diff --git a/README.md b/README.md
index 8816d3a..07124bb 100644
--- a/README.md
+++ b/README.md
@@ -65,4 +65,14 @@ entities:
     -> 10 (spinning platform)
         [.. hz_speed, vt_speed] with
             {hz_speed,vt_speed} = double
+
+    -> 11 (button trigger)
+        [.. freq, dtime] with
+            freq = int[0 - 15]
+            dtime = double[>0.0]
+
+    -> 12 (button block)
+        [.. freq, defaultState] with
+            freq = int[0 - 15]
+            defaultState = {0, 1}
 ```
\ No newline at end of file
diff --git a/bin/back b/bin/back
index 16eaa1a..4233d32 100755
Binary files a/bin/back and b/bin/back differ
diff --git a/levels/level_02/room_0 b/levels/level_02/room_0
index 9f84dd5..97c5631 100644
--- a/levels/level_02/room_0
+++ b/levels/level_02/room_0
@@ -4,8 +4,8 @@ Blocks :
 [-4.0, 20.0, 0.0, 2.0, 2.0, 2.0, 0.0, 0.0, 192, 192, 192]       // cp2
 
 Entities:
-[-2.0, 1.0 , -2.0, 2.0, 2.0, 2.0, 0.0, 0.0, 255, 255, 128, 1, 0, 8, 100, 1, 128, 128, 128]
-[-1.5, 1.5 , -1.5, 1.0, 1.0, 1.0, 0.0, 0.0, 192, 192, 192, 1, 0, 7, levels/level_01/, 7, great, 192, 192, 192]
+[8.0, 1.0 , 8.0, 2.0, 2.0, 2.0, 0.0, 0.0, 255, 255, 128, 1, 0, 8, 100, 1, 128, 128, 128]
+[8.5, 1.5 , 8.5, 1.0, 1.0, 1.0, 0.0, 0.0, 192, 192, 192, 1, 0, 7, levels/level_01/, 7, great, 192, 192, 192]
 
 [-3.5, 13.0, 0.5, 1.0, 1.0, 1.0, 0.0, 0.0, 255, 255, 128, 10, 0, 0]     // cp1 coin
 [-3.5, 23.0, 0.5, 1.0, 1.0, 1.0, 0.0, 0.0, 255, 255, 128, 10, 0, 0]     // cp2 coin
@@ -17,11 +17,11 @@ Entities:
 [-4.0, 8.0, -4.0, 2.0, 2.0, 2.0, 0.0, 0.0, 255, 255, 255, 1, 0, 9, 2.0, 2.0, 1]
 [-4.0, 10.0, -2.0, 2.0, 2.0, 2.0, 0.0, 0.0, 255, 255, 255, 1, 0, 9, 2.0, 2.0, 1]
 
-[-4.0, 11.0, 7.0, 2.0, 1.0, 2.0, 0.0, 0.0, 192, 192, 192, 1, 0, 5, 0.0, 0.0, 5.0, 0.0, 0.0, 5.0]   // section 2 (lines)
-[ 1.0, 11.0, 14.0, 2.0, 1.0, 2.0, 0.0, 0.0, 192, 192, 192, 1, 0, 5, 5.0, 0.0, 0.0, -5.0, 0.0, 0.0]
-[ 8.0, 16.0, 14.0, 2.0, 1.0, 2.0, 0.0, 0.0, 192, 192, 192, 1, 0, 5, 0.0, 5.0, 0.0, 0.0, 5.0, 4.0]
-[-4.0, 21.0, 7.0, 2.0, 1.0, 2.0, 0.0, 0.0, 192, 192, 192, 1, 0, 5, 0.0, 0.0, 5.0, 0.0, 0.0, -5.0]
-[ 1.0, 21.0, 14.0, 2.0, 1.0, 2.0, 0.0, 0.0, 192, 192, 192, 1, 0, 5, 5.0, 0.0, 0.0, 5.0, 0.0, 0.0]
+[-4.0, 11.0,  7.0, 2.0, 1.0, 2.0, 0.0, 0.0, 192, 192, 192, 1, 0, 5, 0.0, 0.0, 5.0,  0.0, 0.0,  5.0]
+[ 1.0, 11.0, 14.0, 2.0, 1.0, 2.0, 0.0, 0.0, 192, 192, 192, 1, 0, 5, 5.0, 0.0, 0.0, -5.0, 0.0,  0.0]
+[ 8.0, 16.0, 14.0, 2.0, 1.0, 2.0, 0.0, 0.0, 192, 192, 192, 1, 0, 5, 0.0, 5.0, 0.0,  0.0, 5.0,  0.0]
+[ 1.0, 21.0, 14.0, 2.0, 1.0, 2.0, 0.0, 0.0, 192, 192, 192, 1, 0, 5, 5.0, 0.0, 0.0,  5.0, 0.0,  0.0]
+[-4.0, 21.0,  7.0, 2.0, 1.0, 2.0, 0.0, 0.0, 192, 192, 192, 1, 0, 5, 0.0, 0.0, 5.0,  0.0, 0.0, -5.0]
 
 Weight :
 0
diff --git a/obj/base.o b/obj/base.o
index 7b2493b..393fa99 100644
Binary files a/obj/base.o and b/obj/base.o differ
diff --git a/obj/display.o b/obj/display.o
index c5d3acc..dbe4f8f 100644
Binary files a/obj/display.o and b/obj/display.o differ
diff --git a/obj/entities.o b/obj/entities.o
index b24182e..2c13995 100644
Binary files a/obj/entities.o and b/obj/entities.o differ
diff --git a/obj/generation.o b/obj/generation.o
index 9dd2193..eec1e29 100644
Binary files a/obj/generation.o and b/obj/generation.o differ
diff --git a/obj/main.o b/obj/main.o
index bbd16ce..29ad127 100644
Binary files a/obj/main.o and b/obj/main.o differ
diff --git a/obj/move.o b/obj/move.o
index 2726477..44cd232 100644
Binary files a/obj/move.o and b/obj/move.o differ
diff --git a/obj/proj.o b/obj/proj.o
index 29da31c..f20b1d6 100644
Binary files a/obj/proj.o and b/obj/proj.o differ
diff --git a/res/button_off.jpg b/res/button_off.jpg
new file mode 100644
index 0000000..7afe72d
Binary files /dev/null and b/res/button_off.jpg differ
diff --git a/res/button_on.png b/res/button_on.png
new file mode 100644
index 0000000..281aa53
Binary files /dev/null and b/res/button_on.png differ
diff --git a/src/base.c b/src/base.c
index 192298a..48ee0fa 100644
--- a/src/base.c
+++ b/src/base.c
@@ -98,6 +98,10 @@ double absf(double n) {
     }
 }
 
+bool xor(bool a, bool b) {
+    return ((a && !b) || (!a && b));
+}
+
 // n >= 0
 int reverse(int n) {
     int res = 0;
diff --git a/src/base.h b/src/base.h
index 298d043..aa64873 100644
--- a/src/base.h
+++ b/src/base.h
@@ -12,6 +12,7 @@ double maxd(double a, double b);
 float minf(float a, float b);
 float maxf(float a, float b);
 double absf(double n);
+bool xor(bool a, bool b);
 int reverse(int n);
 int convex_seg(int x1, int x2, double theta);
 double convex_tri(double a, double tha, double b, double thb, double c, double thc);
diff --git a/src/display.c b/src/display.c
index ce651c8..3171870 100644
--- a/src/display.c
+++ b/src/display.c
@@ -174,6 +174,14 @@ void gl_resetTexture() {
     glBindTexture(GL_TEXTURE_2D, textures[0]);
 }
 
+bool is_button_block_on(entity* ent) {
+    return (
+        (ent->entity_type != 11 && ent->entity_type != 12) ||
+        (ent->entity_type == 11 && buttonSwitch[ent->metai1]) ||
+        (ent->entity_type == 12 && xor(buttonSwitch[ent->metai1], ent->metai2))
+    );
+}
+
 void gl_renderAll(room* rtd, double offx, double offy, double offz) {
     //printf("------------------------\n");
     if(rtd != NULL) {
@@ -192,16 +200,12 @@ void gl_renderAll(room* rtd, double offx, double offy, double offz) {
         }
         for(int k = 0; k < rtd->ent_len; k++) {
             if(is_visible(rtd->ents[k]->pos, offx, offy, offz)) {
-                //printf("%d\n", rtd->ents[k]->tex);
-                //printf("r %d\n", rtd->ents[k]->entity_type); fflush(stdout);
-                if(rtd->ents[k]->entity_type != 9 || rtd->ents[k]->metai1) {
+                if(is_button_block_on(rtd->ents[k]) && (rtd->ents[k]->entity_type != 9 || rtd->ents[k]->metai1)) {
                     glBindTexture(GL_TEXTURE_2D, textures[rtd->ents[k]->tex]);
                 } else {
-                    //printf(">>%d<<\n", rtd->ents[k]->tex2);
                     glBindTexture(GL_TEXTURE_2D, textures[rtd->ents[k]->tex2]);
                 }
                 gl_renderCube(rtd->ents[k]->pos, offx, offy, offz);
-                //printf("OK\n"); fflush(stdout);
             }
         }
     }
diff --git a/src/entities.c b/src/entities.c
index 17a279b..28e96c7 100644
--- a/src/entities.c
+++ b/src/entities.c
@@ -114,20 +114,23 @@ void moving_xyz(double x, double y, double z, double w, double h, double d, doub
 // metai{3} = z_side (+/- 1)
 void moving_xyz_line(double x, double y, double z, double w, double h, double d, double hz_angle, double vt_angle, float dtime, entity* ent, cube_0* ret) {
     //printf("%lf %lf %lf", ent->metad7, ent->metad8, ent->metad9);
-    //printf("| %lf %lf %lf\n", ent->metad4, ent->metad5, ent->metad6);
+    //printf("| %lf %lf %lf\n\n", ent->metad4, ent->metad5, ent->metad6);
+    //printf("%lf %lf %lf -> (%lf %lf %lf)\n", x, y, z, (ent->metai1)*ent->metad4*dtime, (ent->metai2)*ent->metad5*dtime, (ent->metai3)*ent->metad6*dtime);
+    //printf("(%d %lf) (%d %lf) (%d %lf)\n\n", (ent->metai1), ent->metad4, (ent->metai2), ent->metad5, (ent->metai3), ent->metad6);
     ret->x += (ent->metai1)*ent->metad4*dtime;
     if(absf(ent->metad1 - ret->x) > ent->metad7) {
         //printf("-x-\n");
         ent->metai1 *= (-1);
         ret->x += (ent->metai1)*ent->metad4*dtime;
     }
+
     ret->y += (ent->metai2)*ent->metad5*dtime;
-    //printf("%lf, %lf | %lf\n", ent->metad2, ret->y, ent->metad8);
     if(absf(ent->metad2 - ret->y) > ent->metad8) {
         //printf("-y-\n");
         ent->metai2 *= (-1);
         ret->y += (ent->metai2)*ent->metad5*dtime;
     }
+
     ret->z += (ent->metai3)*ent->metad6*dtime;
     if(absf(ent->metad3 - ret->z) > ent->metad9) {
         //printf("-z-\n");
@@ -175,6 +178,16 @@ void spinning_translate(float dtime, int* hp, int* dmg, entity* ent, cube_0* ret
     
 }
 
+// metai1 = button freq                 (same for blocks)
+// matei2 = trigger state (0/1)         ('OFF state' for blocks)
+// metad1 = button activation time
+void update_button(float dtime, int* hp, int* dmg, entity* ent, cube_0* ret) {
+    if(!buttonSwitch[ent->metai1]) {
+        buttonSwitch[ent->metai1] = true;
+        buttonTimes[ent->metai1] = ent->metad1;
+    }
+}
+
 void detectHit(float dtime, int* hp, int* dmg, entity* ent, cube_0* ret) {
     if(ret->red == 193) {
         ret->red = 0;
diff --git a/src/entities.h b/src/entities.h
index 5863552..6c9cf3a 100644
--- a/src/entities.h
+++ b/src/entities.h
@@ -20,6 +20,7 @@ void subtitle_text_box(double x, double y, double z, double w, double h, double
 void beating_block(double x, double y, double z, double w, double h, double d, double hz_angle, double vt_angle, float dtime, entity* ent, cube_0* ret);
 void spinning_platform(double x, double y, double z, double w, double h, double d, double hz_angle, double vt_angle, float dtime, entity* ent, cube_0* ret);
 
+void update_button(float dtime, int* hp, int* dmg, entity* ent, cube_0* ret);
 void spinning_translate(float dtime, int* hp, int* dmg, entity* ent, cube_0* ret);
 void detectHit(float dtime, int* hp, int* dmg, entity* ent, cube_0* ret);
 void money(float dtime, int* hp, int* dmg, entity* ent, cube_0* ret);
diff --git a/src/generation.c b/src/generation.c
index a1c5379..29fa3d0 100644
--- a/src/generation.c
+++ b/src/generation.c
@@ -129,6 +129,22 @@ void init_ent_generator(int n) {
     hashtbl_entities[10].updatePos = &spinning_platform;
     hashtbl_entities[10].onHit = &spinning_translate;
     hashtbl_entities[10].onDeath = NULL;
+
+    hashtbl_entities[11].id = 11;
+    hashtbl_entities[11].tex = 10;
+    hashtbl_entities[11].tex2 = 11;
+    hashtbl_entities[11].name = "buttonInterface";
+    hashtbl_entities[11].updatePos = NULL;
+    hashtbl_entities[11].onHit = &update_button;
+    hashtbl_entities[11].onDeath = NULL;
+
+    hashtbl_entities[12].id = 12;
+    hashtbl_entities[12].tex = 8;
+    hashtbl_entities[12].tex2 = 9;
+    hashtbl_entities[12].name = "buttonBlock";
+    hashtbl_entities[12].updatePos = NULL;
+    hashtbl_entities[12].onHit = NULL;
+    hashtbl_entities[12].onDeath = NULL;
 }
 
 fct_entry* get_entry(int k0) {
@@ -519,6 +535,7 @@ void parse_one_room(int id, char* filename) {
             double speed_x = read_float(ptr);
             double speed_y = read_float(ptr);
             double speed_z = read_float(ptr);
+            printf("%lf %lf %lf %lf %lf %lf\n", amp_x, amp_y, amp_z, speed_x, speed_y, speed_z);
             pool[id].area->ents[k]->metad1 = cx;
             pool[id].area->ents[k]->metad2 = cy;
             pool[id].area->ents[k]->metad3 = cz;
@@ -603,7 +620,7 @@ void parse_one_room(int id, char* filename) {
             msg[ki] = 's'; ki += 1;
             msg[ki] = 's'; ki += 1;
             msg[ki] = '\0';
-            // k=18 if singlt digit
+            // k=18 if single digit
             
             //pool[id].area->ents[k]->metai1 = build_text_box(msg, ired, igreen, iblue);
             pool[id].area->ents[k]->metai2 = cost;
@@ -629,6 +646,30 @@ void parse_one_room(int id, char* filename) {
 
             pool[id].area->ents[k]->metad1 = hzspd;
             pool[id].area->ents[k]->metad2 = vtspd;
+        } else if(entry->id == 11) {
+            int freq = read_int(ptr);
+            double acttime = read_float(ptr);
+
+            if(freq < 0 || freq >= 16) {
+                fprintf(stderr, "WARNING : invalid frequency for button : %d\n", freq);
+                fprintf(stderr, "using frequency 0\n");
+                freq = 0;
+            }
+
+            pool[id].area->ents[k]->metai1 = freq;
+            pool[id].area->ents[k]->metad1 = acttime;
+        } else if(entry->id == 12) {
+            int freq = read_int(ptr);
+            int offstate = read_int(ptr);
+
+            if(freq < 0 || freq >= 16) {
+                fprintf(stderr, "WARNING : invalid frequency for button : %d\n", freq);
+                fprintf(stderr, "using frequency 0\n");
+                freq = 0;
+            }
+
+            pool[id].area->ents[k]->metai1 = freq;
+            pool[id].area->ents[k]->metai2 = offstate;
         } else {
             pool[id].area->ents[k]->metai3 = 0;
         }
diff --git a/src/main.c b/src/main.c
index e97ab67..34e9285 100644
--- a/src/main.c
+++ b/src/main.c
@@ -518,6 +518,8 @@ int main_alt() {
     //generate_texture_2D(9, "res/beat_off.png", JPG);
     generate_texture_2D(8, "res/sq_full.png", PNG);
     generate_texture_2D(9, "res/sq_dotted.png", PNG);
+    generate_texture_2D(10, "res/button_on.png", PNG);
+    generate_texture_2D(11, "res/button_off.jpg", JPG);
 
     printf("-----------------------------------------------------------------------------------------------\n"); fflush(stdout);
 
@@ -644,7 +646,8 @@ int main_alt() {
                 }
                 teleport_on_edge();
                 update_nearby_entities(delta, 1);
-                updateProj(delta); 
+                updateProj(delta);
+                update_buttons(delta);
             } else {
                 gl_drawRectAlpha(shaderProgramR, -1.0f, -1.0f, 2.0f, 2.0f, 0, 0, 0, 128);
                 gl_drawString(shaderProgramR, "game Paused", 0.0f,  0.1f, 0.08f, 128, 128, 255, 0.005f, 0);
diff --git a/src/move.c b/src/move.c
index d8fbed2..82d43a0 100644
--- a/src/move.c
+++ b/src/move.c
@@ -64,6 +64,9 @@ double sq2;
 float dmgCD;
 int lastDmg;
 
+bool buttonSwitch[16];
+float buttonTimes[16];
+
 void init_csts() {
     camx = 2.0;
     camy = 5.0;
@@ -86,6 +89,11 @@ void init_csts() {
     draw_type = 0;
     fade_dmg = 0;
 
+    for(int k = 0; k < 16; k++) {
+        buttonTimes[k] = 0.0f;
+        buttonSwitch[k] = false;
+    }
+
     dmgCD = 0.0f;
     lastDmg = player_hp;
 
@@ -94,6 +102,19 @@ void init_csts() {
     sq2 = sqrt(2);
 }
 
+void update_buttons(float dtime) {
+    for(int k = 0; k < 16; k++) {
+        if(buttonSwitch[k]) {
+            if(buttonTimes[k] <= dtime) {
+                buttonTimes[k] = 0.0f;
+                buttonSwitch[k] = false;
+            } else {
+                buttonTimes[k] -= dtime;
+            }
+        }
+    }
+}
+
 void set_player_coords(int old_chx, int old_chy) {
     for(int k = 0; k < current_room->tps_size; k++) {
         if(current_room->tps[k]->dest_chx == old_chx && current_room->tps[k]->dest_chy == old_chy) {
@@ -249,7 +270,10 @@ bool is_colliding(float dtime) {
 
                 for(int k = 0; k < vstd->ent_len; k++) {
                     //printf("%d -> %d\n", k, vstd->ents[k]->entity_type);
-                    if(vstd->ents[k]->entity_type != 9 || /* entityType == 9 */vstd->ents[k]->metai1) {
+                    if(    
+                        (vstd->ents[k]->entity_type != 12 || xor(buttonSwitch[vstd->ents[k]->metai1], vstd->ents[k]->metai2)) &&
+                        (vstd->ents[k]->entity_type != 9 || vstd->ents[k]->metai1)
+                    ) {
                         double dist = distance_pt_cube_0_3d_infinite(camx-2*room_width*w, camy, camz-2*room_depth*h, vstd->ents[k]->pos);
                         //printf("%lf vs %lf\n", dist, min_dist);
                         if(dist <= min_dist) {
@@ -348,6 +372,10 @@ void teleport_on_edge() {
             player_chx += 1;
             current_room = hashtbl_find_opt(visited, player_chx, player_chy);
             resetProj();
+            for(int k = 0; k < 16; k++) {
+                buttonSwitch[k] = false;
+                buttonTimes[k] = 0.0f;
+            }
         }
     } else if(camx <= -room_width) {
         if(!is_one_room) {
@@ -355,6 +383,10 @@ void teleport_on_edge() {
             player_chx -= 1;
             current_room = hashtbl_find_opt(visited, player_chx, player_chy);
             resetProj();
+            for(int k = 0; k < 16; k++) {
+                buttonSwitch[k] = false;
+                buttonTimes[k] = 0.0f;
+            }
         }
     } else if(camz >= room_depth) {
         if(!is_one_room) {
@@ -362,6 +394,10 @@ void teleport_on_edge() {
             player_chy += 1;
             current_room = hashtbl_find_opt(visited, player_chx, player_chy);
             resetProj();
+            for(int k = 0; k < 16; k++) {
+                buttonSwitch[k] = false;
+                buttonTimes[k] = 0.0f;
+            }
         }
     } else if(camz <= -room_depth) {
         if(!is_one_room) {
@@ -369,6 +405,10 @@ void teleport_on_edge() {
             player_chy -= 1;
             current_room = hashtbl_find_opt(visited, player_chx, player_chy);
             resetProj();
+            for(int k = 0; k < 16; k++) {
+                buttonSwitch[k] = false;
+                buttonTimes[k] = 0.0f;
+            }
         }
     }
 }
\ No newline at end of file
diff --git a/src/move.h b/src/move.h
index 82a5399..f17ae94 100644
--- a/src/move.h
+++ b/src/move.h
@@ -4,6 +4,8 @@
 void init_csts();
 bool is_colliding(float dtime);
 
+void update_buttons(float dtime);
+
 void teleport_on_edge();
 void movePlayerG(float dtime);
 
diff --git a/src/structure.h b/src/structure.h
index 2d1d553..2f6bb07 100644
--- a/src/structure.h
+++ b/src/structure.h
@@ -190,4 +190,7 @@ extern unsigned int textures[16];
 extern float dmgCD;
 extern int lastDmg;
 
+extern bool buttonSwitch[16];
+extern float buttonTimes[16];
+
 #endif
\ No newline at end of file
diff --git a/templates/room_0 b/templates/room_0
index 5d02da8..4c3c09a 100644
--- a/templates/room_0
+++ b/templates/room_0
@@ -14,6 +14,8 @@ Teleporters :
 
 Entities :
 [-1.0, 13.0, -1.0, 2.0, 2.0, 2.0, 0.0, 0.0, 255, 255, 255, 1, 0, 9, 1.5, 1.5, 0]
+[-1.0, 16.0, -1.0, 2.0, 1.0, 2.0, 0.0, 0.0, 128, 128, 128, 1, 0, 11, 4, 1.75]
+[-1.0, 19.0, -1.0, 2.0, 1.0, 2.0, 0.0, 0.0, 128, 128, 128, 1, 0, 12, 4, 1]
 
 Weight :
 50