先上图：
cocos2dx版本是3.13.1，仿照网上教程写了个立方体，但是转起来的的时候总是缺一两个面，shader用的是cocos2dx自带的GLProgram::SHADER_NAME_POSITION_TEXTURE。
求各位老司机解惑，谢谢。
主要代码如下：
void CubeTexture::visit(cocos2d::Renderer *renderer, const Mat4 &transform, uint32_t parentFlags)
{
Layer::visit(renderer, transform, parentFlags);
_command.init(_globalZOrder);
_command.func = CC_CALLBACK_0(CubeTexture::onDraw, this);
Director::getInstance()->getRenderer()->addCommand(&_command);
}
void CubeTexture::onDraw()
{
Director::getInstance()->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
Director::getInstance()->loadIdentityMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
Director::getInstance()->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION);
Director::getInstance()->loadIdentityMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION);
Mat4 projectionMatrix;
auto size = Director::getInstance()->getWinSize();
Mat4::createPerspective(60, size.width / size.height, 1.0, 50, &projectionMatrix);
Director::getInstance()->multiplyMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION, projectionMatrix);
Mat4 modelViewMatrix;
Mat4::createLookAt(Vec3(0, 0, 1), Vec3(0, 0, 0), Vec3(0, 1, 0), &modelViewMatrix);
modelViewMatrix.translate(0, 0, -5);
static float rotation = 0;
modelViewMatrix.rotate(Vec3(1, 1, 1), CC_DEGREES_TO_RADIANS(rotation));
rotation++;
if (rotation > 360) {
rotation = 0;
}
Director::getInstance()->multiplyMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW, modelViewMatrix);
auto glProgram = getGLProgram();//GLProgram::SHADER_NAME_POSITION_TEXTURE
glProgram->use();
glProgram->setUniformsForBuiltins();
typedef struct {
float Position[3];
float TexCoord[2];
} Vertex;
Vertex data[] = {
// Front
{ { 1, -1, 0 }, { 1, 0 } },
{ { 1, 1, 0 }, { 1, 1 } },
{ { -1, 1, 0 }, { 0, 1 } },
{ { -1, -1, 0 }, { 0, 0 } },
// Back
{ { 1, 1, -2 }, { 1, 0 } },
{ { -1, -1, -2 }, { 0, 1 } },
{ { 1, -1, -2 }, { 1, 1 } },
{ { -1, 1, -2 }, { 0, 0 } },
// Left
{ { -1, -1, 0 }, { 1, 0 } },
{ { -1, 1, 0 }, { 1, 1 } },
{ { -1, 1, -2 }, { 0, 1 } },
{ { -1, -1, -2 }, { 0, 0 } },
// Right
{ { 1, -1, -2 }, { 1, 0 } },
{ { 1, 1, -2 }, { 1, 1 } },
{ { 1, 1, 0 }, { 0, 1 } },
{ { 1, -1, 0 }, { 0, 0 } },
// Top
{ { 1, 1, 0 }, { 1, 0 } },
{ { 1, 1, -2 }, { 1, 1 } },
{ { -1, 1, -2 }, { 0, 1 } },
{ { -1, 1, 0 }, { 0, 0 } },
// Bottom
{ { 1, -1, -2 }, { 1, 0 } },
{ { 1, -1, 0 }, { 1, 1 } },
{ { -1, -1, 0 }, { 0, 1 } },
{ { -1, -1, -2 }, { 0, 0 } }
};
//set data
GLuint vertexBuffer;
glGenBuffers(1, &vertexBuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(data), data, GL_STATIC_DRAW);
GLubyte indices[] = {
// Front
0, 1, 2,
2, 3, 0,
// Back
4, 5, 6,
4, 5, 7,
// Left
8, 9, 10,
10, 11, 8,
// Right
12, 13, 14,
14, 15, 12,
// Top
16, 17, 18,
18, 19, 16,
// Bottom
20, 21, 22,
22, 23, 20
};
//set indices
GLuint indexVBO;
glGenBuffers(1, &indexVBO);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexVBO);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
GLuint positionLocation = glGetAttribLocation(glProgram->getProgram(), "a_position");
glEnableVertexAttribArray(positionLocation);
glVertexAttribPointer(positionLocation,
3,
GL_FLOAT,
GL_FALSE,
sizeof(Vertex),
(GLvoid*)offsetof(Vertex, Position));
GLuint TexCoordLocation = glGetAttribLocation(glProgram->getProgram(), "a_texCoord");
glEnableVertexAttribArray(TexCoordLocation);
glVertexAttribPointer(TexCoordLocation,
2,
GL_FLOAT,
GL_FALSE,
sizeof(Vertex),
(GLvoid*)offsetof(Vertex, TexCoord));
GLuint textureId;
textureId = Director::getInstance()->getTextureCache()->addImage("1.png")->getName();
GL::bindTexture2D(textureId);
glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
glEnable(GL_BLEND);
glEnable(GL_DEPTH_TEST);
glDrawElements(GL_TRIANGLES, 36, GL_UNSIGNED_BYTE, (GLvoid*)0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
glBindVertexArray(0);
CC_INCREMENT_GL_DRAWN_BATCHES_AND_VERTICES(1, 36);
CHECK_GL_ERROR_DEBUG();
Director::getInstance()->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION);
Director::getInstance()->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
}