acd14f48b70c42fd539f85c277c09e06ac3a94e7
[libs/gl.git] / source / backends / opengl / vertexsetup_backend.cpp
1 #include <algorithm>
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 "vertexarray.h"
12 #include "vertexformat.h"
13 #include "vertexsetup.h"
14 #include "vertexsetup_backend.h"
15
16 using namespace std;
17
18 namespace Msp {
19 namespace GL {
20
21 OpenGLVertexSetup::OpenGLVertexSetup()
22 {
23         static Require req(ARB_vertex_array_object);
24         if(ARB_direct_state_access)
25                 glCreateVertexArrays(1, &id);
26         else
27                 glGenVertexArrays(1, &id);
28 }
29
30 OpenGLVertexSetup::OpenGLVertexSetup(OpenGLVertexSetup &&other):
31         id(other.id)
32 {
33         other.id = 0;
34 }
35
36 OpenGLVertexSetup::~OpenGLVertexSetup()
37 {
38         if(id)
39                 glDeleteVertexArrays(1, &id);
40 }
41
42 void OpenGLVertexSetup::require_format(const VertexFormat &fmt, bool instanced)
43 {
44         if(any_of(fmt.begin(), fmt.end(), is_integer_attribute))
45                 static Require _req(EXT_gpu_shader4);
46         if(instanced)
47                 static Require req(ARB_instanced_arrays);
48 }
49
50 void OpenGLVertexSetup::update(unsigned mask) const
51 {
52         static bool direct = ARB_direct_state_access && ARB_vertex_attrib_binding;
53
54         if(mask&VertexSetup::VERTEX_ARRAY)
55                 update_vertex_array(*static_cast<const VertexSetup *>(this)->vertex_array, 0, 0, direct);
56
57         if(mask&VertexSetup::INSTANCE_ARRAY)
58                 update_vertex_array(*static_cast<const VertexSetup *>(this)->inst_array, 1, 1, direct);
59
60         if(mask&VertexSetup::INDEX_BUFFER)
61         {
62                 unsigned buf_id = static_cast<const VertexSetup *>(this)->index_buffer->id;
63                 if(direct)
64                         glVertexArrayElementBuffer(id, buf_id);
65                 else
66                         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, buf_id);
67         }
68 }
69
70 void OpenGLVertexSetup::update_vertex_array(const VertexArray &array, unsigned binding, unsigned divisor, bool direct) const
71 {
72         if(!direct)
73         {
74                 OpenGLBuffer::unbind_scratch();
75                 glBindBuffer(GL_ARRAY_BUFFER, array.get_buffer()->id);
76         }
77
78         const VertexFormat &fmt = array.get_format();
79         unsigned stride = fmt.stride();
80         if(direct)
81         {
82                 glVertexArrayVertexBuffer(id, binding, array.get_buffer()->id, 0, stride);
83                 glVertexArrayBindingDivisor(id, binding, divisor);
84         }
85
86         unsigned offset = 0;
87         for(VertexAttribute a: fmt)
88         {
89                 unsigned sem = get_attribute_semantic(a);
90                 bool integer = is_integer_attribute(a);
91                 GLenum type = get_gl_type(get_attribute_source_type(a));
92                 unsigned cc = get_attribute_component_count(a);
93                 if(direct)
94                 {
95                         if(integer)
96                                 glVertexArrayAttribIFormat(id, sem, cc, type, offset);
97                         else
98                                 glVertexArrayAttribFormat(id, sem, cc, type, true, offset);
99                         glVertexArrayAttribBinding(id, sem, binding);
100                         glEnableVertexArrayAttrib(id, sem);
101                 }
102                 else
103                 {
104                         if(integer)
105                                 glVertexAttribIPointer(sem, cc, type, stride, reinterpret_cast<void *>(offset));
106                         else
107                                 glVertexAttribPointer(sem, cc, type, true, stride, reinterpret_cast<void *>(offset));
108                         if(ARB_instanced_arrays)
109                                 glVertexAttribDivisor(sem, divisor);
110                         glEnableVertexAttribArray(sem);
111                 }
112                 offset += get_attribute_size(a);
113         }
114
115         if(!direct)
116                 glBindBuffer(GL_ARRAY_BUFFER, 0);
117 }
118
119 void OpenGLVertexSetup::unload()
120 {
121         if(ARB_direct_state_access)
122         {
123                 glVertexArrayVertexBuffer(id, 0, 0, 0, 0);
124                 glVertexArrayVertexBuffer(id, 1, 0, 0, 0);
125                 glVertexArrayElementBuffer(id, 0);
126         }
127         else
128         {
129                 glBindVertexArray(id);
130                 glBindBuffer(GL_ARRAY_BUFFER, 0);
131
132                 for(VertexAttribute a: static_cast<const VertexSetup *>(this)->vertex_format)
133                 {
134                         unsigned sem = get_attribute_semantic(a);
135                         glDisableVertexAttribArray(sem);
136                         glVertexAttribPointer(sem, 1, GL_FLOAT, false, 0, 0);
137                 }
138                 for(VertexAttribute a: static_cast<const VertexSetup *>(this)->inst_format)
139                 {
140                         unsigned sem = get_attribute_semantic(a);
141                         glDisableVertexAttribArray(sem);
142                         glVertexAttribPointer(sem, 1, GL_FLOAT, false, 0, 0);
143                 }
144
145                 glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
146         }
147 }
148
149 void OpenGLVertexSetup::set_debug_name(const string &name)
150 {
151 #ifdef DEBUG
152         if(KHR_debug)
153                 glObjectLabel(GL_VERTEX_ARRAY, id, name.size(), name.c_str());
154 #else
155         (void)name;
156 #endif
157 }
158
159 } // namespace GL
160 } // namespace Msp