让我们考虑一下这个MCVE:
from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.GLUT import *
import textwrap
from string import Template
def compile(shader_type, source):
identifier = glCreateShader(shader_type)
glShaderSource(identifier, source)
glCompileShader(identifier)
if not glGetShaderiv(identifier, GL_COMPILE_STATUS):
for i, l in enumerate(source.splitlines()):
print(f"{i+1}: {l}")
raise Exception(glGetShaderInfoLog(identifier).decode("utf-8"))
return identifier
def create_program(vs, fs):
vs_identifier = compile(GL_VERTEX_SHADER, vs)
fs_identifier = compile(GL_FRAGMENT_SHADER, fs)
program = glCreateProgram()
glAttachShader(program, vs_identifier)
glAttachShader(program, fs_identifier)
glLinkProgram(program)
if not glGetProgramiv(program, GL_LINK_STATUS):
raise RuntimeError(glGetProgramInfoLog(program))
return program
def set_uniform1f(prog, name, v0):
# print("set_uniform1f", name, glGetUniformLocation(prog, name))
glUniform1f(glGetUniformLocation(prog, name), v0)
def set_uniform1i(prog, name, v0):
# print("set_uniform1i", name, glGetUniformLocation(prog, name))
glUniform1i(glGetUniformLocation(prog, name), v0)
def set_uniform2f(prog, name, v0, v1):
# print("set_uniform2f", name, glGetUniformLocation(prog, name))
glUniform2f(glGetUniformLocation(prog, name), v0, v1)
class Window:
def __init__(self, w, h):
glutInit()
# glutInitContextVersion(3,2) # at least 3.2 is required, you can use a higer version when needed
# glutInitContextProfile(GLUT_CORE_PROFILE)
# glutInitContextFlags(GLUT_FORWARD_COMPATIBLE)
glutSetOption(GLUT_MULTISAMPLE, 16)
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH | GLUT_MULTISAMPLE)
glutInitWindowSize(w, h)
glutCreateWindow('Mcve uniforms')
glutReshapeFunc(self.reshape)
glutKeyboardFunc(self.keyboard_func)
glutKeyboardUpFunc(self.keyboard_up_func)
glutDisplayFunc(self.display)
glutIdleFunc(self.idle_func)
self.keys = {chr(i): False for i in range(256)}
# -------- Conflicting shader exposing bug --------
self.MAGIC_CONSTANT = 635
vs_code = textwrap.dedent("""\
void main()
{
gl_Position = ftransform();
}
""")
text = """\
#pragma optimize (off)
uniform vec2 resolution;
$block_declaration
vec3 f(vec2 x) {
x = sin(abs(x * 0.5));
float cs = cos(float($var_name) * 10037.5);
float ss = sin(float($var_name) * 12.5) * 0.09;
float t = sin(float($var_name)) * 0.5 + 0.5;
float d = sin(10. * length(x - vec2(cs, ss)) + mix(8., 10., t));
vec3 color = mix(vec3(0.8,0.86,0.85), vec3(0.52,0.72,0.79), sin(t) * 0.5);
return color*pow(d, 2.) / 5.;
}
void main() {
vec2 uv = (gl_FragCoord.xy / resolution.xy) * 2.0 - 1.0;
uv.x *= (resolution.x / resolution.y);
vec3 col = f(uv);
gl_FragColor = vec4(col*5.0, 1.0);
}
"""
VAR_NAME = "my_time"
fs_code0 = textwrap.dedent(Template(text).substitute(
block_declaration=f"int {VAR_NAME} = {self.MAGIC_CONSTANT};",
var_name=VAR_NAME
))
fs_code1 = textwrap.dedent(Template(text).substitute(
block_declaration=f"uniform int {VAR_NAME};",
var_name=VAR_NAME
))
print("SHADER0".center(80, '-'))
print(fs_code0)
print("SHADER1".center(80, '-'))
print(fs_code1)
# -------- Shader using time uniform --------
self.program0 = create_program(vs_code, fs_code0)
self.program1 = create_program(vs_code, fs_code1)
# -------- Setup --------
s = 1.0
glClearColor(1, 1, 1, 1)
glEnable(GL_DEPTH_TEST)
glMatrixMode(GL_PROJECTION)
glOrtho(-s, s, -s, s, -s, s)
glMatrixMode(GL_MODELVIEW)
glLoadIdentity()
def keyboard_func(self, *args):
self.keys[args[0].decode("utf8")] = True
def keyboard_up_func(self, *args):
self.keys[args[0].decode("utf8")] = False
def display(self):
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
if self.keys['w']:
# Case a) Using uniform
glUseProgram(self.program0)
set_uniform2f(self.program0, "resolution", self.width, self.height)
else:
# Case b) Using constant with same value than uniform
glUseProgram(self.program1)
set_uniform1i(self.program1, "my_time", self.MAGIC_CONSTANT)
set_uniform2f(self.program1, "resolution", self.width, self.height)
s = 0.5
glBegin(GL_QUADS)
glVertex3f(-s, -s, 0)
glVertex3f(s, -s, 0)
glVertex3f(s, s, 0)
glVertex3f(-s, s, 0)
glEnd()
glutSwapBuffers()
def run(self):
glutMainLoop()
def idle_func(self):
glutPostRedisplay()
def reshape(self, w, h):
glViewport(0, 0, w, h)
self.width = w
self.height = h
if __name__ == '__main__':
Window(800, 600).run()
运行后,您将看到生成了这两个片段着色器(您可以通过按“w”键在它们之间切换):
------------------------------------SHADER0-------------------------------------
#pragma optimize (off)
uniform vec2 resolution;
int my_time = 635;
vec3 f(vec2 x) {
x = sin(abs(x * 0.5));
float cs = cos(float(my_time) * 10037.5);
float ss = sin(float(my_time) * 12.5) * 0.09;
float t = sin(float(my_time)) * 0.5 + 0.5;
float d = sin(10. * length(x - vec2(cs, ss)) + mix(8., 10., t));
vec3 color = mix(vec3(0.8,0.86,0.85), vec3(0.52,0.72,0.79), sin(t) * 0.5);
return color*pow(d, 2.) / 5.;
}
void main() {
vec2 uv = (gl_FragCoord.xy / resolution.xy) * 2.0 - 1.0;
uv.x *= (resolution.x / resolution.y);
vec3 col = f(uv);
gl_FragColor = vec4(col*5.0, 1.0);
}
------------------------------------SHADER1-------------------------------------
#pragma optimize (off)
uniform vec2 resolution;
uniform int my_time;
vec3 f(vec2 x) {
x = sin(abs(x * 0.5));
float cs = cos(float(my_time) * 10037.5);
float ss = sin(float(my_time) * 12.5) * 0.09;
float t = sin(float(my_time)) * 0.5 + 0.5;
float d = sin(10. * length(x - vec2(cs, ss)) + mix(8., 10., t));
vec3 color = mix(vec3(0.8,0.86,0.85), vec3(0.52,0.72,0.79), sin(t) * 0.5);
return color*pow(d, 2.) / 5.;
}
void main() {
vec2 uv = (gl_FragCoord.xy / resolution.xy) * 2.0 - 1.0;
uv.x *= (resolution.x / resolution.y);
vec3 col = f(uv);
gl_FragColor = vec4(col*5.0, 1.0);
}
人们会期望两个着色器提供完全相同的输出。不幸的是,事实并非如此,如果您运行此代码,您将看到这两种代码看起来有多么不同:
问题
:
-
如果你能在那里复制它,你认为产生这些差异的原因是什么?这可能是司机的错误吗?
-
但最重要的是。。。即使这是一个驱动程序错误,我如何防止当前驱动程序的这种不当行为?
主要原因是我希望在着色器中使用统一变量作为硬编码值,而不会在调整着色器后得到任何不同的结果。
可以复制错误的规范
-
GeForce GTX 970M/PCIe/SSE2&4.4.0英伟达344.42和;win7终极版
-
GeForce GTX 1060 6GB/PCIe/SSE2&英伟达435.21&Debian 9.11
-
GeForce RTX 2070&driver 26.21.14.3160 2019年7月16日及;窗户
该漏洞不会出现的规格
-
Radeon Pro 560&苹果的烘焙驱动程序&马科斯·莫哈韦(10.14.4)
