openGL MSAA在带有nouveau驱动程序的linux上不起作用
作者：互联网
最近我尝试在Linux下使用MSAA(多重采样抗锯齿).结果令人惊讶：一切都像Nvidia专有驱动程序的魅力一样,但是有了nouveau驱动程序它不起作用.关于这一点的奇怪之处在于glxingo说支持GLX_ARB_multisample并且我能够获得适当的FBConfig,GLX_SAMPLE_BUFFERS设置为1,GLX_SAMPLES设置为4(或8).但是在渲染时,图片没有应用抗锯齿.我的项目和freeglut都存在这个问题,所以我将提供一个基于过剩的小程序来证明这个问题：
/*
* Test multisampling and polygon smoothing.
*
* Brian Paul
* 4 November 2002
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <GL/glut.h>
static GLfloat Zrot = 0;
static GLboolean Anim = GL_TRUE;
static GLboolean HaveMultisample = GL_TRUE;
static GLboolean DoMultisample = GL_TRUE;
static void
PrintString(const char *s)
{
while (*s) {
glutBitmapCharacter(GLUT_BITMAP_8_BY_13, (int) *s);
s++;
}
}
static void
Polygon( GLint verts, GLfloat radius, GLfloat z )
{
int i;
for (i = 0; i < verts; i++) {
float a = (i * 2.0 * 3.14159) / verts;
float x = radius * cos(a);
float y = radius * sin(a);
glVertex3f(x, y, z);
}
}
static void
DrawObject( void )
{
glLineWidth(3.0);
glColor3f(1, 1, 1);
glBegin(GL_LINE_LOOP);
Polygon(12, 1.2, 0);
glEnd();
glLineWidth(1.0);
glColor3f(1, 1, 1);
glBegin(GL_LINE_LOOP);
Polygon(12, 1.1, 0);
glEnd();
glColor3f(1, 0, 0);
glBegin(GL_POLYGON);
Polygon(12, 0.4, 0.3);
glEnd();
glColor3f(0, 1, 0);
glBegin(GL_POLYGON);
Polygon(12, 0.6, 0.2);
glEnd();
glColor3f(0, 0, 1);
glBegin(GL_POLYGON);
Polygon(12, 0.8, 0.1);
glEnd();
glColor3f(1, 1, 1);
glBegin(GL_POLYGON);
Polygon(12, 1.0, 0);
glEnd();
}
static void
Display( void )
{
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
glColor3f(1, 1, 1);
if (HaveMultisample) {
glRasterPos2f(-3.1, -1.6);
if (DoMultisample)
PrintString("MULTISAMPLE");
else
PrintString("MULTISAMPLE (off)");
}
glRasterPos2f(-0.8, -1.6);
PrintString("No antialiasing");
glRasterPos2f(1.6, -1.6);
PrintString("GL_POLYGON_SMOOTH");
/* multisample */
if (HaveMultisample) {
glEnable(GL_DEPTH_TEST);
if (DoMultisample)
glEnable(GL_MULTISAMPLE_ARB);
glPushMatrix();
glTranslatef(-2.5, 0, 0);
glPushMatrix();
glRotatef(Zrot, 0, 0, 1);
DrawObject();
glPopMatrix();
glPopMatrix();
glDisable(GL_MULTISAMPLE_ARB);
glDisable(GL_DEPTH_TEST);
}
/* non-aa */
glEnable(GL_DEPTH_TEST);
glPushMatrix();
glTranslatef(0, 0, 0);
glPushMatrix();
glRotatef(Zrot, 0, 0, 1);
DrawObject();
glPopMatrix();
glPopMatrix();
glDisable(GL_DEPTH_TEST);
/* polygon smooth */
glEnable(GL_POLYGON_SMOOTH);
glEnable(GL_LINE_SMOOTH);
glEnable(GL_BLEND);
glPushMatrix();
glTranslatef(2.5, 0, 0);
glPushMatrix();
glRotatef(Zrot, 0, 0, 1);
DrawObject();
glPopMatrix();
glPopMatrix();
glDisable(GL_LINE_SMOOTH);
glDisable(GL_POLYGON_SMOOTH);
glDisable(GL_BLEND);
glutSwapBuffers();
}
static void
Reshape( int width, int height )
{
GLfloat ar = (float) width / (float) height;
glViewport( 0, 0, width, height );
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
glOrtho(-2.0*ar, 2.0*ar, -2.0, 2.0, -1.0, 1.0);
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
}
static void
Idle( void )
{
Zrot = 0.01 * glutGet(GLUT_ELAPSED_TIME);
glutPostRedisplay();
}
static void
Key( unsigned char key, int x, int y )
{
const GLfloat step = 1.0;
(void) x;
(void) y;
switch (key) {
case 'a':
Anim = !Anim;
if (Anim)
glutIdleFunc(Idle);
else
glutIdleFunc(NULL);
break;
case 'm':
DoMultisample = !DoMultisample;
break;
case 'z':
Zrot = (int) (Zrot - step);
break;
case 'Z':
Zrot = (int) (Zrot + step);
break;
case 27:
exit(0);
break;
}
glutPostRedisplay();
}
static void
Init( void )
{
/* GLUT imposes the four samples/pixel requirement */
int s;
glGetIntegerv(GL_SAMPLES_ARB, &s);
if (!glutExtensionSupported("GL_ARB_multisample") || s < 1) {
printf("Warning: multisample antialiasing not supported.\n");
HaveMultisample = GL_FALSE;
}
printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
printf("GL_SAMPLES_ARB = %d\n", s);
glBlendFunc(GL_SRC_ALPHA, GL_ONE);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glBlendFunc(GL_SRC_ALPHA_SATURATE, GL_ONE);
glGetIntegerv(GL_MULTISAMPLE_ARB, &s);
printf("GL_MULTISAMPLE_ARB = %d\n", s);
}
int
main( int argc, char *argv[] )
{
glutInit( &argc, argv );
glutInitWindowPosition( 0, 0 );
glutInitWindowSize( 600, 300 );
glutInitDisplayMode( GLUT_RGB | GLUT_ALPHA | GLUT_DOUBLE |
GLUT_DEPTH | GLUT_MULTISAMPLE );
glutCreateWindow(argv[0]);
glutReshapeFunc( Reshape );
glutKeyboardFunc( Key );
glutDisplayFunc( Display );
if (Anim)
glutIdleFunc( Idle );
Init();
glutMainLoop();
return 0;
}
这是glxinfo输出(不包括视觉信息)：
name of display: :0.0
display: :0 screen: 0
direct rendering: Yes
server glx vendor string: SGI
server glx version string: 1.4
server glx extensions:
GLX_ARB_multisample, GLX_EXT_import_context, GLX_EXT_texture_from_pixmap,
GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_MESA_copy_sub_buffer,
GLX_OML_swap_method, GLX_SGI_swap_control, GLX_SGIS_multisample,
GLX_SGIX_fbconfig, GLX_SGIX_pbuffer, GLX_SGIX_visual_select_group,
GLX_INTEL_swap_event
client glx vendor string: Mesa Project and SGI
client glx version string: 1.4
client glx extensions:
GLX_ARB_create_context, GLX_ARB_create_context_profile,
GLX_ARB_get_proc_address, GLX_ARB_multisample, GLX_EXT_import_context,
GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_EXT_framebuffer_sRGB,
GLX_EXT_create_context_es2_profile, GLX_MESA_copy_sub_buffer,
GLX_MESA_multithread_makecurrent, GLX_MESA_swap_control,
GLX_OML_swap_method, GLX_OML_sync_control, GLX_SGI_make_current_read,
GLX_SGI_swap_control, GLX_SGI_video_sync, GLX_SGIS_multisample,
GLX_SGIX_fbconfig, GLX_SGIX_pbuffer, GLX_SGIX_visual_select_group,
GLX_EXT_texture_from_pixmap, GLX_INTEL_swap_event
GLX version: 1.4
GLX extensions:
GLX_ARB_get_proc_address, GLX_ARB_multisample, GLX_EXT_import_context,
GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_MESA_copy_sub_buffer,
GLX_MESA_multithread_makecurrent, GLX_MESA_swap_control,
GLX_OML_swap_method, GLX_OML_sync_control, GLX_SGI_make_current_read,
GLX_SGI_swap_control, GLX_SGI_video_sync, GLX_SGIS_multisample,
GLX_SGIX_fbconfig, GLX_SGIX_pbuffer, GLX_SGIX_visual_select_group,
GLX_EXT_texture_from_pixmap
OpenGL vendor string: nouveau
OpenGL renderer string: Gallium 0.4 on NVC1
OpenGL version string: 2.1 Mesa 8.0.4
OpenGL shading language version string: 1.30
OpenGL extensions:
GL_ARB_multisample, GL_EXT_abgr, GL_EXT_bgra, GL_EXT_blend_color,
GL_EXT_blend_minmax, GL_EXT_blend_subtract, GL_EXT_copy_texture,
GL_EXT_polygon_offset, GL_EXT_subtexture, GL_EXT_texture_object,
GL_EXT_vertex_array, GL_EXT_compiled_vertex_array, GL_EXT_texture,
GL_EXT_texture3D, GL_IBM_rasterpos_clip, GL_ARB_point_parameters,
GL_EXT_draw_range_elements, GL_EXT_packed_pixels, GL_EXT_point_parameters,
GL_EXT_rescale_normal, GL_EXT_separate_specular_color,
GL_EXT_texture_edge_clamp, GL_SGIS_generate_mipmap,
GL_SGIS_texture_border_clamp, GL_SGIS_texture_edge_clamp,
GL_SGIS_texture_lod, GL_ARB_framebuffer_sRGB, GL_ARB_multitexture,
GL_EXT_framebuffer_sRGB, GL_IBM_multimode_draw_arrays,
GL_IBM_texture_mirrored_repeat, GL_ARB_texture_cube_map,
GL_ARB_texture_env_add, GL_ARB_transpose_matrix,
GL_EXT_blend_func_separate, GL_EXT_fog_coord, GL_EXT_multi_draw_arrays,
GL_EXT_secondary_color, GL_EXT_texture_env_add,
GL_EXT_texture_filter_anisotropic, GL_EXT_texture_lod_bias,
GL_INGR_blend_func_separate, GL_NV_blend_square, GL_NV_light_max_exponent,
GL_NV_texgen_reflection, GL_NV_texture_env_combine4,
GL_SUN_multi_draw_arrays, GL_ARB_texture_border_clamp,
GL_ARB_texture_compression, GL_EXT_framebuffer_object,
GL_EXT_texture_env_combine, GL_EXT_texture_env_dot3, GL_MESA_window_pos,
GL_NV_packed_depth_stencil, GL_NV_texture_rectangle, GL_ARB_depth_texture,
GL_ARB_occlusion_query, GL_ARB_shadow, GL_ARB_texture_env_combine,
GL_ARB_texture_env_crossbar, GL_ARB_texture_env_dot3,
GL_ARB_texture_mirrored_repeat, GL_ARB_window_pos,
GL_EXT_stencil_two_side, GL_EXT_texture_cube_map, GL_NV_depth_clamp,
GL_NV_fog_distance, GL_APPLE_packed_pixels, GL_APPLE_vertex_array_object,
GL_ARB_draw_buffers, GL_ARB_fragment_program, GL_ARB_fragment_shader,
GL_ARB_shader_objects, GL_ARB_vertex_program, GL_ARB_vertex_shader,
GL_ATI_draw_buffers, GL_ATI_texture_env_combine3, GL_EXT_shadow_funcs,
GL_EXT_stencil_wrap, GL_MESA_pack_invert, GL_NV_primitive_restart,
GL_ARB_depth_clamp, GL_ARB_fragment_program_shadow,
GL_ARB_half_float_pixel, GL_ARB_occlusion_query2, GL_ARB_point_sprite,
GL_ARB_shading_language_100, GL_ARB_sync, GL_ARB_texture_non_power_of_two,
GL_ARB_vertex_buffer_object, GL_ATI_blend_equation_separate,
GL_EXT_blend_equation_separate, GL_OES_read_format,
GL_ARB_color_buffer_float, GL_ARB_pixel_buffer_object,
GL_ARB_texture_compression_rgtc, GL_ARB_texture_rectangle,
GL_ATI_texture_compression_3dc, GL_EXT_packed_float,
GL_EXT_pixel_buffer_object, GL_EXT_texture_compression_rgtc,
GL_EXT_texture_mirror_clamp, GL_EXT_texture_rectangle,
GL_EXT_texture_sRGB, GL_EXT_texture_shared_exponent,
GL_ARB_framebuffer_object, GL_EXT_framebuffer_blit,
GL_EXT_framebuffer_multisample, GL_EXT_packed_depth_stencil,
GL_ARB_vertex_array_object, GL_ATI_separate_stencil,
GL_ATI_texture_mirror_once, GL_EXT_draw_buffers2, GL_EXT_draw_instanced,
GL_EXT_gpu_program_parameters, GL_EXT_texture_array,
GL_EXT_texture_compression_latc, GL_EXT_texture_integer,
GL_EXT_texture_sRGB_decode, GL_EXT_timer_query, GL_OES_EGL_image,
GL_MESA_texture_array, GL_ARB_copy_buffer, GL_ARB_depth_buffer_float,
GL_ARB_draw_instanced, GL_ARB_half_float_vertex, GL_ARB_instanced_arrays,
GL_ARB_map_buffer_range, GL_ARB_texture_rg, GL_ARB_texture_swizzle,
GL_ARB_vertex_array_bgra, GL_EXT_separate_shader_objects,
GL_EXT_texture_swizzle, GL_EXT_vertex_array_bgra,
GL_NV_conditional_render, GL_AMD_conservative_depth,
GL_AMD_draw_buffers_blend, GL_ARB_ES2_compatibility,
GL_ARB_draw_buffers_blend, GL_ARB_draw_elements_base_vertex,
GL_ARB_explicit_attrib_location, GL_ARB_fragment_coord_conventions,
GL_ARB_provoking_vertex, GL_ARB_sampler_objects, GL_ARB_seamless_cube_map,
GL_ARB_shader_texture_lod, GL_EXT_provoking_vertex, GL_EXT_texture_snorm,
GL_MESA_texture_signed_rgba, GL_NV_texture_barrier, GL_ARB_robustness,
GL_ARB_transform_feedback2, GL_ARB_conservative_depth,
GL_ARB_texture_storage, GL_EXT_transform_feedback
glewIsSupported表示扩展名可用,glGetIntegerv表示获取FBConfig时指定的样本数为4.
我不知道发生了什么.
编辑：这是glXQueryExtensionsString的输出：
GLX_ARB_get_proc_address GLX_ARB_multisample GLX_EXT_import_context GLX_EXT_visual_info GLX_EXT_visual_rating GLX_MESA_copy_sub_buffer GLX_MESA_multithread_makecurrent GLX_MESA_swap_control GLX_OML_swap_method GLX_OML_sync_control GLX_SGI_make_current_read GLX_SGI_swap_control GLX_SGI_video_sync GLX_SGIS_multisample GLX_SGIX_fbconfig GLX_SGIX_pbuffer GLX_SGIX_visual_select_group GLX_EXT_texture_from_pixmap
解决方法:
忘记关于MSAA.在nouveau,除非你有非常新的MESA内核X.org.
MSAA是OpenGL 3.0及更高版本的要求.直到最近,它在优先级列表上并不高.你需要Mesa 9.0.
(如果您需要有关如何获取所需软件的提示,请发布您的硬件和软件 – 发行版,内核,mesa,xorg – 版本).
标签：linux,opengl,antialiasing,mesa,msaa 来源： https://codeday.me/bug/20190709/1412722.html