TinyGL:

- fixed setting of 'GL_FRONT_AND_BACK' mode
- fixed setting of 'GL_SPOT_DIRECTION' angle
- optimization of drawing triangles and lines
- fixes in 'gluCylinder' and 'gluSphere' functions
- 'gluDisk' function added
- optimize function 'calc_buf'
- clean code

Flag: add lighting

info3ds, info3ds_u, test_glu0, test_glu1, test_glu2,
textures0, textures1, textures2:
- updated programs using 'gluCylinder' and 'gluSphere'

programs/develop/libraries/TinyGL/asm_fork/ztriangle.inc

@@ -393,20 +393,9 @@ align 4
 		mov [dx1],eax ;dx1 = l2.x - l1.x
 		cmp edx,0 ;if (dy1 > 0) 
 		jle .els_3
-			xor edx,edx
-			cmp eax,0
-			jl .otr_dx1
 			shl eax,16
-			div dword[dy1] ;eax = (dx1 << 16) / dy1
-			jmp .end_3
-align 4
-			.otr_dx1:
-			neg eax
-			inc eax
-			shl eax,16
-			div dword[dy1] ;eax = (-dx1 << 16) / dy1
-			neg eax
-			inc eax
+			cdq
+			idiv dword[dy1] ;eax = (dx1 << 16) / dy1
 			jmp .end_3
 align 4
 		.els_3:
@@ -505,7 +494,6 @@ end if
 	.end_upd_l:
 
 	; compute values for the right edge
-
 	cmp dword[update_right],0 ;if(update_right)
 	je .end_upd_r
 		mov ebx,[pr1]
@@ -521,20 +509,9 @@ end if
 		mov [dy2],edx ;dy2 = pr2.y - pr1.y
 		cmp edx,0 ;if (dy2 > 0) 
 		jle .els_4
-			xor edx,edx
-			cmp eax,0
-			jl .otr_dx2
 			shl eax,16
-			div dword[dy2] ;eax = (dx2 << 16) / dy2
-			jmp .end_4
-align 4
-			.otr_dx2:
-			neg eax
-			inc eax ;dx2 *= -1
-			shl eax,16
-			div dword[dy2] ;eax = (-dx2 << 16) / dy2
-			neg eax
-			inc eax
+			cdq
+			idiv dword[dy2] ;eax = (dx2 << 16) / dy2
 			jmp .end_4
 align 4
 		.els_4: