+            dataConfig: {
+                type: 'fill',
+                altitudeOffset: 3500
+            }
+        },
+        symbol: {}
+    }
+];
+
+module.exports = {
+    style,
+    data,
+    lit: true,
+    renderingCount: 10,
+    view: {
+        center: [91.14478,29.708272],
+        zoom: 12,
+        pitch: 20,
+        bearing: 0,
+    }
+};
diff --git a/packages/vt/test/integration/fixtures/terrain/terrain-mask/expected.png b/packages/vt/test/integration/fixtures/terrain/terrain-mask/expected.png
new file mode 100644
index 0000000000000000000000000000000000000000..bbc74133470c6ee85c08b25895e1f344925d3646
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zuZ?;5Xa{#{YfN2-)NC5j7UeV6&|%C9Y<gKp9`q&#E1v}Z>O|CA3{hu%3G6L$?r%9f
z%hk9(7dO#`63P*TCE2K^DRw8oQY4A<Gw=MGuW^noR9JV!602^XU4W@*gcLaowI!Q$
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zAhcc*TluE-M7mr20UaZM3#B+ojkd`u=7a3>=}i|A7T3}7CkgP+_^U!OuLwRrtN{{5
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hB?Elb%Eq#Bnytkw)o4dtkNIsw$civg<udW!e*j_*Vmkl;

literal 0
HcmV?d00001

diff --git a/packages/vt/test/integration/fixtures/terrain/terrain-mask/index.js b/packages/vt/test/integration/fixtures/terrain/terrain-mask/index.js
new file mode 100644
index 0000000000..8ec3ca2026
--- /dev/null
+++ b/packages/vt/test/integration/fixtures/terrain/terrain-mask/index.js
@@ -0,0 +1,48 @@
+const data = {
+    type: 'FeatureCollection',
+    features: [
+        { type: 'Feature', geometry: { type: 'Polygon', coordinates: [
+            [[91.14478,29.696272], [91.14778,29.696272], [91.14778,29.690272], [91.14478,29.690272], [91.14478,29.696272]]]
+        }, properties: { type: 1 } }
+    ]
+
+};
+
+const style = [
+    {
+        filter: true,
+        renderPlugin: {
+            type: 'fill',
+            dataConfig: {
+                type: 'fill'
+            }
+        },
+        symbol: {
+            polygonFill: '#f00',
+            polygonOpacity: 0.5
+        }
+    },
+    {
+        filter: true,
+        renderPlugin: {
+            type: 'terrain-flat-mask',
+            dataConfig: {
+                type: 'fill',
+                altitudeOffset: 3500
+            }
+        },
+        symbol: {}
+    }
+];
+
+module.exports = {
+    style,
+    data,
+    renderingCount: 10,
+    view: {
+        center: [91.14478,29.708272],
+        zoom: 12,
+        pitch: 20,
+        bearing: 0,
+    }
+};
diff --git a/packages/vt/test/integration/terrain.spec.js b/packages/vt/test/integration/terrain.spec.js
index 6c8b1700a1..21a641bb51 100644
--- a/packages/vt/test/integration/terrain.spec.js
+++ b/packages/vt/test/integration/terrain.spec.js
@@ -23,6 +23,8 @@ const DEFAULT_VIEW = {
     }
 };
 
+const TEST_CANVAS = document.createElement('canvas');
+
 describe('vector tile on terrain integration specs', () => {
     let map, container, server;
     const containerSize = 128;
@@ -76,18 +78,29 @@ describe('vector tile on terrain integration specs', () => {
                 fadeAnimation: false
                 // shader: 'lit'
             };
+            if (style.lit) {
+                terrain.shader = 'lit';
+            }
             const group = new GroupGLLayer('group', [layer], { terrain });
             group.addTo(map);
 
+
             const terrainLayer = group.getTerrainLayer();
             let count = 0;
             let ended = false;
             terrainLayer.on('terrainreadyandrender', () => {
                 count++;
-                const canvas = map.getRenderer().canvas;
+                const mapCanvas = map.getRenderer().canvas;
                 const expectedPath = style.expected;
                 if (!ended && count >= limit) {
                     ended = true;
+
+                    const canvas = TEST_CANVAS;
+                    canvas.width = mapCanvas.width;
+                    canvas.height = mapCanvas.height;
+                    const ctx = canvas.getContext('2d');
+                    ctx.drawImage(mapCanvas, 0, 0);
+
                     //比对测试
                     match(canvas, expectedPath, (err, result) => {
                         if (err) {

From ba518ae8c13e0120cbb0a09b9e02c053cf45c8a0 Mon Sep 17 00:00:00 2001
From: fuzhenn <fuzhen@maptalks.org>
Date: Fri, 5 Sep 2025 16:52:32 +0800
Subject: [PATCH 2/4] fixing specs

---
 packages/reshader.gl/src/pbr/glsl/standard.vert | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/reshader.gl/src/pbr/glsl/standard.vert b/packages/reshader.gl/src/pbr/glsl/standard.vert
index 8d56c5ef30..674251014d 100644
--- a/packages/reshader.gl/src/pbr/glsl/standard.vert
+++ b/packages/reshader.gl/src/pbr/glsl/standard.vert
@@ -4,7 +4,7 @@ precision highp float;
 
 attribute vec3 aPosition;
 
-#if defined(HAS_NORMAL) || defined(HAS_TERRAIN_FLAT_MASK)
+#if defined(HAS_MAP) || defined(HAS_TERRAIN_FLAT_MASK)
     attribute vec2 aTexCoord;
     #include <common_pack_float>
 #endif

From e208c5fd3806a5e56f95231746a7e0abf9344767 Mon Sep 17 00:00:00 2001
From: fuzhenn <fuzhen@maptalks.org>
Date: Fri, 5 Sep 2025 17:29:20 +0800
Subject: [PATCH 3/4] fixing specs

---
 packages/vt/test/integration/terrain.spec.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/packages/vt/test/integration/terrain.spec.js b/packages/vt/test/integration/terrain.spec.js
index 21a641bb51..fb14ec4a2b 100644
--- a/packages/vt/test/integration/terrain.spec.js
+++ b/packages/vt/test/integration/terrain.spec.js
@@ -53,6 +53,7 @@ describe('vector tile on terrain integration specs', () => {
                 options.lights = DEFAULT_VIEW.lights;
             }
             options.devicePixelRatio = 1;
+            options.renderer = 'canvas';
 
             const limit = style.renderingCount || 6;
             map = new maptalks.Map(container, options);

From 2f3b7771c35821a6c3f8baf456ec2adfd688628c Mon Sep 17 00:00:00 2001
From: fuzhenn <fuzhen@maptalks.org>
Date: Fri, 5 Sep 2025 18:01:54 +0800
Subject: [PATCH 4/4] fixing specs

---
 packages/vt/test/specs/update.vector.symbol.spec.js | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/packages/vt/test/specs/update.vector.symbol.spec.js b/packages/vt/test/specs/update.vector.symbol.spec.js
index 25d26340fd..9950a72999 100644
--- a/packages/vt/test/specs/update.vector.symbol.spec.js
+++ b/packages/vt/test/specs/update.vector.symbol.spec.js
@@ -73,6 +73,7 @@ describe('vector layers symbol update specs', () => {
             count++;
         });
         let updated = false;
+        let doneCalled = false;
         group.on('layerload', () => {
             if (count >= 1 && !updated) {
                 const pixel = readPixel(layer.getRenderer().canvas, x + 20, y);
@@ -83,11 +84,12 @@ describe('vector layers symbol update specs', () => {
                     markerHeight: 60
                 });
                 updated = true;
-            } else if (updated && count >= 4) {
+            } else if (updated && count >= 4 && !doneCalled) {
                 const pixel = readPixel(renderer.canvas, x + 20, y);
                 //中心点往外40，能读到像素了
                 assert.deepEqual(pixel, [255, 0, 0, 255]);
                 assert(!partialUpdate);
+                doneCalled = true;
                 done();
             }
         });
@@ -123,6 +125,7 @@ describe('vector layers symbol update specs', () => {
         });
         let updated = false;
         let partialUpdate = false;
+        let doneCalled = false;
         layer.on('partialupdate', () => {
             partialUpdate = true;
         });
@@ -151,12 +154,13 @@ describe('vector layers symbol update specs', () => {
                     },
                 ]);
                 updated = true;
-            } else if (updated && count >= 3) {
+            } else if (updated && count >= 3 && !doneCalled) {
                 const pixel = readPixel(renderer.canvas, x + 20, y);
                 assert.deepEqual(pixel, [0, 255, 0, 255]);
                 const pixel1 = readPixel(renderer.canvas, x, y);
                 assert.deepEqual(pixel1, [255, 0, 0, 255]);
                 assert(!partialUpdate);
+                doneCalled = true;
                 done();
             }
         });