diff --git a/src/standalone_srgb_antialiasing_experiments.c b/src/standalone_srgb_antialiasing_experiments.c
index 7e3d8af..6cd7b0a 100644
--- a/src/standalone_srgb_antialiasing_experiments.c
+++ b/src/standalone_srgb_antialiasing_experiments.c
@@ -42,6 +42,7 @@ typedef double F64;
 #define U64FromPtr(ptr) (U64)(ptr)
 #define PtrFromU64(ptr) (void*)(x)
 
+#define ArrayCount(a) ((sizeof(a))/(sizeof(*a)))
 #define Member(T,m) ((T*)0)->m
 #define PtrOffsetOf(T,m) (void*)(&Member(T,m))
 #define OffsetOf(T,m) U64FromPtr(&Member(T,m))
@@ -105,9 +106,13 @@ typedef unsigned char GLboolean;
 
 #define GL_COLOR_BUFFER_BIT 0x00004000
 
-
 #define GL_TRIANGLES       0x0004
 
+#define GL_SRC_ALPHA           0x0302
+#define GL_ONE_MINUS_SRC_ALPHA 0x0303
+
+#define GL_BLEND           0x0BE2
+
 #define GL_TEXTURE_2D      0x0DE1
 
 #define GL_UNSIGNED_BYTE   0x1401
@@ -449,6 +454,12 @@ opengl_render_init(void){
                          canvas_texture, 0);
   }
   
+  //- enable alpha blend
+  {
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+    glEnable(GL_BLEND);
+  }
+  
   //- test3 texture
   {
     U8 test3_img[16*3] = {0};
@@ -539,6 +550,17 @@ opengl_draw_texture_geometry(Vertex *v, U64 count, U32 texture){
 ////////////////////////////////
 //- Main
 
+typedef struct Rect{
+  F32 x0;
+  F32 y0;
+  F32 x1;
+  F32 y1;
+  F32 r;
+  F32 g;
+  F32 b;
+  F32 a;
+} Rect;
+
 int
 WinMain(HINSTANCE hInstance,
         HINSTANCE hPrevInstance,
@@ -579,6 +601,7 @@ WinMain(HINSTANCE hInstance,
     F32 test2_y = graphics_h - 60.f;
     F32 test3_y = graphics_h - 110.f;
     F32 test4_y = graphics_h - 160.f;
+    F32 test5_y = graphics_h - 340.f;
     
     // render to canvas frame buffer
     {
@@ -779,6 +802,74 @@ WinMain(HINSTANCE hInstance,
           }
         }
         
+        // 5: transparency blending
+        {
+          Rect rect[20] = {0};
+          U32 recti = 0;
+          
+          F32 top_y = test5_y;
+          F32 bot_y = top_y - 100.f;
+          
+          rect[recti].x0 = grad_x0;
+          rect[recti].y0 = bot_y;
+          rect[recti].x1 = grad_x1;
+          rect[recti].y1 = top_y;
+          rect[recti].r = 1.f;
+          rect[recti].g = 1.f;
+          rect[recti].b = 1.f;
+          rect[recti].a = 1.f;
+          recti += 1;
+          
+          for (U32 i = 0; i < 3; i += 1){
+            rect[recti].x0 = grad_x0;
+            rect[recti].y0 = top_y - 10.f - 30.f*i;
+            rect[recti].x1 = grad_x1;
+            rect[recti].y1 = top_y - 30.f - 30.f*i;
+            rect[recti].r = (i == 0)?1.f:0.f;
+            rect[recti].g = (i == 1)?1.f:0.f;
+            rect[recti].b = (i == 2)?1.f:0.f;
+            rect[recti].a = 1.f;
+            recti += 1;
+          }
+          
+          for (U32 j = 0; j < 2; j += 1){
+            for (U32 i = 0; i < 3; i += 1){
+              rect[recti].x0 = grad_x0 + 10.f + 30.f*i + 100.f*j;
+              rect[recti].y0 = bot_y;
+              rect[recti].x1 = grad_x0 + 30.f + 30.f*i + 100.f*j;
+              rect[recti].y1 = top_y;
+              rect[recti].r = (i == 0)?1.f:0.f;
+              rect[recti].g = (i == 1)?1.f:0.f;
+              rect[recti].b = (i == 2)?1.f:0.f;
+              rect[recti].a = (j == 0)?0.5f:0.75f;
+              recti += 1;
+            }
+          }
+          
+          for (U32 j = 0; j < recti; j += 1){
+            Vertex v[6] = {0};
+            v[0].px = rect[j].x0; v[0].py = rect[j].y0;
+            v[1].px = rect[j].x0; v[1].py = rect[j].y1;
+            v[2].px = rect[j].x1; v[2].py = rect[j].y0;
+            v[3].px = rect[j].x0; v[3].py = rect[j].y1;
+            v[4].px = rect[j].x1; v[4].py = rect[j].y0;
+            v[5].px = rect[j].x1; v[5].py = rect[j].y1;
+            for (U32 k = 0; k < 6; k += 1){
+              v[k].cr = rect[j].r;
+              v[k].cg = rect[j].g;
+              v[k].cb = rect[j].b;
+              v[k].ca = rect[j].a;
+            }
+            
+            if (test_idx == 0){
+              opengl_draw_basic_geometry(v, 6);
+            }
+            else{
+              opengl_draw_srgb_in_geometry(v, 6);
+            }
+          }
+          
+        }
       }
       
     }