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   for (i = 0 ; i < st->state.num_viewports; i++) {
58      scissor[i].minx = 0;
59      scissor[i].miny = 0;
60      scissor[i].maxx = fb_width;
61      scissor[i].maxy = fb_height;
62
63      if (ctx->Scissor.EnableFlags & (1 << i)) {
64         /* need to be careful here with xmax or ymax < 0 */
65         GLint xmax = MAX2(0, ctx->Scissor.ScissorArray[i].X + ctx->Scissor.ScissorArray[i].Width);
66         GLint ymax = MAX2(0, ctx->Scissor.ScissorArray[i].Y + ctx->Scissor.ScissorArray[i].Height);
67
68         if (ctx->Scissor.ScissorArray[i].X > (GLint)scissor[i].minx)
69            scissor[i].minx = ctx->Scissor.ScissorArray[i].X;
70         if (ctx->Scissor.ScissorArray[i].Y > (GLint)scissor[i].miny)
71            scissor[i].miny = ctx->Scissor.ScissorArray[i].Y;
72
73         if (xmax < (GLint) scissor[i].maxx)
74            scissor[i].maxx = xmax;
75         if (ymax < (GLint) scissor[i].maxy)
76            scissor[i].maxy = ymax;
77
78         /* check for null space */
79         if (scissor[i].minx >= scissor[i].maxx || scissor[i].miny >= scissor[i].maxy)
80            scissor[i].minx = scissor[i].miny = scissor[i].maxx = scissor[i].maxy = 0;
81      }
82
83      /* Now invert Y if needed.
84       * Gallium drivers use the convention Y=0=top for surfaces.
85       */
86      if (st->state.fb_orientation == Y_0_TOP) {
87         miny = fb->Height - scissor[i].maxy;
88         maxy = fb->Height - scissor[i].miny;
89         scissor[i].miny = miny;
90         scissor[i].maxy = maxy;
91      }
92
93      if (memcmp(&scissor[i], &st->state.scissor[i], sizeof(scissor[0])) != 0) {
94         /* state has changed */
95         st->state.scissor[i] = scissor[i];  /* struct copy */
96         changed = true;
97      }
98   }
99
100   if (changed) {
101      struct pipe_context *pipe = st->pipe;
102
103      pipe->set_scissor_states(pipe, 0, st->state.num_viewports, scissor);
104   }
105}
106
107void
108st_update_window_rectangles(struct st_context *st)
109{
110   struct pipe_scissor_state new_rects[PIPE_MAX_WINDOW_RECTANGLES];
111   const struct gl_context *ctx = st->ctx;
112   const struct gl_scissor_attrib *scissor = &ctx->Scissor;
113   unsigned i;
114   bool changed = false;
115   unsigned num_rects = scissor->NumWindowRects;
116   bool include = scissor->WindowRectMode == GL_INCLUSIVE_EXT;
117
118   if (ctx->DrawBuffer == ctx->WinSysDrawBuffer) {
119      num_rects = 0;
120      include = false;
121   }
122   for (i = 0; i < num_rects; i++) {
123      const struct gl_scissor_rect *rect = &scissor->WindowRects[i];
124      new_rects[i].minx = MAX2(rect->X, 0);
125      new_rects[i].miny = MAX2(rect->Y, 0);
126      new_rects[i].maxx = MAX2(rect->X + rect->Width, 0);
127      new_rects[i].maxy = MAX2(rect->Y + rect->Height, 0);
128   }
129   if (num_rects > 0 && memcmp(new_rects, st->state.window_rects.rects,
130                               num_rects * sizeof(struct pipe_scissor_state))) {
131      memcpy(st->state.window_rects.rects, new_rects,
132             num_rects * sizeof(struct pipe_scissor_state));
133      changed = true;
134   }
135   if (st->state.window_rects.num != num_rects) {
136      st->state.window_rects.num = num_rects;
137      changed = true;
138   }
139   if (st->state.window_rects.include != include) {
140      st->state.window_rects.include = include;
141      changed = true;
142   }
143   if (changed)
144      st->pipe->set_window_rectangles(
145            st->pipe, include, num_rects, new_rects);
146}
147