diff --git a/src/mame/drivers/taitoair.c b/src/mame/drivers/taitoair.c
index 0b6df18ffe6..0773dc2c1c6 100644
--- a/src/mame/drivers/taitoair.c
+++ b/src/mame/drivers/taitoair.c
@@ -477,11 +477,11 @@ static ADDRESS_MAP_START( DSP_map_data, AS_DATA, 16 )
 	AM_RANGE(0x3404, 0x3404) AM_WRITE(dsp_frustum_left_w)
 	AM_RANGE(0x3405, 0x3405) AM_WRITE(dsp_x_eyecoord_w)
 	AM_RANGE(0x3406, 0x3406) AM_WRITE(dsp_z_eyecoord_w)
-//  AM_RANGE(0x3407, 0x3407) AM_READ(?)
+	AM_RANGE(0x3407, 0x3407) AM_READ(dsp_x_return_r)
 	AM_RANGE(0x3408, 0x3408) AM_WRITE(dsp_frustum_bottom_w)
 	AM_RANGE(0x3409, 0x3409) AM_WRITE(dsp_y_eyecoord_w)
 	AM_RANGE(0x340a, 0x340a) AM_WRITE(dsp_rasterize_w)      /* Just a (lame) guess */
-//  AM_RANGE(0x340b, 0x340b) AM_READ(dsp_projection_y_r)
+	AM_RANGE(0x340b, 0x340b) AM_READ(dsp_y_return_r)
 //  AM_RANGE(0x3418, 0x341a) AM_WRITE(dsp_sqrt_w)
 //  AM_RANGE(0x341b, 0x341b) AM_WRITE(dsp_sqrt_r)
 //  AM_RANGE(0x341c, 0x341c) AM_READ(dsp_sqrt_flags1_r)
diff --git a/src/mame/includes/taitoair.h b/src/mame/includes/taitoair.h
index bc80ec503a0..2e40e7548f8 100644
--- a/src/mame/includes/taitoair.h
+++ b/src/mame/includes/taitoair.h
@@ -51,7 +51,7 @@ public:
     INT16 m_frustumBottom;
     INT16 m_eyecoordBuffer[4];  /* homogeneous */
 
-    bitmap_t *m_buffer3d;
+    //bitmap_t *m_buffer3d;
 };
 
 
@@ -67,3 +67,6 @@ WRITE16_HANDLER( dsp_z_eyecoord_w );
 WRITE16_HANDLER( dsp_rasterize_w );
 WRITE16_HANDLER( dsp_frustum_left_w );
 WRITE16_HANDLER( dsp_frustum_bottom_w );
+READ16_HANDLER( dsp_x_return_r );
+READ16_HANDLER( dsp_y_return_r );
+
diff --git a/src/mame/video/taitoair.c b/src/mame/video/taitoair.c
index c206d822a4e..09c0b6072da 100644
--- a/src/mame/video/taitoair.c
+++ b/src/mame/video/taitoair.c
@@ -518,6 +518,31 @@ WRITE16_HANDLER( dsp_rasterize_w )
 {
 	/* Does the pixel projection */
 	/* Presumably called when the eye coordinates are all loaded up in their x,y,z buffer */
+	#if 0
+	taitoair_state *state = space->machine().driver_data<taitoair_state>();
+
+	/* Construct a frustum from the system's most recently set left and bottom extents */
+	float m[16];
+	airInfernoFrustum(state->m_frustumLeft, state->m_frustumBottom, m);
+
+	int result[2];
+	projectEyeCoordToScreen(m,
+							32*16,	/* These are defined in the machine ctor */
+							28*16,  /* not sure how to get them here or if they're even correct */
+							state->m_eyecoordBuffer,
+							result);
+	#endif
+
+	/* Do not splat invalid results */
+	//if (result[0] == -1 && result[1] == -1)
+	//	return;
+
+	/* Splat a (any) non-translucent color */
+	//*BITMAP_ADDR16(state->m_buffer3d, result[1], result[0]) = 1;
+}
+
+READ16_HANDLER( dsp_x_return_r )
+{
 	taitoair_state *state = space->machine().driver_data<taitoair_state>();
 
 	/* Construct a frustum from the system's most recently set left and bottom extents */
@@ -531,15 +556,26 @@ WRITE16_HANDLER( dsp_rasterize_w )
 							state->m_eyecoordBuffer,
 							result);
 
-	/* Do not splat invalid results */
-	if (result[0] == -1 && result[1] == -1)
-		return;
-
-	/* Splat a (any) non-translucent color */
-	*BITMAP_ADDR16(state->m_buffer3d, result[1], result[0]) = 1;
+	return result[0];
 }
 
+READ16_HANDLER( dsp_y_return_r )
+{
+	taitoair_state *state = space->machine().driver_data<taitoair_state>();
 
+	/* Construct a frustum from the system's most recently set left and bottom extents */
+	float m[16];
+	airInfernoFrustum(state->m_frustumLeft, state->m_frustumBottom, m);
+
+	int result[2];
+	projectEyeCoordToScreen(m,
+							32*16,	/* These are defined in the machine ctor */
+							28*16,  /* not sure how to get them here or if they're even correct */
+							state->m_eyecoordBuffer,
+							result);
+
+	return result[1];
+}
 
 VIDEO_START( taitoair )
 {
@@ -550,7 +586,7 @@ VIDEO_START( taitoair )
 	height = machine.primary_screen->height();
 	state->m_framebuffer[0] = auto_bitmap_alloc(machine, width, height, BITMAP_FORMAT_INDEXED16);
 	state->m_framebuffer[1] = auto_bitmap_alloc(machine, width, height, BITMAP_FORMAT_INDEXED16);
-	state->m_buffer3d = auto_bitmap_alloc(machine, width, height, BITMAP_FORMAT_INDEXED16);
+	//state->m_buffer3d = auto_bitmap_alloc(machine, width, height, BITMAP_FORMAT_INDEXED16);
 }
 
 SCREEN_UPDATE( taitoair )
@@ -603,8 +639,8 @@ SCREEN_UPDATE( taitoair )
 	tc0080vco_tilemap_draw(state->m_tc0080vco, bitmap, cliprect, 2, 0, 0);
 
 	/* Hacky 3d bitmap */
-	copybitmap_trans(bitmap, state->m_buffer3d, 0, 0, 0, 0, cliprect, 0);
-	bitmap_fill(state->m_buffer3d, cliprect, 0);
+	//copybitmap_trans(bitmap, state->m_buffer3d, 0, 0, 0, 0, cliprect, 0);
+	//bitmap_fill(state->m_buffer3d, cliprect, 0);
 
 	return 0;
 }