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我使用Assimp渲染三維模型的OpenGL ES 2.0。我目前有一個奇怪的問題，其中模型的某些部分不可見，即使它們應該是。人們很容易看到它在這些圖片：的OpenGL ES 2.0：模型的部分，其中它們不應該遮擋。是z緩衝區的責任？
在我這個渲染第二圖像（的線性化版本）的z緩衝爲屏幕，看它是否可能是Z緩衝問題。黑色像素攝像頭附近：
我試圖改變Z-近和z遠值無任何影響。現在我做的初始化：
glEnable(GL_CULL_FACE);// Cull back facing polygons
glEnable(GL_DEPTH_TEST);
而且我也這樣做，對每一幀：
glClearColor(0.7f, 0.7f, 0.7f, 1.0f);
glClear(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
我認爲這可能是一個面纏繞的問題，所以我試圖禁用GL_CULL_FACE，但它不起作用。我很確定這個模型很好，因爲Blender可以正確渲染它。
我使用這些着色器現在：
// vertex shader
uniform mat4 u_ModelMatrix; // A constant representing the model matrix.
uniform mat4 u_ViewMatrix; // A constant representing the view matrix.
uniform mat4 u_ProjectionMatrix; // A constant representing the projection matrix.
attribute vec4 a_Position; // Per-vertex position information we will pass in.
attribute vec3 a_Normal; // Per-vertex normal information we will pass in.
attribute vec2 a_TexCoordinate; // Per-vertex texture coordinate information we will pass in.
varying vec3 v_Position; // This will be passed into the fragment shader.
varying vec3 v_Normal; // This will be passed into the fragment shader.
varying vec2 v_TexCoordinate; // This will be passed into the fragment shader.
void main()
{
// Transform the vertex into eye space.
mat4 u_ModelViewMatrix = u_ViewMatrix * u_ModelMatrix;
v_Position = vec3(u_ModelViewMatrix * a_Position);
// Pass through the texture coordinate.
v_TexCoordinate = a_TexCoordinate;
// Transform the normal's orientation into eye space.
v_Normal = vec3(u_ModelViewMatrix * vec4(a_Normal, 0.0));
// gl_Position is a special variable used to store the final position.
// Multiply the vertex by the matrix to get the final point in normalized screen coordinates.
gl_Position = u_ProjectionMatrix * u_ModelViewMatrix * a_Position;
}
這是片段着色器：
// fragment shader
uniform sampler2D u_Texture; // The input texture.
uniform int u_TexCount;
varying vec3 v_Position; // Interpolated position for this fragment.
varying vec3 v_Normal; // Interpolated normal for this fragment.
varying vec2 v_TexCoordinate; // Interpolated texture coordinate per fragment.
// The entry point for our fragment shader.
void main()
{
vec3 u_LightPos = vec3(1.0);
// Will be used for attenuation.
float distance = length(u_LightPos - v_Position);
// Get a lighting direction vector from the light to the vertex.
vec3 lightVector = normalize(u_LightPos - v_Position);
// Calculate the dot product of the light vector and vertex normal. If the normal and light vector are
// pointing in the same direction then it will get max illumination.
float diffuse = max(dot(v_Normal, lightVector), 0.0);
// Add attenuation.
diffuse = diffuse * (1.0/distance);
// Add ambient lighting
diffuse = diffuse + 0.2;
diffuse = 1.0;
//gl_FragColor = (diffuse * texture2D(u_Texture, v_TexCoordinate));// Textured version
float d = (2.0 * 0.1)/(100.0 + 0.1 - gl_FragCoord.z * (100.0 - 0.1));
gl_FragColor = vec4(d, d, d, 1.0);// z-buffer render
}
我使用VBO與指數加載幾何形狀和材料。
我當然可以粘貼你認爲這可能是相關的一些其他的代碼，但現在我很高興能得到的是什麼導致這種奇怪的行爲的一些想法，或者一些可能的測試中，我能做到的。