I really do not understand what the validation error means. There is no alignment requirement for vertex shader attributes in VkPhysicalDeviceLimits.
Here is the full error:
[2022-02-07.20:42:38]: Validation Error: [ VUID-vkCmdDrawIndexed-None-02721 ] Object 0: handle = 0xfef35a00000000a0, type = VK_OBJECT_TYPE_BUFFER; Object 1: handle = 0xa56ac00000000d4, type = VK_OBJECT_TYPE_PIPELINE; | MessageID = 0x24afafc5 | vkCmdDrawIndexed: Invalid attribAddress alignment for vertex attribute 0, VK_FORMAT_R32G32B32_SFLOAT,from of VkPipeline 0xa56ac00000000d4[] and vertex VkBuffer 0xfef35a00000000a0[]. The Vulkan spec states: For a given vertex buffer binding, any attribute data fetched must be entirely contained within the corresponding vertex buffer binding, as described in Vertex Input Description (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-vkCmdDrawIndexed-None-02721)
Here is my shader.
#version 450 core
layout (location = 0) in vec3 inPosition;
layout (location = 1) in vec3 inNormal;
layout (location = 2) in vec2 inTexCoord;
// Instancing Data
//layout (location = 3) in vec2 XYOffset;
layout (binding = 0) uniform View_Projection {
mat4 u_View;
mat4 u_Projection;
};
layout (binding = 1) uniform Model {
mat4 u_Model;
mat4 u_NormalModel; // transpose(inverse(u_Model))
};
layout (location = 0) out vec3 Normal;
layout (location = 1) out vec2 TexCoord;
void main() {
Normal = mat3(u_NormalModel) * inNormal;
TexCoord = inTexCoord;
//vec4 InstancePosition = vec4(inPosition.xy + XYOffset, inPosition.z, 1.0);
//gl_Position = u_Projection * u_View * u_Model * InstancePosition;
gl_Position = u_Projection * u_View * u_Model * vec4(inPosition, 1.0);
}
UPDATE 1:
struct VulkanPipelineVertexInput
{
VkPipelineVertexInputStateCreateInfo createInfo;
std::vector<VkVertexInputBindingDescription> binding_descriptions;
std::vector<VkVertexInputAttributeDescription> attribute_descriptions;
std::vector<VkVertexInputBindingDivisorDescriptionEXT> divisor_description;
VkPipelineVertexInputDivisorStateCreateInfoEXT divisorCreateInfo;
};
static VulkanPipelineVertexInput Vulkan_Internal_PipelineState_InitalizeVertexInput(IPipelineLayout layout)
{
VulkanPipelineVertexInput input_state;
PipelineVertexInputDescription &input_description = layout->m_vertex_input_description;
if(input_description.m_input_elements.size() > 0)
{
int lastBinding = -1;
for(const auto& element : input_description.m_input_elements)
{
VkVertexInputAttributeDescription attribute;
attribute.binding = element.m_binding_id;
attribute.format = element.m_vk_format;
attribute.location = element.m_location;
attribute.offset = element.m_offset;
input_state.attribute_descriptions.push_back(attribute);
if(lastBinding != element.m_binding_id)
{
lastBinding = element.m_binding_id;
VkVertexInputBindingDescription binding_description;
binding_description.binding = element.m_binding_id;
binding_description.inputRate = element.m_per_instance ? VK_VERTEX_INPUT_RATE_INSTANCE : VK_VERTEX_INPUT_RATE_VERTEX;
binding_description.stride = element.m_stride;
if(element.m_per_instance)
{
VkVertexInputBindingDivisorDescriptionEXT divisor_description;
divisor_description.binding = element.m_binding_id;
divisor_description.divisor = element.m_divisor_rate;
input_state.divisor_description.push_back(divisor_description);
}
input_state.binding_descriptions.push_back(binding_description);
}
}
}
input_state.createInfo.sType = VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO;
input_state.createInfo.pNext = input_state.divisor_description.size() > 0 ? &input_state.divisorCreateInfo : nullptr;
input_state.createInfo.flags = 0;
input_state.createInfo.vertexBindingDescriptionCount = input_state.binding_descriptions.size();
input_state.createInfo.pVertexBindingDescriptions = input_state.binding_descriptions.data();
input_state.createInfo.vertexAttributeDescriptionCount = input_state.attribute_descriptions.size();
input_state.createInfo.pVertexAttributeDescriptions = input_state.attribute_descriptions.data();
return input_state;
}
UPDATE 2:
This code does render, however some geometry is shifted.
Render Output
Vertex attributes must be naturally aligned on the primitive type. For VK_FORMAT_R32G32B32_SFLOAT this means a 4 byte boundary.
Section 22.4.1 in the Vulkan 1.3 spec:
For each attribute, raw data is extracted starting at attribAddress and is converted from the
VkVertexInputAttributeDescription’s format to either floating-point, unsigned integer, or signed
integer based on the base type of the format; the base type of the format must match the base type
of the input variable in the shader. The input variable in the shader must be declared as a 64-bit
data type if and only if format is a 64-bit data type. If format is a packed format, attribAddress must
be a multiple of the size in bytes of the whole attribute data type as described in Packed Formats.
Otherwise, attribAddress must be a multiple of the size in bytes of the component type indicated by
format (see Formats).
https://github.com/KhronosGroup/Vulkan-ValidationLayers/issues/3733
I figured it out!!!!!!!!! I thought this was a driver bug.
I opened the program in RenderDoc and it showed that the vertex buffer had an offset of 1
The problem was setting the vkCmdSetVertexBuffers wrong. vkCmdSetVertexBuffers requires an array of VkDeviceSize[] pOffsets even if you don't use them. I made a typo, writing VkDeviceSize[1] pOffsets = {1} instead of VkDeviceSize[1] = {0}
I am using Assimp to load an FBX model with animation (created in Blender) into my DirectX 12 game, but I'm experiencing a very frustrating bug with the animation rendered by the game application.
The test model is a simple 'flagpole' containing four bones like so:
Bone0 -> Bone1 -> Bone2 -> Bone3
The model renders correctly in its rest pose when the keyframe animation is bypassed.
The model also renders and animates properly when the animation rotates the model only by the root bone (Bone0).
However, when importing a model that rotates at the first joint (i.e. at Bone1), the vertices clustered around each joint seem 'stuck' in their original positions, while the vertices surrounding the 'bones' proper appear to follow through with the correct animation.
The result is a crappy zigzag of stretched geometry like so:
Instead the model should resemble an 'allen-key' shape at the end of its animation pose, as shown by the same model rendered in the AssimpViewer utility tool:
Since the model is rendering correctly in AssimpViewer, it's reasonable to assume there are no issues with the FBX file exported by Blender. I then checked and confirmed that the vertices 'stuck' around the joints did indeed have their vertex weights correctly assigned by the game loading code.
The C++ model loading and animation code is based on the popular OGLDev tutorial: https://ogldev.org/www/tutorial38/tutorial38.html
Now the infuriating thing is, since the AssimpViewer tool was correctly rendering the model animation, I also copied in the SceneAnimator and AnimEvaluator classes from that tool to generate the final bone transforms via that code branch as well... only to end up with exactly the same zigzag bug in the game!
I'm reasonably confident there aren't any issues with finding the bone hierarchy structure at initialization, so here are the key functions that traverse the hierarchy and interpolate key frames each frame.
VOID Mesh::ReadNodeHeirarchy(FLOAT animationTime, CONST aiNode* pNode, CONST aiAnimation* pAnim, CONST aiMatrix4x4 parentTransform)
{
std::string nodeName(pNode->mName.data);
// nodeTransform is a relative transform to parent node space
aiMatrix4x4 nodeTransform = pNode->mTransformation;
CONST aiNodeAnim* pNodeAnim = FindNodeAnim(pAnim, nodeName);
if (pNodeAnim)
{
// Interpolate scaling and generate scaling transformation matrix
aiVector3D scaling(1.f, 1.f, 1.f);
CalcInterpolatedScaling(scaling, animationTime, pNodeAnim);
// Interpolate rotation and generate rotation transformation matrix
aiQuaternion rotationQ (1.f, 0.f, 0.f, 0.f);
CalcInterpolatedRotation(rotationQ, animationTime, pNodeAnim);
// Interpolate translation and generate translation transformation matrix
aiVector3D translat(0.f, 0.f, 0.f);
CalcInterpolatedPosition(translat, animationTime, pNodeAnim);
// build the SRT transform matrix
nodeTransform = aiMatrix4x4(rotationQ.GetMatrix());
nodeTransform.a1 *= scaling.x; nodeTransform.b1 *= scaling.x; nodeTransform.c1 *= scaling.x;
nodeTransform.a2 *= scaling.y; nodeTransform.b2 *= scaling.y; nodeTransform.c2 *= scaling.y;
nodeTransform.a3 *= scaling.z; nodeTransform.b3 *= scaling.z; nodeTransform.c3 *= scaling.z;
nodeTransform.a4 = translat.x; nodeTransform.b4 = translat.y; nodeTransform.c4 = translat.z;
}
aiMatrix4x4 globalTransform = parentTransform * nodeTransform;
if (m_boneMapping.find(nodeName) != m_boneMapping.end())
{
UINT boneIndex = m_boneMapping[nodeName];
// the global inverse transform returns us to mesh space!!!
m_boneInfo[boneIndex].FinalTransform = m_globalInverseTransform * globalTransform * m_boneInfo[boneIndex].BoneOffset;
//m_boneInfo[boneIndex].FinalTransform = m_boneInfo[boneIndex].BoneOffset * globalTransform * m_globalInverseTransform;
m_shaderTransforms[boneIndex] = aiMatrixToSimpleMatrix(m_boneInfo[boneIndex].FinalTransform);
}
for (UINT i = 0u; i < pNode->mNumChildren; i++)
{
ReadNodeHeirarchy(animationTime, pNode->mChildren[i], pAnim, globalTransform);
}
}
VOID Mesh::CalcInterpolatedRotation(aiQuaternion& out, FLOAT animationTime, CONST aiNodeAnim* pNodeAnim)
{
UINT rotationKeys = pNodeAnim->mNumRotationKeys;
// we need at least two values to interpolate...
if (rotationKeys == 1u)
{
CONST aiQuaternion& key = pNodeAnim->mRotationKeys[0u].mValue;
out = key;
return;
}
UINT rotationIndex = FindRotation(animationTime, pNodeAnim);
UINT nextRotationIndex = (rotationIndex + 1u) % rotationKeys;
assert(nextRotationIndex < rotationKeys);
CONST aiQuatKey& key = pNodeAnim->mRotationKeys[rotationIndex];
CONST aiQuatKey& nextKey = pNodeAnim->mRotationKeys[nextRotationIndex];
FLOAT deltaTime = FLOAT(nextKey.mTime) - FLOAT(key.mTime);
FLOAT factor = (animationTime - FLOAT(key.mTime)) / deltaTime;
assert(factor >= 0.f && factor <= 1.f);
aiQuaternion::Interpolate(out, key.mValue, nextKey.mValue, factor);
}
I've just included the rotation interpolation here, since the scaling and translation functions are identical. For those unaware, Assimp's aiMatrix4x4 type follows a column-vector math convention, so I haven't messed with original matrix multiplication order.
About the only deviation between my code and the two Assimp-based code branches I've adopted is the requirement to convert the final transforms from aiMatrix4x4 types into a DirectXTK SimpleMath Matrix (really an XMMATRIX) with this conversion function:
Matrix Mesh::aiMatrixToSimpleMatrix(CONST aiMatrix4x4 m)
{
return Matrix
(m.a1, m.a2, m.a3, m.a4,
m.b1, m.b2, m.b3, m.b4,
m.c1, m.c2, m.c3, m.c4,
m.d1, m.d2, m.d3, m.d4);
}
Because of the column-vector orientation of aiMatrix4x4 Assimp matrices, the final bone transforms are not transposed for HLSL consumption. The array of final bone transforms are passed to the skinning vertex shader constant buffer as follows.
commandList->SetPipelineState(m_psoForwardSkinned.Get()); // set PSO
// Update vertex shader with current bone transforms
CONST std::vector<Matrix> transforms = m_assimpModel.GetShaderTransforms();
VSBonePassConstants vsBoneConstants{};
for (UINT i = 0; i < m_assimpModel.GetNumBones(); i++)
{
// We do not transpose bone matrices for HLSL because the original
// Assimp matrices are column-vector matrices.
vsBoneConstants.boneTransforms[i] = transforms[i];
//vsBoneConstants.boneTransforms[i] = transforms[i].Transpose();
//vsBoneConstants.boneTransforms[i] = Matrix::Identity;
}
GraphicsResource vsBoneCB = m_graphicsMemory->AllocateConstant(vsBoneConstants);
vsPerObjects.gWorld = m_assimp_world.Transpose(); // vertex shader per object constant
vsPerObjectCB = m_graphicsMemory->AllocateConstant(vsPerObjects);
commandList->SetGraphicsRootConstantBufferView(RootParameterIndex::VSBoneConstantBuffer, vsBoneCB.GpuAddress());
commandList->SetGraphicsRootConstantBufferView(RootParameterIndex::VSPerObjConstBuffer, vsPerObjectCB.GpuAddress());
//commandList->SetGraphicsRootDescriptorTable(RootParameterIndex::ObjectSRV, m_shaderTextureHeap->GetGpuHandle(ShaderTexDescriptors::SuzanneDiffuse));
commandList->SetGraphicsRootDescriptorTable(RootParameterIndex::ObjectSRV, m_shaderTextureHeap->GetGpuHandle(ShaderTexDescriptors::DefaultDiffuse));
for (UINT i = 0; i < m_assimpModel.GetMeshSize(); i++)
{
commandList->IASetVertexBuffers(0u, 1u, &m_assimpModel.meshEntries[i].GetVertexBufferView());
commandList->IASetIndexBuffer(&m_assimpModel.meshEntries[i].GetIndexBufferView());
commandList->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
commandList->DrawIndexedInstanced(m_assimpModel.meshEntries[i].GetIndexCount(), 1u, 0u, 0u, 0u);
}
Please note I am using the Graphics Resource memory management helper object found in the DirectXTK12 library in the code above. Finally, here's the skinning vertex shader I'm using.
// Luna (2016) lighting model adapted from Moller
#define MAX_BONES 4
// vertex shader constant data that varies per object
cbuffer cbVSPerObject : register(b3)
{
float4x4 gWorld;
//float4x4 gTexTransform;
}
// vertex shader constant data that varies per frame
cbuffer cbVSPerFrame : register(b5)
{
float4x4 gViewProj;
float4x4 gShadowTransform;
}
// bone matrix constant data that varies per object
cbuffer cbVSBonesPerObject : register(b9)
{
float4x4 gBoneTransforms[MAX_BONES];
}
struct VertexIn
{
float3 posL : SV_POSITION;
float3 normalL : NORMAL;
float2 texCoord : TEXCOORD0;
float3 tangentU : TANGENT;
float4 boneWeights : BONEWEIGHT;
uint4 boneIndices : BONEINDEX;
};
struct VertexOut
{
float4 posH : SV_POSITION;
//float3 posW : POSITION;
float4 shadowPosH : POSITION0;
float3 posW : POSITION1;
float3 normalW : NORMAL;
float2 texCoord : TEXCOORD0;
float3 tangentW : TANGENT;
};
VertexOut VS_main(VertexIn vin)
{
VertexOut vout = (VertexOut)0.f;
// Perform vertex skinning.
// Ignore BoneWeights.w and instead calculate the last weight value
// to ensure all bone weights sum to unity.
float4 weights = vin.boneWeights;
//weights.w = 1.f - dot(weights.xyz, float3(1.f, 1.f, 1.f));
//float4 weights = { 0.f, 0.f, 0.f, 0.f };
//weights.x = vin.boneWeights.x;
//weights.y = vin.boneWeights.y;
//weights.z = vin.boneWeights.z;
weights.w = 1.f - (weights.x + weights.y + weights.z);
float4 localPos = float4(vin.posL, 1.f);
float3 localNrm = vin.normalL;
float3 localTan = vin.tangentU;
float3 objPos = mul(localPos, (float4x3)gBoneTransforms[vin.boneIndices.x]).xyz * weights.x;
objPos += mul(localPos, (float4x3)gBoneTransforms[vin.boneIndices.y]).xyz * weights.y;
objPos += mul(localPos, (float4x3)gBoneTransforms[vin.boneIndices.z]).xyz * weights.z;
objPos += mul(localPos, (float4x3)gBoneTransforms[vin.boneIndices.w]).xyz * weights.w;
float3 objNrm = mul(localNrm, (float3x3)gBoneTransforms[vin.boneIndices.x]) * weights.x;
objNrm += mul(localNrm, (float3x3)gBoneTransforms[vin.boneIndices.y]) * weights.y;
objNrm += mul(localNrm, (float3x3)gBoneTransforms[vin.boneIndices.z]) * weights.z;
objNrm += mul(localNrm, (float3x3)gBoneTransforms[vin.boneIndices.w]) * weights.w;
float3 objTan = mul(localTan, (float3x3)gBoneTransforms[vin.boneIndices.x]) * weights.x;
objTan += mul(localTan, (float3x3)gBoneTransforms[vin.boneIndices.y]) * weights.y;
objTan += mul(localTan, (float3x3)gBoneTransforms[vin.boneIndices.z]) * weights.z;
objTan += mul(localTan, (float3x3)gBoneTransforms[vin.boneIndices.w]) * weights.w;
vin.posL = objPos;
vin.normalL = objNrm;
vin.tangentU.xyz = objTan;
//vin.posL = posL;
//vin.normalL = normalL;
//vin.tangentU.xyz = tangentL;
// End vertex skinning
// transform to world space
float4 posW = mul(float4(vin.posL, 1.f), gWorld);
vout.posW = posW.xyz;
// assumes nonuniform scaling, otherwise needs inverse-transpose of world matrix
vout.normalW = mul(vin.normalL, (float3x3)gWorld);
vout.tangentW = mul(vin.tangentU, (float3x3)gWorld);
// transform to homogenous clip space
vout.posH = mul(posW, gViewProj);
// pass texcoords to pixel shader
vout.texCoord = vin.texCoord;
//float4 texC = mul(float4(vin.TexC, 0.0f, 1.0f), gTexTransform);
//vout.TexC = mul(texC, gMatTransform).xy;
// generate projective tex-coords to project shadow map onto scene
vout.shadowPosH = mul(posW, gShadowTransform);
return vout;
}
Some last tests I tried before posting:
I tested the code with a Collada (DAE) model exported from Blender, only to observe the same distorted zigzagging in the Win32 desktop application.
I also confirmed the aiScene object for the loaded model returns an identity matrix for the global root transform (also verified in AssimpViewer).
I have stared at this code for about a week and am going out of my mind! Really hoping someone can spot what I have missed. If you need more code or info, please ask!
This seems to be a bug with the published code in the tutorials / documentation. It would be great if you could open an issue-report here: Assimp-Projectpage on GitHub .
It's taken almost another two weeks of pain, but I finally found the bug. It was in my own code, and it was self-inflicted. Before I show the solution, I should explain the further troubleshooting I did to get there.
After losing faith with Assimp (even though the AssimpViewer tool was animating my model correctly), I turned to the FBX SDK. The FBX ViewScene command line utility tool that's available as part of the SDK was also showing and animating my model properly, so I had hope...
So after a few days reviewing the FBX SDK tutorials, and taking another week to write an FBX importer for my Windows desktop game, I loaded my model and... saw exactly the same zig-zag animation anomaly as the version loaded by Assimp!
This frustrating outcome meant I could at least eliminate Assimp and the FBX SDK as the source of the problem, and focus again on the vertex shader. The shader I'm using for vertex skinning was adopted from the 'Character Animation' chapter of Frank Luna's text. It was identical in every way, which led me to recheck the C++ vertex structure declared on the application side...
Here's the C++ vertex declaration for skinned vertices:
struct Vertex
{
// added constructors
Vertex() = default;
Vertex(FLOAT x, FLOAT y, FLOAT z,
FLOAT nx, FLOAT ny, FLOAT nz,
FLOAT u, FLOAT v,
FLOAT tx, FLOAT ty, FLOAT tz) :
Pos(x, y, z),
Normal(nx, ny, nz),
TexC(u, v),
Tangent(tx, ty, tz) {}
Vertex(DirectX::SimpleMath::Vector3 pos,
DirectX::SimpleMath::Vector3 normal,
DirectX::SimpleMath::Vector2 texC,
DirectX::SimpleMath::Vector3 tangent) :
Pos(pos), Normal(normal), TexC(texC), Tangent(tangent) {}
DirectX::SimpleMath::Vector3 Pos;
DirectX::SimpleMath::Vector3 Normal;
DirectX::SimpleMath::Vector2 TexC;
DirectX::SimpleMath::Vector3 Tangent;
FLOAT BoneWeights[4];
BYTE BoneIndices[4];
//UINT BoneIndices[4]; <--- YOU HAVE CAUSED ME A MONTH OF PAIN
};
Quite early on, being confused by Luna's use of BYTE to store the array of bone indices, I changed this structure element to UINT, figuring this still matched the input declaration shown here:
static CONST D3D12_INPUT_ELEMENT_DESC inputElementDescSkinned[] =
{
{ "SV_POSITION", 0u, DXGI_FORMAT_R32G32B32_FLOAT, 0u, D3D12_APPEND_ALIGNED_ELEMENT, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0u },
{ "NORMAL", 0u, DXGI_FORMAT_R32G32B32_FLOAT, 0u, D3D12_APPEND_ALIGNED_ELEMENT, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0u },
{ "TEXCOORD", 0u, DXGI_FORMAT_R32G32_FLOAT, 0u, D3D12_APPEND_ALIGNED_ELEMENT, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0u },
{ "TANGENT", 0u, DXGI_FORMAT_R32G32B32_FLOAT, 0u, D3D12_APPEND_ALIGNED_ELEMENT, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0u },
//{ "BINORMAL", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, D3D12_APPEND_ALIGNED_ELEMENT, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 },
{ "BONEWEIGHT", 0u, DXGI_FORMAT_R32G32B32A32_FLOAT, 0u, D3D12_APPEND_ALIGNED_ELEMENT, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0u },
{ "BONEINDEX", 0u, DXGI_FORMAT_R8G8B8A8_UINT, 0u, D3D12_APPEND_ALIGNED_ELEMENT, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0u },
};
Here was the bug. By declaring UINT in the vertex structure for bone indices, four bytes were being assigned to store each bone index. But in the vertex input declaration, the DXGI_FORMAT_R8G8B8A8_UINT format specified for the "BONEINDEX" was assigning one byte per index. I suspect this data type and format size mismatch was resulting in only one valid bone index being able to fit in the BONEINDEX element, and so only one index value was passed to the vertex shader each frame, instead of the whole array of four indices for correct bone transform lookups.
So now I've learned... the hard way... why Luna had declared an array of BYTE for bone indices in the original C++ vertex structure.
I hope this experience will be of value to someone else, and always be careful changing code from your original learning sources.
In Vulkan, I had written a simple program to draw lines with fixed color, with simple vertex shader and fragement shader. But the colors input to fragment shaders are different than what is set in vertices. I checked with RenderDoc, and the colors passed to the vertex shader are correct (1,1,1,1) for both vertices of a line and also checked its output, its also same. But in Fragment shader, the colors I am getting are (1,1,0,1). Dont understand why this is happening. Irrespetive of what colors vertex shader emit, the input in fragment shader is always yellow.
Vertex shader:
layout(location = 0) in vec4 position;
layout(location = 1) in vec4 color;
layout(location = 2) in vec2 texcoord;
out vec4 io_color;
out vec2 io_uv;
out vec4 io_position2;
layout(std140, binding = 0) uniform UniformBlock_uTransform
{
mat4 uTransform;
};
layout(std140, binding = 1) uniform UniformBlock_uTransform2
{
mat4 uTransform2;
};
void main ()
{
io_uv = texcoord;
io_color = vec4(1,1,1,1); //Just to debug it
gl_Position = uTransform * position;
io_position2 = uTransform2 * position;
}
//Fragement :
in vec4 io_color;
layout(location = 0) out vec4 result;
void main ()
{
result = io_color;
}
Try adding output and input layout qualifiers to the values you pass from one shader to the other to ensure that they actually point to the same location:
VS:
layout (location = 0) out vec4 io_color;
FS:
layout (location = 0) in vec4 io_color;
I recommend always using that syntax to connect shader out- and inputs.
Check if color write mask is not disabled for blue channel.
I'm trying to figure out how to put different textures into different texture units and choose which texture to draw with. I have the following code in my onDrawFrame() method
int[] texture = new int[7];
texture[0] =TextureHelper.loadTexture(mActivityContext,R.drawable.texture1);
texture[1] =TextureHelper.loadTexture(mActivityContext,R.drawable.texture2);
texture[2] =TextureHelper.loadTexture(mActivityContext,R.drawable.texture3);
texture[3] =TextureHelper.loadTexture(mActivityContext,R.drawable.texture4);
texture[4] =TextureHelper.loadTexture(mActivityContext,R.drawable.texture5);
texture[5] =TextureHelper.loadTexture(mActivityContext,R.drawable.texture6);
texture[6] =TextureHelper.loadTexture(mActivityContext,R.drawable.texture7);
for (int i = 0; i < 7; i ++) {
GLES20.glActiveTexture(GLES20.GL_TEXTURE0 + i);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texture[i]);
GLES20.glUniform1i(mTextureUniformHandle, i);
Matrix.setIdentityM(mModelMatrix, 0);
Matrix.translateM(mModelMatrix, 0, -0.60f + 0.2f * i, 0.0f, 0.0f);
draw();
}
What this is supposed to do is load seven different textures into separate texture units and draw cubes, each cube with a different texture. However, what ends up happening is that all of the cubes end up being drawn with the first texture.
It works correctly if I change GLES20.glActiveTexture(GLES20.GL_TEXTURE0 + i) to GLES20.glActiveTexture(GLES20.GL_TEXTURE0) and GLES20.glUniform1i(mTextureUniformHandle, i) to GLES20.glUniform1i(mTextureUniformHandle, 0), but that just uses a single texture unit and replaces the texture in that unit every time, which is not what I want to do.
What am I doing wrong?
Thanks in advance.
EDIT:
Vertex shader:
"uniform mat4 u_MVPMatrix;" + // A constant representing the
// combined
// model/view/projection matrix.
"uniform mat4 u_MVMatrix;" + // A constant representing the
// combined model/view matrix.
"attribute vec4 a_Position;" + // Per-vertex position
// information we will pass in.
"attribute vec4 a_Color;" + // Per-vertex color 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 vec4 v_Color;" + // This will be passed into the
// fragment shader.
"varying vec2 v_TexCoordinate;" + // This will be passed into
// the fragment shader.
// The entry point for our vertex shader.
"void main()" + "{" +
// Transform the vertex into eye space.
"v_Position = vec3(u_MVMatrix * a_Position);" +
// Pass through the color.
"v_Color = a_Color;" +
// Pass through the texture coordinate.
"v_TexCoordinate = a_TexCoordinate;" +
// 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_MVPMatrix * a_Position;" + "} ";
Fragment shader:
"precision mediump float;" + // Set the default precision to medium. We don't need as high of a
// precision in the fragment shader.
"uniform sampler2D u_Texture;" + // The input texture.
"varying vec3 v_Position;" + // Interpolated position for this fragment.
"varying vec4 v_Color;" + // This is the color from the vertex shader interpolated across the
// triangle per fragment.
"varying vec2 v_TexCoordinate;" + // Interpolated texture coordinate per fragment.
// The entry point for our fragment shader.
"void main()" +
"{" +
// Multiply the color by the diffuse illumination level and texture value to get final output color.
"gl_FragColor = (v_Color * texture2D(u_Texture, v_TexCoordinate));" +
"}";
draw() method:
public void draw() {
// Pass in the position information
mCubePositions.position(0);
GLES20.glVertexAttribPointer(mPositionHandle, mPositionDataSize, GLES20.GL_FLOAT, false, 0, mCubePositions);
GLES20.glEnableVertexAttribArray(mPositionHandle);
// Pass in the color information
mCubeColors.position(0);
GLES20.glVertexAttribPointer(mColorHandle, mColorDataSize, GLES20.GL_FLOAT, false, 0, mCubeColors);
GLES20.glEnableVertexAttribArray(mColorHandle);
// Pass in the texture coordinate information
mCubeTextureCoordinates.position(0);
GLES20.glVertexAttribPointer(mTextureCoordinateHandle, mTextureCoordinateDataSize, GLES20.GL_FLOAT, false, 0, mCubeTextureCoordinates);
GLES20.glEnableVertexAttribArray(mTextureCoordinateHandle);
// This multiplies the view matrix by the model matrix, and stores the
// result in the MVP matrix
// (which currently contains model * view).
Matrix.multiplyMM(mMVPMatrix, 0, mViewMatrix, 0, mModelMatrix, 0);
// Pass in the modelview matrix.
GLES20.glUniformMatrix4fv(mMVMatrixHandle, 1, false, mMVPMatrix, 0);
// This multiplies the modelview matrix by the projection matrix, and
// stores the result in the MVP matrix
// (which now contains model * view * projection).
Matrix.multiplyMM(mMVPMatrix, 0, mProjectionMatrix, 0, mMVPMatrix, 0);
// Pass in the combined matrix.
GLES20.glUniformMatrix4fv(mMVPMatrixHandle, 1, false, mMVPMatrix, 0);
// Draw the cube.
GLES20.glDrawArrays(GLES20.GL_TRIANGLES, 0, 6);
}
Assigning mTextureUniformHandle :
mTextureUniformHandle = GLES20.glGetUniformLocation(mProgramHandle, "u_Texture");
Lately I've been searching for multiple textures in fragment shader and came across this Binding textures to samplers
from which I got the following to work:
In onSurfaceCreated or onSurfaceChanged:
Load shaders (attach and link) and get uniform locations for sampler2D (and other variables):
normalMapLoc = GLES20.glGetUniformLocation(shaderProgram, "normalMap");
shadowMapLoc = GLES20.glGetUniformLocation(shaderProgram, "shadowMap");
Load textures:
GLES20.glGenTextures(2, textures, 0);
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textures[0]);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_NEAREST);
GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
bitmap.recycle();
GLES20.glActiveTexture(GLES20.GL_TEXTURE1);
GLES20.glBindTexture(GL10.GL_TEXTURE_COORD_ARRAY, textures[1]);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_NEAREST);
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA, width, height, 0, GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE, mColorBuffer);
GLES20.glUniform1i(normalMapLoc, 0); // Texture unit 0 is for normal images.
GLES20.glUniform1i(shadowMapLoc, 1); // Texture unit 1 is for shadow maps.
In onDrawFrame:
GLES20.glClearColor(0f, 0f, 0f, 0f);
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
// pass variables to the fragment shader
...
// get handle to vertex shader's Position member, etcetera
int mPositionHandle = GLES20.glGetAttribLocation(shaderProgram, "vPosition");
GLES20.glEnableVertexAttribArray(mPositionHandle);
GLES20.glVertexAttribPointer(mPositionHandle, 3, GLES20.GL_FLOAT, false, 0, mVertexBuffer);
GLES20.glDrawElements(GLES20.GL_TRIANGLE_STRIP, 4, GLES20.GL_UNSIGNED_SHORT, mIndexBuffer);
and finally the fragment shader looks like this (only relevant portion of code):
uniform sampler2D normalMap, shadowMap;
varying vec2 pos;
void main() {
vec4 color = texture2D(normalMap, pos);
vec4 shadow = texture2D(shadowMap, pos);
// do stuff with the colors
...
gl_FragColor = ...;
}
This way i was finally able to access both textures !
Hope this helps.