u_draw_quad.c revision d5062fb3a315c46d77d5c954a3e3c14be1907d33 
1/**************************************************************************
2 *
3 * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
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 TUNGSTEN GRAPHICS 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#include "pipe/p_context.h"
30#include "pipe/p_defines.h"
31#include "util/u_inlines.h"
32#include "util/u_draw_quad.h"
33#include "util/u_memory.h"
34#include "cso_cache/cso_context.h"
35
36
37/**
38 * Draw a simple vertex buffer / primitive.
39 * Limited to float[4] vertex attribs, tightly packed.
40 */
41void
42util_draw_vertex_buffer(struct pipe_context *pipe,
43                        struct cso_context *cso,
44                        struct pipe_resource *vbuf,
45                        uint offset,
46                        uint prim_type,
47                        uint num_verts,
48                        uint num_attribs)
49{
50   struct pipe_vertex_buffer vbuffer;
51
52   assert(num_attribs <= PIPE_MAX_ATTRIBS);
53
54   /* tell pipe about the vertex buffer */
55   memset(&vbuffer, 0, sizeof(vbuffer));
56   vbuffer.buffer = vbuf;
57   vbuffer.stride = num_attribs * 4 * sizeof(float);  /* vertex size */
58   vbuffer.buffer_offset = offset;
59   vbuffer.max_index = num_verts - 1;
60
61   if (cso) {
62      cso_set_vertex_buffers(cso, 1, &vbuffer);
63   } else {
64      pipe->set_vertex_buffers(pipe, 1, &vbuffer);
65   }
66
67   /* note: vertex elements already set by caller */
68
69   /* draw */
70   util_draw_arrays(pipe, prim_type, 0, num_verts);
71}
72
73
74
75/**
76 * Draw screen-aligned textured quad.
77 * Note: this isn't especially efficient.
78 */
79void
80util_draw_texquad(struct pipe_context *pipe, struct cso_context *cso,
81                  float x0, float y0, float x1, float y1, float z)
82{
83   uint numAttribs = 2, i, j;
84   uint vertexBytes = 4 * (4 * numAttribs * sizeof(float));
85   struct pipe_resource *vbuf = NULL;
86   uint *v = NULL;
87
88   v = MALLOC(vertexBytes);
89   if (v == NULL)
90      goto out;
91
92   /*
93    * Load vertex buffer
94    */
95   for (i = j = 0; i < 4; i++) {
96      v[j + 2] = z;   /* z */
97      v[j + 3] = 1.0; /* w */
98      v[j + 6] = 0.0; /* r */
99      v[j + 7] = 1.0; /* q */
100      j += 8;
101   }
102
103   v[0] = x0;
104   v[1] = y0;
105   v[4] = 0.0; /*s*/
106   v[5] = 0.0; /*t*/
107
108   v[8] = x1;
109   v[9] = y0;
110   v[12] = 1.0;
111   v[13] = 0.0;
112
113   v[16] = x1;
114   v[17] = y1;
115   v[20] = 1.0;
116   v[21] = 1.0;
117
118   v[24] = x0;
119   v[25] = y1;
120   v[28] = 0.0;
121   v[29] = 1.0;
122
123   vbuf = pipe_user_buffer_create(pipe->screen, v, vertexBytes,
124				  PIPE_BIND_VERTEX_BUFFER);
125   if (!vbuf)
126      goto out;
127
128   util_draw_vertex_buffer(pipe, cso, vbuf, 0, PIPE_PRIM_TRIANGLE_FAN, 4, 2);
129
130out:
131   if (vbuf)
132      pipe_resource_reference(&vbuf, NULL);
133
134   if (v)
135      FREE(v);
136}
137