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27#include "qemu/osdep.h"
28#include "ui/shader.h"
29
30#include "ui/shader/texture-blit-vert.h"
31#include "ui/shader/texture-blit-flip-vert.h"
32#include "ui/shader/texture-blit-frag.h"
33
34struct QemuGLShader {
35 GLint texture_blit_prog;
36 GLint texture_blit_flip_prog;
37 GLint texture_blit_vao;
38};
39
40
41
42static GLuint qemu_gl_init_texture_blit(GLint texture_blit_prog)
43{
44 static const GLfloat in_position[] = {
45 -1, -1,
46 1, -1,
47 -1, 1,
48 1, 1,
49 };
50 GLint l_position;
51 GLuint vao, buffer;
52
53 glGenVertexArrays(1, &vao);
54 glBindVertexArray(vao);
55
56
57 glGenBuffers(1, &buffer);
58 glBindBuffer(GL_ARRAY_BUFFER, buffer);
59 glBufferData(GL_ARRAY_BUFFER, sizeof(in_position), in_position,
60 GL_STATIC_DRAW);
61
62 l_position = glGetAttribLocation(texture_blit_prog, "in_position");
63 glVertexAttribPointer(l_position, 2, GL_FLOAT, GL_FALSE, 0, 0);
64 glEnableVertexAttribArray(l_position);
65
66 glBindBuffer(GL_ARRAY_BUFFER, 0);
67 glBindVertexArray(0);
68
69 return vao;
70}
71
72void qemu_gl_run_texture_blit(QemuGLShader *gls, bool flip)
73{
74 glUseProgram(flip
75 ? gls->texture_blit_flip_prog
76 : gls->texture_blit_prog);
77 glBindVertexArray(gls->texture_blit_vao);
78 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
79}
80
81
82
83static GLuint qemu_gl_create_compile_shader(GLenum type, const GLchar *src)
84{
85 GLuint shader;
86 GLint status, length;
87 char *errmsg;
88
89 shader = glCreateShader(type);
90 glShaderSource(shader, 1, &src, 0);
91 glCompileShader(shader);
92
93 glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
94 if (!status) {
95 glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &length);
96 errmsg = g_malloc(length);
97 glGetShaderInfoLog(shader, length, &length, errmsg);
98 fprintf(stderr, "%s: compile %s error\n%s\n", __func__,
99 (type == GL_VERTEX_SHADER) ? "vertex" : "fragment",
100 errmsg);
101 g_free(errmsg);
102 return 0;
103 }
104 return shader;
105}
106
107static GLuint qemu_gl_create_link_program(GLuint vert, GLuint frag)
108{
109 GLuint program;
110 GLint status, length;
111 char *errmsg;
112
113 program = glCreateProgram();
114 glAttachShader(program, vert);
115 glAttachShader(program, frag);
116 glLinkProgram(program);
117
118 glGetProgramiv(program, GL_LINK_STATUS, &status);
119 if (!status) {
120 glGetProgramiv(program, GL_INFO_LOG_LENGTH, &length);
121 errmsg = g_malloc(length);
122 glGetProgramInfoLog(program, length, &length, errmsg);
123 fprintf(stderr, "%s: link program: %s\n", __func__, errmsg);
124 g_free(errmsg);
125 return 0;
126 }
127 return program;
128}
129
130static GLuint qemu_gl_create_compile_link_program(const GLchar *vert_src,
131 const GLchar *frag_src)
132{
133 GLuint vert_shader, frag_shader, program = 0;
134
135 vert_shader = qemu_gl_create_compile_shader(GL_VERTEX_SHADER, vert_src);
136 frag_shader = qemu_gl_create_compile_shader(GL_FRAGMENT_SHADER, frag_src);
137 if (!vert_shader || !frag_shader) {
138 goto end;
139 }
140
141 program = qemu_gl_create_link_program(vert_shader, frag_shader);
142
143end:
144 glDeleteShader(vert_shader);
145 glDeleteShader(frag_shader);
146
147 return program;
148}
149
150
151
152QemuGLShader *qemu_gl_init_shader(void)
153{
154 QemuGLShader *gls = g_new0(QemuGLShader, 1);
155
156 gls->texture_blit_prog = qemu_gl_create_compile_link_program
157 (texture_blit_vert_src, texture_blit_frag_src);
158 gls->texture_blit_flip_prog = qemu_gl_create_compile_link_program
159 (texture_blit_flip_vert_src, texture_blit_frag_src);
160 if (!gls->texture_blit_prog || !gls->texture_blit_flip_prog) {
161 exit(1);
162 }
163
164 gls->texture_blit_vao =
165 qemu_gl_init_texture_blit(gls->texture_blit_prog);
166
167 return gls;
168}
169
170void qemu_gl_fini_shader(QemuGLShader *gls)
171{
172 if (!gls) {
173 return;
174 }
175 glDeleteProgram(gls->texture_blit_prog);
176 glDeleteProgram(gls->texture_blit_flip_prog);
177 glDeleteProgram(gls->texture_blit_vao);
178 g_free(gls);
179}
180