live2D does not work well with Sprite3D

vantaci

I got a problem that live2d object does not work well with Sprite3D in cocos2d-x, could anyone give me some tips?

Here is the situation:
1. There is a scene with Live2D object created by lua script;
2. close this scene, enter second scene with a Sprite3D object, the Sprite3D object just gone;
3. if delete the live2d object in first scene, or just comment draw function as below
void LAppModel::draw()
{
if (live2DModel == NULL)return;

live2DModel->draw(); //comment this
}
then re-enter second scene, the Sprite3D object appears normally;

according to information generated by Sprite3D object rendering, looks like some resources or render state belong to Sprite3D was corupted, but system throws no error.

live2D version:Live2D_SDK_OpenGL_2.0.06_1_en
cocos2d-x:3.3

vantaci

Forget to mention: i defined a new render shader for Sprite3D, code as below:

const char* cc3D_PositionNormalTexOutline_vert = STRINGIFY(
attribute vec4 a_position;
attribute vec2 a_texCoord;
attribute vec3 a_normal;
varying vec2 TextureCoordOut;
varying vec3 v_normal;

void main(void)
{
vec4 ePosition = CC_MVMatrix * a_position;
v_normal = CC_NormalMatrix * a_normal;

TextureCoordOut = a_texCoord;
TextureCoordOut.y = 1.0 - TextureCoordOut.y;
gl_Position = CC_PMatrix * ePosition;
}
);
const char* cc3D_ColorNormalTexOutline_frag = STRINGIFY(

\n#ifdef GL_ES\n
varying mediump vec2 TextureCoordOut;
varying mediump vec3 v_normal;
\n#else\n

varying vec2 TextureCoordOut;
varying vec3 v_normal;

\n#endif\n
uniform vec4 u_color;

uniform float u_falloffValue;
uniform float u_powValue;
uniform vec4 u_innerColor;

void main(void)
{
vec3 normal = normalize(v_normal); // vertex normal does not calculate right here

float value = dot(normal,vec3(0.0,0.0,1.0));

vec4 texcolor = texture2D(CC_Texture0, TextureCoordOut);

vec4 finalcolor = texcolor*u_color;


value = clamp(value * u_falloffValue,0.0,1.0);

value = pow(value, u_powValue);

float inverseValue = clamp(1.0-value,0.0,1.0);
finalcolor = finalcolor*value + u_innerColor*inverseValue;
finalcolor.a = value;

gl_FragColor = finalcolor;
}
);

Imai(dev_staff)

Hi Vantaci ,
Could you please test this code?

void LAppModel::draw()
{
if (live2DModel == NULL)return;

live2DModel->draw(); //comment this
glFrontFace(GL_CCW);//change Front Face
}

In live2DModel::draw function, we call glFrontFace(GL_CW).
Unfortunately we forgot to restore this state in live2d::DrawProfileCocos2D::postDraw() .

This bug will be fixed next live2d SDK version.

vantaci

Hi Imai , thank you for the response.

glFrontFace(GL_CCW) does work, both live2d and Sprite3D show up correctly.

That's a great help.
/////////////////////////////////////////////////////////////////
Meanwhile, there's another problem:
We got a crash days before when using Spine and live2D object at the same time, the Spine crash during rendering,
then we add code like this:
void L2DSprite::onDraw(const cocos2d::Mat4 &transform, uint32_t flags)
{
Director * director = Director::getInstance();
MATRIX_STACK_TYPE type = MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW;

director->pushMatrix(type);
director->loadMatrix(type, transform);

LAppLive2DManager* Live2DMgr=LAppLive2DManager::getInstance();
Live2DMgr->onUpdate();

//buff error
glBindBuffer(GL_ARRAY_BUFFER, 0); //We have to set bound buffer to 0 here
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);//We have to set bound buffer to 0 here

director->popMatrix(type);
}
Finally, after buffer was rebound to 0, the crash gone.
I think something is wrong with buffer binding.


Thanks

taigacon

I guess you should upgrade your cocos2d-x to 3.4 and try again.
Cocos2d-x 3.4 has fixed a bug about VAO, that VAO should be bound to 0 before VBO does. Just add GL::bindVAO(0); before glBindBuffer(GL_ARRAY_BUFFER, 0); within all cocos2d-x source code.
If you enabled VAO configuration, you should apply this patch of cocos2d-x and do the samething on your code.