我正在尝试将计算着色器应用于纹理以更新其值。我知道简单地说有些东西不起作用不是一个很好的问题,但我确实花了很多时间试图得到这份工作。
着色器程序编译得很好。将glMemoryBarrier(GL_SHADER_IMAGE_ACCESS_BARRIER_BIT);
行更改为glMemoryBarrier(GL_ALL_BARRIER_BITS); glFinish();
没有影响。
以下是显示该问题的最小程序。SDL仅用于为GL上下文创建不可见窗口。程序期望用e1d2d1填充纹理并打印它们,但只打印e1d3d1。
# define SDL_MAIN_HANDLED
# include <stdio.h>
# include <assert.h>
# include <GL/glew.h>
# include <SDL2/SDL.h>
# define WIDTH 512
# define HEIGHT WIDTH
static const char *SHADER =
"#version 430n" // "#version 310 esn"
"layout (local_size_x = 1, local_size_y = 1) in;n"
"layout (rgba32f, binding = 0) uniform image2D image;n"
"void main() {n"
"imageStore(image, ivec2(gl_GlobalInvocationID.xy), vec4(0.5f));n"
"}n";
int main() {
SDL_SetMainReady();
assert(!SDL_Init(SDL_INIT_VIDEO));
SDL_Window *window = SDL_CreateWindow("", SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED, 0, 0, SDL_WINDOW_HIDDEN | SDL_WINDOW_OPENGL);
assert(window);
SDL_GLContext gl = SDL_GL_CreateContext(window);
assert(gl);
assert(glewInit() == GLEW_OK);
GLuint tex;
glGenTextures(1, &tex);
glBindTexture(GL_TEXTURE_2D, tex);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA32F, WIDTH, HEIGHT, 0, GL_RGBA,
GL_FLOAT, 0);
glBindImageTexture(0, tex, 0, 0, 0, GL_READ_WRITE, GL_RGBA32F);
GLuint shader = glCreateShader(GL_COMPUTE_SHADER);
glShaderSource(shader, 1, &SHADER, 0);
glCompileShader(shader);
GLuint program = glCreateProgram();
glAttachShader(program, shader);
glLinkProgram(program);
glUseProgram(program);
glDispatchCompute(WIDTH, HEIGHT, 1);
glMemoryBarrier(GL_ALL_BARRIER_BITS);
glFinish();
static float a[WIDTH * HEIGHT * 4];
glGetTexImage(GL_TEXTURE_2D, 0, GL_RGBA, GL_FLOAT, a);
puts((const char *)glGetString(GL_VERSION));
for (int i = 0; i < 16; ++i) printf("%fn", a[i]);
return 0;
}
1条答案
按热度按时间gcxthw6b1#
如果不生成mipmap(使用
glGenerateMipmap
),则必须更改GL_TEXTURE_MIN_FILTER
。由于默认过滤器为GL_NEAREST_MIPMAP_LINEAR
,因此如果不将最小化函数更改为GL_NEAREST
或GL_LINEAR
,则纹理将是“Mipmap Complete”。