添加非线性颜色过滤

app/src/main/assets/shaders/texture.frag

@@ -6,26 +6,40 @@ layout (binding = 2) uniform sampler2D samplerColor_ex;
 layout (location = 0) in vec2 inUV;
 layout (location = 1) in vec3 inNormal;
 
-
 layout (location = 0) out vec4 outFragColor;
 
 void main() 
 {
-	vec4 color = texture(samplerColor, inUV);
+    vec4 color = texture(samplerColor, inUV);
-	vec4 color_ex = texture(samplerColor_ex, inUV);
+    vec4 color_ex = texture(samplerColor_ex, inUV);
 
-	vec3 N = normalize(inNormal);
+    vec3 N = normalize(inNormal);
 
-	vec4 textureColor = color;
+    // 计算与 (0,0,1) 的点乘
-
-	// 计算与 (0,0,1) 的点乘
     float ndot = dot(N, vec3(0.0, 0.0, -1.0));
 
-	// 保证结果 >= 0
+    // 保证结果 >= 0
     ndot = max(ndot, 0.0);
     
-	vec4 blendedColor = mix(color_ex, color, ndot);
+    // 重新映射ndot值，让中间2/3部分进行融合
+    // 当ndot在[0.166, 0.833]范围内时进行混合，两端保持不变
+    float blendFactor;
+    if (ndot < 0.166) {
+        blendFactor = 0.0; // 完全使用color_ex
+    } else if (ndot > 0.833) {
+        blendFactor = 1.0; // 完全使用color
+    } else {
+        // 在中间2/3部分进行平滑过渡
+        blendFactor = (ndot - 0.166) / (0.833 - 0.166);
+    }
 
-	outFragColor = blendedColor;
+	// 使用smoothstep创建中间2/3的融合区域
+    // 参数说明：smoothstep(edge0, edge1, x)
+    // 当x < edge0时返回0，当x > edge1时返回1，在中间时平滑过渡
+    //float blendFactor = smoothstep(0.166, 0.833, ndot);
     
+    
+    vec4 blendedColor = mix(color_ex, color, blendFactor);
+
+    outFragColor = blendedColor;
 }