1) fix rgb interpolation and z-buffer

2) add function glClear

git-svn-id: svn://kolibrios.org@5159 a494cfbc-eb01-0410-851d-a64ba20cac60

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

@@ -51,6 +51,7 @@ if INTERP_Z eq 1
 	mov edx,[ecx+offs_zbup_y]
 	imul edx,[sx]
 	add edx,[ecx+offs_zbup_x]
+	shl edx,1
 	add edx,[eax+offs_zbuf_zbuf]
 	mov [pz],edx ;pz = zb.zbuf + (p1.y*sx + p1.x)
 	mov edx,[ecx+offs_zbup_z]
@@ -99,19 +100,34 @@ local .end_0
 	mov eax,[z]
 	shr eax, ZB_POINT_Z_FRAC_BITS
 	mov [zz],eax
-	cmp eax,[pz]
+	mov ebx,[pz]
+	cmp ax,word[ebx]
 	jl .end_0
 		RGBPIXEL
 		mov eax,dword[zz]
-		mov [pz],eax
+		mov ebx,[pz]
+		mov word[ebx],ax
 	.end_0:
-else ; INTERP_Z
+else
 	RGBPIXEL
-end if ; INTERP_Z
+end if
 }
 
 macro DRAWLINE d_x,d_y,inc_1,inc_2
 {
+local .mz_0
+local .mz_1
+local .mz_2
+local .mr_0
+local .mr_1
+local .mr_2
+local .mg_0
+local .mg_1
+local .mg_2
+local .mb_0
+local .mb_1
+local .mb_2
+
 	mov eax,d_x
 	mov [n],eax
 
@@ -119,32 +135,103 @@ macro DRAWLINE d_x,d_y,inc_1,inc_2
 	mov ecx,[p2]
 if INTERP_Z eq 1
 	mov eax,[ecx+offs_zbup_z]
+	cmp eax,[ebx+offs_zbup_z]
+	jg .mz_0
+	je .mz_1
+		;if(p2.z<p1.z)
+		sub eax,[ebx+offs_zbup_z]
+		neg eax
+		inc eax
+		xor edx,edx
+		div dword[n]
+		neg eax
+		inc eax
+		jmp .mz_2
+	.mz_0:
 	sub eax,[ebx+offs_zbup_z]
 	xor edx,edx
 	div dword[n]
+	jmp .mz_2
+	.mz_1:
+		xor eax,eax
+	.mz_2:
 	mov [zinc],eax ;zinc=(p2.z-p1.z)/n
 end if
 
 	;ebx=&p1, ecx=&p2
 	mov eax,[ecx+offs_zbup_r]
+	cmp eax,[ebx+offs_zbup_r]
+	jg .mr_0
+	je .mr_1
+		;if(p2.r<p1.r)
+		sub eax,[ebx+offs_zbup_r]
+		neg eax
+		inc eax
+		shl eax,8
+		xor edx,edx
+		div dword[n]
+		neg eax
+		inc eax
+		jmp .mr_2
+	.mr_0:
 	sub eax,[ebx+offs_zbup_r]
 	shl eax,8
 	xor edx,edx
 	div dword[n]
+	jmp .mr_2
+	.mr_1:
+		xor eax,eax
+	.mr_2:
 	mov [rinc],eax ;rinc=((p2.r-p1.r)<<8)/n
 
 	mov eax,[ecx+offs_zbup_g]
+	cmp eax,[ebx+offs_zbup_g]
+	jg .mg_0
+	je .mg_1
+		;if(p2.g<p1.g)
+		sub eax,[ebx+offs_zbup_g]
+		neg eax
+		inc eax
+		shl eax,8
+		xor edx,edx
+		div dword[n]
+		neg eax
+		inc eax
+		jmp .mg_2
+	.mg_0:
 	sub eax,[ebx+offs_zbup_g]
 	shl eax,8
 	xor edx,edx
 	div dword[n]
+	jmp .mg_2
+	.mg_1:
+		xor eax,eax
+	.mg_2:
 	mov [ginc],eax ;ginc=((p2.g-p1.g)<<8)/n
 
 	mov eax,[ecx+offs_zbup_b]
+	cmp eax,[ebx+offs_zbup_b]
+	jg .mb_0
+	je .mb_1
+		;if(p2.b<p1.b)
+		sub eax,[ebx+offs_zbup_b]
+		neg eax
+		inc eax
+		shl eax,8
+		xor edx,edx
+		div dword[n]
+		neg eax
+		inc eax
+		jmp .mb_2
+	.mb_0:
 	sub eax,[ebx+offs_zbup_b]
 	shl eax,8
 	xor edx,edx
 	div dword[n]
+	jmp .mb_2
+	.mb_1:
+		xor eax,eax
+	.mb_2:
 	mov [binc],eax ;binc=((p2.b-p1.b)<<8)/n
 
 	shl dword d_y,1
@@ -185,6 +272,7 @@ end if
 	add edi,[pp_inc_1]
 if INTERP_Z eq 1
 	mov eax,inc_1
+	shl eax,1
 	add [pz],eax
 end if
 	mov eax,d_x
@@ -195,6 +283,7 @@ end if
 	add edi,[pp_inc_2]
 if INTERP_Z eq 1
 	mov eax,inc_2
+	shl eax,1
 	add [pz],eax
 end if
 	mov eax,d_y