1/**************************************************************************
2 *
3 * Copyright 2007 VMware, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28 /*
29  * Authors:
30  *   Keith Whitwell <keithw@vmware.com>
31  */
32
33
34#include "main/macros.h"
35#include "main/framebuffer.h"
36#include "st_context.h"
37#include "pipe/p_context.h"
38#include "st_atom.h"
39#include "st_util.h"
40
41
42/**
43 * Scissor depends on the scissor box, and the framebuffer dimensions.
44 */
45void
46st_update_scissor( struct st_context *st )
47{
48   struct pipe_scissor_state scissor[PIPE_MAX_VIEWPORTS];
49   const struct gl_context *ctx = st->ctx;
50   const struct gl_framebuffer *fb = ctx->DrawBuffer;
51   const unsigned int fb_width = _mesa_geometric_width(fb);
52   const unsigned int fb_height = _mesa_geometric_height(fb);
53   GLint miny, maxy;
54   unsigned i;
55   bool changed = false;
56
57   if (!ctx->Scissor.EnableFlags)
58      return;
59
60   for (i = 0 ; i < st->state.num_viewports; i++) {
61      scissor[i].minx = 0;
62      scissor[i].miny = 0;
63      scissor[i].maxx = fb_width;
64      scissor[i].maxy = fb_height;
65
66      if (ctx->Scissor.EnableFlags & (1 << i)) {
67         /* need to be careful here with xmax or ymax < 0 */
68         GLint xmax = MAX2(0, ctx->Scissor.ScissorArray[i].X + ctx->Scissor.ScissorArray[i].Width);
69         GLint ymax = MAX2(0, ctx->Scissor.ScissorArray[i].Y + ctx->Scissor.ScissorArray[i].Height);
70
71         if (ctx->Scissor.ScissorArray[i].X > (GLint)scissor[i].minx)
72            scissor[i].minx = ctx->Scissor.ScissorArray[i].X;
73         if (ctx->Scissor.ScissorArray[i].Y > (GLint)scissor[i].miny)
74            scissor[i].miny = ctx->Scissor.ScissorArray[i].Y;
75
76         if (xmax < (GLint) scissor[i].maxx)
77            scissor[i].maxx = xmax;
78         if (ymax < (GLint) scissor[i].maxy)
79            scissor[i].maxy = ymax;
80
81         /* check for null space */
82         if (scissor[i].minx >= scissor[i].maxx || scissor[i].miny >= scissor[i].maxy)
83            scissor[i].minx = scissor[i].miny = scissor[i].maxx = scissor[i].maxy = 0;
84      }
85
86      /* Now invert Y if needed.
87       * Gallium drivers use the convention Y=0=top for surfaces.
88       */
89      if (st->state.fb_orientation == Y_0_TOP) {
90         miny = fb->Height - scissor[i].maxy;
91         maxy = fb->Height - scissor[i].miny;
92         scissor[i].miny = miny;
93         scissor[i].maxy = maxy;
94      }
95
96      if (memcmp(&scissor[i], &st->state.scissor[i], sizeof(scissor[0])) != 0) {
97         /* state has changed */
98         st->state.scissor[i] = scissor[i];  /* struct copy */
99         changed = true;
100      }
101   }
102
103   if (changed) {
104      struct pipe_context *pipe = st->pipe;
105
106      pipe->set_scissor_states(pipe, 0, st->state.num_viewports, scissor);
107   }
108}
109
110void
111st_update_window_rectangles(struct st_context *st)
112{
113   struct pipe_scissor_state new_rects[PIPE_MAX_WINDOW_RECTANGLES];
114   const struct gl_context *ctx = st->ctx;
115   const struct gl_scissor_attrib *scissor = &ctx->Scissor;
116   unsigned i;
117   bool changed = false;
118   unsigned num_rects = scissor->NumWindowRects;
119   bool include = scissor->WindowRectMode == GL_INCLUSIVE_EXT;
120
121   if (ctx->DrawBuffer == ctx->WinSysDrawBuffer) {
122      num_rects = 0;
123      include = false;
124   }
125   for (i = 0; i < num_rects; i++) {
126      const struct gl_scissor_rect *rect = &scissor->WindowRects[i];
127      new_rects[i].minx = MAX2(rect->X, 0);
128      new_rects[i].miny = MAX2(rect->Y, 0);
129      new_rects[i].maxx = MAX2(rect->X + rect->Width, 0);
130      new_rects[i].maxy = MAX2(rect->Y + rect->Height, 0);
131   }
132   if (num_rects > 0 && memcmp(new_rects, st->state.window_rects.rects,
133                               num_rects * sizeof(struct pipe_scissor_state))) {
134      memcpy(st->state.window_rects.rects, new_rects,
135             num_rects * sizeof(struct pipe_scissor_state));
136      changed = true;
137   }
138   if (st->state.window_rects.num != num_rects) {
139      st->state.window_rects.num = num_rects;
140      changed = true;
141   }
142   if (st->state.window_rects.include != include) {
143      st->state.window_rects.include = include;
144      changed = true;
145   }
146   if (changed)
147      st->pipe->set_window_rectangles(
148            st->pipe, include, num_rects, new_rects);
149}
150