add bloom;some treaks

Editor/assets/shaders/BloomBlur.glsl

@@ -21,59 +21,64 @@ layout(location = 0) out vec4 o_Color;
 in vec2 v_TexCoord;
 
 uniform sampler2D u_Texture;
-uniform bool u_Horizontal;
+uniform bool u_Horizontal;   // 未使用，可保留或移除
+uniform bool u_FirstPass;     // 是否进行阈值处理
+uniform float u_Threshold;    // 亮度阈值
 
 void main()
 {
-#if 1
-    // From learnopengl.com
-    float weight[5] = float[] (0.227027, 0.1945946, 0.1216216, 0.054054, 0.016216);
+    float Pi = 6.28318530718; // 2*PI
 
-    vec2 tex_offset = 1.0 / textureSize(u_Texture, 0); // gets size of single texel
-    vec3 result = texture(u_Texture, v_TexCoord).rgb * weight[0]; // current fragment's contribution
-    if (u_Horizontal)
+    float Directions = 32.0;  // 模糊方向数
+    float Quality = 6.0;       // 每个方向上的采样质量（采样次数）
+    float Size = 16.0;         // 模糊半径
+
+    vec2 Radius = Size / textureSize(u_Texture, 0);
+
+    // 中心像素采样
+    vec3 centerColor = texture(u_Texture, v_TexCoord).rgb;
+    float centerLum = dot(centerColor, vec3(0.2126, 0.7152, 0.0722));
+
+    // 如果启用第一次处理且中心像素亮度低于阈值，则直接输出黑色（不进行模糊）
+    if (u_FirstPass && centerLum <= u_Threshold)
     {
-        for(int i = 1; i < 5; ++i)
+        o_Color = vec4(0.0, 0.0, 0.0, 1.0);
+        return;
+    }
+
+    vec3 result = centerColor;  // 先累加中心像素
+    float totalSamples = 1.0;   // 有效采样计数（中心像素已计入）
+
+    // 周围像素采样
+    for (float d = 0.0; d < Pi; d += Pi / Directions)
+    {
+        for (float i = 1.0 / Quality; i <= 1.0; i += 1.0 / Quality)
         {
-            result += texture(u_Texture, v_TexCoord + vec2(tex_offset.x * i, 0.0)).rgb * weight[i];
-            result += texture(u_Texture, v_TexCoord - vec2(tex_offset.x * i, 0.0)).rgb * weight[i];
-        }
-    }
-    else
-    {
-        for(int i = 1; i < 5; ++i)
-        {
-            result += texture(u_Texture, v_TexCoord + vec2(0.0, tex_offset.y * i)).rgb * weight[i];
-            result += texture(u_Texture, v_TexCoord - vec2(0.0, tex_offset.y * i)).rgb * weight[i];
+            vec2 offset = vec2(cos(d), sin(d)) * Radius * i;
+            vec3 sampleColor = texture(u_Texture, v_TexCoord + offset).rgb;
+
+            if (u_FirstPass)
+            {
+                float lum = dot(sampleColor, vec3(0.2126, 0.7152, 0.0722));
+                if (lum <= u_Threshold)
+                {
+                    // 低于阈值则贡献黑色，但采样点仍计入分母？这里选择不计入有效采样数
+                    // 若希望保持模糊能量，可以 continue 跳过累加，但需调整分母
+                    // 为简单起见，此处设为黑色并计入计数（分母不变），也可选择跳过
+                    sampleColor = vec3(0.0);
+                    // 如果希望忽略该采样点，可以 continue 并减少 totalSamples
+                    // 但为了效果平滑，这里保留为黑色并计入计数
+                }
+            }
+
+            result += sampleColor;
+            totalSamples += 1.0;
         }
     }
+
+    // 归一化：除以总采样数（包括中心像素）
+    // 若之前选择忽略低于阈值的采样点（continue），则需相应调整 totalSamples
+    result /= totalSamples;
+
     o_Color = vec4(result, 1.0);
-#else
-    // From https://www.shadertoy.com/view/Xltfzj
-
-    float Pi = 6.28318530718; // Pi*2
-
-    // GAUSSIAN BLUR SETTINGS {{{
-    float Directions =32.0; // BLUR DIRECTIONS (Default 16.0 - More is better but slower)
-    float Quality = 6.0; // BLUR QUALITY (Default 4.0 - More is better but slower)
-    float Size = 16.0; // BLUR SIZE (Radius)
-    // GAUSSIAN BLUR SETTINGS }}}
-
-    vec2 Radius = Size/textureSize(u_Texture, 0);
-
-    vec3 result = texture(u_Texture, v_TexCoord).rgb;
-    vec2 uv = v_TexCoord;
-    // Blur calculations
-    for( float d=0.0; d<Pi; d+=Pi/Directions)
-    {
-        for(float i=1.0/Quality; i<=1.0; i+=1.0/Quality)
-        {
-            result += texture( u_Texture, uv+vec2(cos(d),sin(d))*Radius*i).rgb;
-        }
-    }
-
-    // Output to screen
-    result /= Quality * Directions - 15.0;
-    o_Color = vec4(result, 1.0);
-#endif
 }