Fork for library tinygl, assembly version.

Can draw lines, and do some matrix operations.

git-svn-id: svn://kolibrios.org@5153 a494cfbc-eb01-0410-851d-a64ba20cac60

programs/develop/libraries/TinyGL/asm_fork/kosgl.asm

@@ -0,0 +1,146 @@
+; simple gl like driver for TinyGL and KolibriOS - porting iadn
+
+
+struct TinyGLContext
+	gl_context dd ?
+	xsize dd ? ;+4
+	ysize dd ? ;+8
+	d_x dd ? ;+12
+	d_y dd ? ;+16
+	x dd ? ;+20
+	y dd ? ;+24
+ends
+
+;KOSGLContext kosglCreateContext(KOSGLContext shareList, int flags)
+;{
+;  TinyGLContext *ctx;
+;
+;  if (shareList != NULL) {
+;    gl_fatal_error("No sharing available in TinyGL");    
+;  }
+;
+;    ctx=gl_malloc(sizeof(TinyGLContext));
+;  if (!ctx)
+;      return NULL;
+;  ctx->gl_context=NULL;
+;  return (KOSGLContext) ctx;
+;}
+
+;void kosglDestroyContext( KOSGLContext ctx1 )
+;{
+;  TinyGLContext *ctx = (TinyGLContext *) ctx1;
+;  if (ctx->gl_context != NULL) {
+;    glClose();
+;  }
+;  gl_free(ctx);
+;}
+
+; resize the glx viewport : we try to use the xsize and ysize
+; given. We return the effective size which is guaranted to be smaller
+
+align 4
+proc gl_resize_viewport uses ebx ecx edx edi esi, context:dword, xsize_ptr:dword, ysize_ptr:dword
+	xor eax,eax
+
+	mov ecx,[xsize_ptr] ; ecx = &xsize
+	mov edi,[ecx]       ; edi =  xsize
+	mov esi,[ysize_ptr] ; esi = &ysize
+	mov esi,[esi]       ; esi =  ysize
+
+	; we ensure that xsize and ysize are multiples of 2 for the zbuffer.
+	; TODO: find a better solution
+	and edi, not 3
+	and esi, not 3
+
+	cmp edi,0
+	jne @f
+	cmp esi,0
+	jne @f
+		mov eax,-1
+		jmp .end_f
+	@@:
+
+	mov [ecx],edi
+	dec dword[ecx]
+	mov ecx,[ysize_ptr]
+	mov [ecx],esi
+	dec dword[ecx]
+
+	mov ebx,[context]
+	mov edx,[ebx+offs_cont_opaque] ; edx = (TinyGLContext *)context.opaque
+	mov [edx+4],edi
+	mov [edx+12],edi ;d_x = xsize
+	mov [edx+8],esi
+	mov [edx+16],esi ;d_y = ysize
+
+	; resize the Z buffer
+	stdcall ZB_resize, dword[ebx+offs_cont_zb],0,edi,esi
+	.end_f:
+	ret
+endp
+
+; we assume here that drawable is a window
+align 4
+proc kosglMakeCurrent uses ebx ecx, win_x0:dword, win_y0:dword, win_x:dword, win_y:dword, ctx1:dword
+	mov ebx,[ctx1]
+	cmp dword[ebx],0 ;if (ctx.gl_context == NULL)
+	jne .end_f
+		; create the TinyGL context
+		mov ecx,[win_x0]
+		mov [ebx+20],ecx ;ctx.x = win_x0
+		mov ecx,[win_y0]
+		mov [ebx+24],ecx ;ctx.y = win_y0
+		mov ecx,[win_x]
+		mov [ebx+12],ecx ;ctx.d_x = win_x
+		mov ecx,[win_y]
+		mov [ebx+16],ecx ;ctx.d_y = win_y
+
+		; currently, we only support 16 bit rendering
+		xor eax,eax
+		stdcall ZB_open, dword[win_x], dword[win_y], dword ZB_MODE_RGB24, eax,eax,eax,eax ;NULL,NULL,NULL
+
+		cmp eax,0
+		jne @f
+			stdcall dbg_print,f_kosgl_1,err_0
+			xor eax,eax
+			jmp .err_f
+		@@:
+
+		; initialisation of the TinyGL interpreter
+		stdcall glInit, eax
+
+		call gl_get_context
+		mov [ebx],eax ;ctx.gl_context = eax
+
+		mov [eax+offs_cont_opaque],ebx ;ctx.gl_context.opaque = ctx
+		mov dword[eax+offs_cont_gl_resize_viewport],gl_resize_viewport
+
+		; set the viewport : we force a call to gl_resize_viewport
+		dec dword[eax+offs_cont_viewport+offs_vpor_xsize]
+		dec dword[eax+offs_cont_viewport+offs_vpor_ysize]
+
+		stdcall glViewport, 0, 0, [win_x], [win_y]
+	.end_f:
+	xor eax,eax
+	inc eax
+	.err_f:
+	ret
+endp
+
+align 4
+proc kosglSwapBuffers uses eax ebx ecx edx esi
+	; retrieve the current TinyGLContext
+	call gl_get_context
+	mov ebx,[eax+offs_cont_zb]
+	mov ebx,[ebx+offs_zbuf_pbuf]
+	mov esi,[eax+offs_cont_opaque] ;esi = &context.opaque
+	mov eax,7
+	mov ecx,[esi+12] ;d_x
+	shl ecx,16
+	mov cx,[esi+16] ;d_y
+	mov edx,[esi+20] ;x
+	shl edx,16
+	mov dx,[esi+24] ;y
+	int 0x40
+	ret
+endp