Depth buffer stores a depth (z-coordinate) of a rendered pixel of a 3D scene. Depth buffer is used in Z-buffering (management of image depth coordinates). Because of this depth buffer is often called Z-buffer.
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20 views
Depth test -opengl
Does depth test runs before fragment shader,hence not even processing the fragment with frag shader if fragment is discarded
Or
It first runs the fragment shader and then depth test I.e. fragment ...
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0answers
31 views
How to do Decal Clipping with OpenGL using Depth Buffer comparison?
Basically I'm already drawing decals on top of various flat surfaces and that works great.
As soon as the decal approaches the edge of a surface, naturally it doesn't get clipped.
Is there a way to ...
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0answers
58 views
World-space position from logarithmic depth
After changing my current deferred renderer to use a logarithmic depth buffer I can not work out, for the life of me, how to reconstruct world-space depth from the depth buffer values.
When I had the ...
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0answers
28 views
Depth test against culled objects
I have two cameras rendering 2 sets of geometry. (Achieved by setting clipping plane)
The first set contains two planes, and the second set contains a single plane. Each set sits on its own layer.
(...
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1answer
100 views
What is the math behind rendering isometric with the aid of Depth Maps?
I am currently in the process of designing an Isometric game, and one of the features we are trying to add, is using sprite depth maps to render geometry in the correct order.
The reason we are ...
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2answers
65 views
DX11 Clear Issue, Irregular pattern
So far I've put together a bare minimum of a DirectX 11 application. All it does is clear the window to a random shade of red.
const FLOAT clearColor[4] = { rand() / (float) RAND_MAX, 0.0F, 0.0F, 1....
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1answer
51 views
Z buffer for large vs small objects
Are there common, tried and tested techniques for making sure that when displaying very large and very small objects, in a 3D environment, those objects don't display in front or behind each other?
...
2
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2answers
92 views
Why is my depth buffer texture so bright?
https://www.youtube.com/watch?v=QuvAEqgHrMY&feature=youtu.be
https://www.youtube.com/watch?v=5ob1JsPIGAs&feature=youtu.be
gluPerspective(60, (float)CONTEXT_WIDTH / CONTEXT_HEIGHT, 0.1f, 1.f);...
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3answers
141 views
Process of writing to the depth texture
In openGL, let's say I output one single point from the vertex shader with this value
gl_Position = vec4(2.0,3.0,5.0,7.0);
what exact math operations happen to "z" after leaving the vertex shader?
...
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1answer
61 views
Webgl: is possible to use one color buffer to unsharp masking the depth buffer?
I'm noob to webgl. After reading the tutorials at webglfundamentals.org and "Introduction to Computer Graphics", i'm able to succesfully draw some stuff and the depth buffer without thirty-party ...
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1answer
199 views
How to enable depth test with QOpenGLWidget? It renders black screen
Currently I am writing a small application with Qt and OpenGl and I choosed QOpenGLWidget for rendering graphics.
That's how I declared my widget:
class GLWidget : public QOpenGLWidget, protected ...
4
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1answer
323 views
An invisible object that deletes anything behind it?
I am using augmented reality to put a 3D object on top of a "camera detected" object.
The 3D object can be though of as leaves that go above the real world object but also fall in front / behind / on ...
2
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1answer
175 views
Is it possible to create a homemade depth buffer?
Studying the case of isometric rendering, I'm facing a big and well-known problem : depth sorting.
After many researches it seems that without tile mapping or 'height-leveling' it's impossible to ...
0
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1answer
162 views
Is glxinfo saying that the 980 GTX doesn't support a 32 bit depth buffer?
I've been using the glxinfo command (glxinfo -v) to explore the supported framebuffer configurations. There are two values relating to depth, "depth" and "depthsize." According the source, it appears ...
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1answer
83 views
Image-Space coherence of the z-buffer algorithm
I'm reading Hierarchical z-Buffer Visibility by Ned Greene et al. and they state that
traditional Z buffering makes reasonably good use of image-space coherence in the course of scan conversion.
I ...
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0answers
252 views
Why does reverse depth buffering provide more precision? (with DXGI_FORMAT_D24_UNORM_S8_UINT Datatype layout)
I lately came around methods optimizing the use of the depth buffer, as the easiest solution reverse depth buffering is mentioned but I cannot wrap my head around why I would be gaining a better depth ...
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0answers
56 views
SlimDX 11: Setting Multiple Render Targets
I'm using SlimDX 11 in my managed Direct3D application. I would like to implement deferred shading. I'm having trouble when I try to set a depth stencil surface and multiple render targets at the same ...
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1answer
755 views
Depth Peeling implementation problem: How to render the next layer? (OpenGL)
I try to implement order-independet transparency sticking to the pseudo code in the linked paper (page 4). I can't figure out how they are able to do this in OpenGL.
I am rendering the scene two ...
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2answers
159 views
How to combine depth and stencil tests?
I have a continuous height-mapped mesh to represent landscape. I use the stencil test to create holes in the mesh. I draw holes to the stencil buffer and then use it to discard mesh fragments. ...
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1answer
70 views
OpenGL: strange thing with depth and text rendering
TL;DR I render a scene with M,V,P matrices as always. Than I render something (in this case - text) without any matrices and using separate shaders pair on coordinates with Z = -1. Somehow it's ...
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2answers
133 views
Does Direct3D 11 enable Z-clipping/discard by default?
I'm rendering simple 2D figures in DirectX 11.1 and I cannot get Z-values to be rendered; all pixels with Z != 0 get discarded. I'm doing proper world transform as far as I know. X/Y translations work....
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1answer
47 views
Depth testing before fragment shader
Accoring to this, depth testing is usually performed after the fragment shader stage. Why is that? I thought that a fragment is sent with its depth value to the FS, then the depth test happens before ...
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1answer
128 views
OpenGL Picking: How to avoid entities?
I have a terrain and entities(npc, house...).
I'm able to convert screen coordinates to world coordinates with the glReadPixels function:
glReadPixels(mousePosition.x, mousePosition.y, 1, 1, ...
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1answer
233 views
Render scene depth to texture via FBO?
I'm trying to render my scene's depth via FBO and Render To Texture. I have a scene that I'm rendering to a texture, then render that texture to a fullscreen quad in a second pass using a fragment ...
1
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1answer
605 views
Raymarching on a Hi-Z buffer in GLSL
So I'm trying to implement Screen Space Reflections using a Hierarchical z-Buffer in GLSL. I'm following the approach from GPU Gems 5 and the Frostbite presentation linked here ("Stochastic Screen-...
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1answer
111 views
How to use default framebuffer's depth/stencil when rendering to a texture?
Is it possible to use the default framebuffer depth buffer when rendering to a texture (instead of using a depth texture)?
The Idea is to continue to render part of the scene normally but on a ...
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1answer
69 views
Write depth value to a render target
I want to write depth value to a render target, not depth buffer. So I output the clip space position from vertex shader and divide by w on pixel shader.
Here is the code of how I do this
// Vertex ...
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1answer
614 views
SSAO, depth buffer linearization (?)
I'm trying to implement SSAO in my application but it doesn't look as it should. I think that the problem is with depth buffer linearization but I tried almost all methods which I found on the Web and ...
3
votes
1answer
125 views
Strange depth map projection
I'm trying to implement depth-only SSAO and for that, I render a depth map into a texture and pass it to my SSAO shader which then uses it.
The problem is that when I try to output the depth map ...
4
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0answers
397 views
OpenGL Depth Cubemap with Geometry Shader Not Rendering Correctly
I was having some trouble with cubemaps in OpenGL, and was hoping to get some help. I've been following a tutorial about point light shadow mapping using cubemaps, where a geometry shader is used to ...
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1answer
184 views
What are the units when reading depth using glReadPixels()?
Suppose I use glReadPixels() to read the depth of a pixel from the depth buffer. What are the units of this? Is it the distance from the camera? Or the distance from the near clip plane? And is the ...
4
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2answers
517 views
Render Occluded pixels to gray color
In 3d space, objects can be occluded by another objects.
By depth testing, the occluded faces are skipped rendering. Only the nearest(smallest) depth value pixels are drawn.
But, sometime we need to ...
8
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3answers
821 views
Using full resolution of depth buffer for 2D rendering
I'm working on a front-to-back renderer for a 2D engine using an orthographic projection. I want to use the depth buffer to avoid overdraw. I have a 16-bit depth buffer, a camera at Z=100 looking at Z=...
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3answers
235 views
Grab depth buffer with unlockable D3DFORMAT
I'm currently piggy backing on a mod framework (Multitheft Auto) and trying to read the depth buffer in D3DFMT_D24S8 (DirectX9). I can read it if I change the format to D3DFMT_D32F_LOCKABLE and then ...
3
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1answer
2k views
Creating polygons with separate outline/fill colors in OpenGL
Subject
I am creating a terrain map with triangle strips and I would like to make the bodies of the triangles black, but have their outlines be colored.
Problem
The solution appears to be to draw ...
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1answer
149 views
Does glScissor affect stencil and depth buffer operations?
I know glScissor() affects glColorMask() and glDepthMask(), but does it affect the stencil and depth buffers?
For example:
glEnable(GL_DEPTH_TEST);
glEnable(GL_SCISSOR_TEST);
glEnable(...
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3answers
248 views
Is computing depth in a pixel shader bad? Can I reduce fillrate by moving depth calc to vertex shader?
I have a DX10 game that is fillrate bound. One of the things I've been realizing may be contributing to this is that I compute depth in the pixel shader (the game uses a logarithmic depth buffer to ...
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1answer
83 views
Wrong distance in Depth-buffer
I am currently trying to get the Depth Buffer as a texture to use it for edge detection algorithms. Since XNA4 does not allow direct access to the Depth Buffer as texture i have to render it into a ...
5
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1answer
2k views
unity 5 how to get a shadowmap
I'm writing a custom shader in unity 5 that requires a shadowmap (not just for drawing shadows but also for different computations involving scattering particles through fog). Does anybody know how to ...
0
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2answers
421 views
Z-Value of clip-space position is always 1.0
I render a lot of quads on the screen into z direction (20 x 2000). I want to get the depth value in a final render target. But it looks like z is always 1.0f. I checked the result with the OpenGL ...
0
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1answer
2k views
Getting the real fragment depth in GLSL
I am trying to write a simple GLSL shader that just renders the real (not normalized) depth of a fragment as a floating point value.
So far, I've figured out how to get the depth of a vertex, and ...
1
vote
1answer
2k views
Discard Transparent Pixels in Z-Buffer
I am building a 2D game using sprites. I'd like to use the z-buffer to aid with shading.
For that I need Unity to write only opaque pixels to the z-buffer (aka depth buffer). In Unity, sprites are ...
1
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1answer
6k views
Unity3D sprites vs Mesh Quads - Depth, Blending, Shadows
I'm new to unity but not new to game development. In my OpenGL ES 2.0 (mobile) games I create a vertex array of all my "sprites" and stuff it in a VBO. Then draw them as I need them one at a time, ...
0
votes
1answer
2k views
How to disable depth buffer in Directx11
For now i know what i must use OMSetDepthStencilState. In the beginning i must create two states and change them every time i need another. For now i have this and it doesn't work, i.e. objects ...
4
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1answer
847 views
How to compute point in view space from depth?
I am trying to implement do some screen space rendering but after looking over the web I still don't find answers to some doubts.
First, I need to compute the point in view space from a value in the ...
5
votes
1answer
581 views
Modifying depth values in PixelShader (SharpDX)
I'm relatively new to DirectX, and am currently converting some WPF 2D graphics code that displays geo-located sonar returns. I am using SharpDX, and rendering via a D3DImage.
I've got the basics ...
2
votes
1answer
984 views
Triangles go missing as Z changes
I'm rendering a height map using shader-based OpenGL (3.3 to be precise). The height map data is from a grayscale bitmap (2D array of bytes). The dimension of the bitmap is 256 x 256.
With this data, ...
3
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1answer
323 views
Shadow mapping. I don't understand what to do after creating the depth texture
I'm taking an intro to computer graphics course, so this is something we haven't touched on.
I am reading this tutorial http://www.opengl-tutorial.org/intermediate-tutorials/tutorial-16-shadow-...
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0answers
34 views
Artefact in VSM as if GL_DEPTH_TEST disabled
I am trying to implement VSM and I incurred in a strange issue. I render them as follow:
glUseProgram(shadowMapProgramID);
glEnableVertexAttribArray(0);
glBindFramebuffer(GL_FRAMEBUFFER, ...
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2answers
2k views
How do I sample a Depth/Stencil Texture in HLSL?
I am shadow mapping in Direct3D 9. I'm trying to avoid rendering depth to a 32-bit render target. So, I've created a depth/stencil texture( a texture w/usage Depth/Stencil ). When I render I do this:
...
