我一直试图按照OpenGL-3.3教程进行一段时间,但似乎我只能将纹理绑定到GL_TEXTURE0,否则我会得到一个黑色方块。
示例:
这有效
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
glActiveTexture(GL_TEXTURE0 + 0);
glBindTexture(GL_TEXTURE_2D, texture1);
glUniform1i(glGetUniformLocation(shader.program, "our_texture1"), 0);
shader.bind();
glBindVertexArray(vertex_array);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
glBindVertexArray(0);
这不是
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
glActiveTexture(GL_TEXTURE0 + 1);
glBindTexture(GL_TEXTURE_2D, texture1);
glUniform1i(glGetUniformLocation(shader.program, "our_texture1"), 1);
shader.bind();
glBindVertexArray(vertex_array);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
glBindVertexArray(0);
详细说明:
shader.bind
只需拨打glUseProgram
顶点着色器:
#version 330 core
layout (location = 0) in vec3 position;
layout (location = 1) in vec3 color;
layout (location = 2) in vec2 tex_coords;
out vec4 our_color;
out vec2 our_tex_coords;
void main()
{
gl_Position = vec4(position, 1.0f);
our_color = vec4(color, 1.0f);
our_tex_coords = tex_coords;
}
Fragment Shader:
#version 330 core
out vec4 color;
in vec4 our_color;
in vec2 our_tex_coords;
uniform sampler2D our_texture1;
void main()
{
color = texture(our_texture1, our_tex_coords);
}
纹理创建:
GLuint texture1;
glGenTextures(1, &texture1);
glBindTexture(GL_TEXTURE_2D, texture1);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
sf::Image image1;
if (!image1.loadFromFile("../Assets/container.jpg"))
{
error();
}
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, image1.getSize().x, image1.getSize().y, 0, GL_RGBA, GL_UNSIGNED_BYTE, image1.getPixelsPtr());
glGenerateMipmap(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, 0);
我可以检查文件是否正确加载。什么可能出错?
答案 0 :(得分:2)
早期的答案告诉您如何更改代码以使其工作,但给出了错误的解释。按顺序:
glActiveTexture(GL_TEXTURE0 + 1);
glBindTexture(GL_TEXTURE_2D, texture1);
glUniform1i(glGetUniformLocation(shader.program, "our_texture1"), 1);
shader.bind();
shader.bind()
调用glUseProgram()
时,序列确实存在问题。但它与glActiveTexture()
无关,glUniform1i()
与当前绑定的程序完全无关。
glUseProgram()
调用在当前绑定的程序上设置统一值。因此,关键是您在 glUniform*()
之前致电glActiveTexture(GL_TEXTURE0 + 1);
glBindTexture(GL_TEXTURE_2D, texture1);
shader.bind();
glUniform1i(glGetUniformLocation(shader.program, "our_texture1"), 1);
。例如,以下序列将起作用:
{{1}}
答案 1 :(得分:1)
您的代码看起来不错。 但我认为应该在glActiveTexture之前调用shader.bind()。
进一步提示:如果您希望在使用缩小时对纹理进行抗锯齿处理,请使用GL_LINEAR_MIPMAP_LINEAR而不是GL_LINEAR。这应该是开箱即用的,因为你已经生成了MIPMaps。
祝你好运, 克里斯