Add support for integer vertex attributes
[libs/gl.git] / source / core / vertexsetup.cpp
1 #include <msp/core/raii.h>
2 #include <msp/gl/extensions/arb_direct_state_access.h>
3 #include <msp/gl/extensions/arb_instanced_arrays.h>
4 #include <msp/gl/extensions/arb_vertex_array_object.h>
5 #include <msp/gl/extensions/arb_vertex_attrib_binding.h>
6 #include <msp/gl/extensions/arb_vertex_buffer_object.h>
7 #include <msp/gl/extensions/arb_vertex_shader.h>
8 #include <msp/gl/extensions/ext_gpu_shader4.h>
9 #include <msp/gl/extensions/khr_debug.h>
10 #include "buffer.h"
11 #include "deviceinfo.h"
12 #include "error.h"
13 #include "gl.h"
14 #include "misc.h"
15 #include "vertexarray.h"
16 #include "vertexsetup.h"
17
18 using namespace std;
19
20 namespace Msp {
21 namespace GL {
22
23 VertexSetup::VertexSetup():
24         dirty(0),
25         vertex_array(0),
26         inst_array(0),
27         index_buffer(0),
28         index_type(UNSIGNED_SHORT)
29 {
30         static Require req(ARB_vertex_array_object);
31         if(ARB_direct_state_access)
32                 glCreateVertexArrays(1, &id);
33         else
34                 glGenVertexArrays(1, &id);
35 }
36
37 VertexSetup::~VertexSetup()
38 {
39         glDeleteVertexArrays(1, &id);
40 }
41
42 void VertexSetup::set_format(const VertexFormat &vfmt)
43 {
44         if(!verify_format(vfmt))
45                 throw invalid_argument("VertexSetup::set_format");
46         if(!vertex_format.empty())
47                 throw invalid_operation("VertexSetup::set_format");
48
49         require_format(vfmt);
50
51         vertex_format = vfmt;
52 }
53
54 void VertexSetup::set_format_instanced(const VertexFormat &vfmt, const VertexFormat &ifmt)
55 {
56         if(!verify_format(vfmt) || !verify_format(ifmt))
57                 throw invalid_argument("VertexSetup::set_format");
58         if(!vertex_format.empty())
59                 throw invalid_operation("VertexSetup::set_format");
60
61         require_format(vfmt);
62         require_format(ifmt);
63
64         vertex_format = vfmt;
65         inst_format = ifmt;
66 }
67
68 void VertexSetup::set_vertex_array(const VertexArray &a)
69 {
70         if(vertex_format.empty())
71                 throw invalid_operation("VertexSetup::set_vertex_array");
72         if(a.get_format()!=vertex_format)
73                 throw incompatible_data("VertexSetup::set_vertex_array");
74         if(!a.get_buffer())
75                 throw invalid_argument("VertexSetup::set_vertex_array");
76
77         vertex_array = &a;
78         dirty |= VERTEX_ARRAY;
79 }
80
81 void VertexSetup::set_instance_array(const VertexArray &a)
82 {
83         if(inst_format.empty())
84                 throw invalid_operation("VertexSetup::set_instance_array");
85         if(a.get_format()!=inst_format)
86                 throw incompatible_data("VertexSetup::set_instance_array");
87         if(!a.get_buffer())
88                 throw invalid_argument("VertexSetup::set_instance_array");
89
90         static Require req(ARB_instanced_arrays);
91
92         inst_array = &a;
93         dirty |= INSTANCE_ARRAY;
94 }
95
96 void VertexSetup::set_index_buffer(const Buffer &ibuf, DataType itype)
97 {
98         index_buffer = &ibuf;
99         index_type = itype;
100         dirty |= INDEX_BUFFER;
101 }
102
103 bool VertexSetup::verify_format(const VertexFormat &fmt)
104 {
105         if(fmt.empty())
106                 return false;
107
108         unsigned max_attribs = Limits::get_global().max_vertex_attributes;
109
110         for(const UInt16 *a=fmt.begin(); a!=fmt.end(); ++a)
111                 if(get_attribute_semantic(*a)>=max_attribs)
112                         return false;
113
114         return true;
115 }
116
117 void VertexSetup::require_format(const VertexFormat &fmt)
118 {
119         bool has_int = false;
120         for(const UInt16 *a=fmt.begin(); a!=fmt.end(); ++a)
121                 has_int = has_int | is_integer_attribute(*a);
122
123         if(has_int)
124                 static Require _req(EXT_gpu_shader4);
125 }
126
127 void VertexSetup::update() const
128 {
129         static bool direct = ARB_direct_state_access && ARB_vertex_attrib_binding;
130
131         if(dirty&VERTEX_ARRAY)
132                 update_vertex_array(*vertex_array, 0, 0, direct);
133
134         if(dirty&INSTANCE_ARRAY)
135                 update_vertex_array(*inst_array, 1, 1, direct);
136
137         if(dirty&INDEX_BUFFER)
138         {
139                 if(direct)
140                         glVertexArrayElementBuffer(id, index_buffer->get_id());
141                 else
142                         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, index_buffer->get_id());
143         }
144
145         dirty = 0;
146 }
147
148 void VertexSetup::update_vertex_array(const VertexArray &array, unsigned binding, unsigned divisor, bool direct) const
149 {
150         if(!direct)
151                 glBindBuffer(GL_ARRAY_BUFFER, array.get_buffer()->get_id());
152
153         const VertexFormat &fmt = array.get_format();
154         unsigned stride = fmt.stride();
155         if(direct)
156         {
157                 glVertexArrayVertexBuffer(id, binding, array.get_buffer()->get_id(), 0, stride);
158                 glVertexArrayBindingDivisor(id, binding, divisor);
159         }
160
161         unsigned offset = 0;
162         for(const UInt16 *a=fmt.begin(); a!=fmt.end(); ++a)
163         {
164                 unsigned sem = get_attribute_semantic(*a);
165                 bool integer = is_integer_attribute(*a);
166                 GLenum type = get_gl_type(get_attribute_source_type(*a));
167                 unsigned cc = get_attribute_component_count(*a);
168                 if(direct)
169                 {
170                         if(integer)
171                                 glVertexArrayAttribIFormat(id, sem, cc, type, offset);
172                         else
173                                 glVertexArrayAttribFormat(id, sem, cc, type, true, offset);
174                         glVertexArrayAttribBinding(id, sem, binding);
175                         glEnableVertexArrayAttrib(id, sem);
176                 }
177                 else
178                 {
179                         if(integer)
180                                 glVertexAttribIPointer(sem, cc, type, stride, reinterpret_cast<void *>(offset));
181                         else
182                                 glVertexAttribPointer(sem, cc, type, true, stride, reinterpret_cast<void *>(offset));
183                         if(ARB_instanced_arrays)
184                                 glVertexAttribDivisor(sem, divisor);
185                         glEnableVertexAttribArray(sem);
186                 }
187                 offset += get_attribute_size(*a);
188         }
189
190         if(!direct)
191                 glBindBuffer(GL_ARRAY_BUFFER, 0);
192 }
193
194 void VertexSetup::unload()
195 {
196         if(ARB_direct_state_access)
197         {
198                 glVertexArrayVertexBuffer(id, 0, 0, 0, 0);
199                 glVertexArrayVertexBuffer(id, 1, 0, 0, 0);
200                 glVertexArrayElementBuffer(id, 0);
201         }
202         else
203         {
204                 glBindVertexArray(id);
205                 glBindBuffer(GL_ARRAY_BUFFER, 0);
206
207                 for(const UInt16 *a=vertex_format.begin(); a!=vertex_format.end(); ++a)
208                 {
209                         unsigned sem = get_attribute_semantic(*a);
210                         glDisableVertexAttribArray(sem);
211                         glVertexAttribPointer(sem, 1, GL_FLOAT, false, 0, 0);
212                 }
213                 for(const UInt16 *a=inst_format.begin(); a!=inst_format.end(); ++a)
214                 {
215                         unsigned sem = get_attribute_semantic(*a);
216                         glDisableVertexAttribArray(sem);
217                         glVertexAttribPointer(sem, 1, GL_FLOAT, false, 0, 0);
218                 }
219
220                 glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
221         }
222
223         vertex_array = 0;
224         vertex_format = VertexFormat();
225         inst_array = 0;
226         inst_format = VertexFormat();
227         index_buffer = 0;
228 }
229
230 void VertexSetup::set_debug_name(const string &name)
231 {
232 #ifdef DEBUG
233         if(KHR_debug)
234                 glObjectLabel(GL_VERTEX_ARRAY, id, name.size(), name.c_str());
235 #else
236         (void)name;
237 #endif
238 }
239
240 } // namespace GL
241 } // namespace Msp