私は現在、OreillyのiOS向け3Dプログラミングの本を読み、後の最適化や関数とAPIの深い理解など、さまざまな目的でC++からObjective-Cにすべてを変換しています。私はむしろ、新しいGLKitを活用することを学びたいと思っています。むしろ、iOS開発のためにC++の現在の言語に依存しています。以下は、本が提供する3Dコーンモデルを作成するために私がこれまでに持っている翻訳されたコードです。残念ながら、下部のディスクとコーン自体の両方のスライバーが1つしか表示されないため、理由がわかりません。誰かがこれで私を助けることができるでしょうか。最適化（まだ翻訳中なのでまだ行っていません）や、フィードバックを聞きたいと思う何かを行うためのより良い方法の提案があれば、どうぞ。しかし、私は本当に問題を見つけるのに助けが欲しいです。私' 結果なしで数日探していました。以下に添付されているのは、私が出力しているものの画像です（完全な3Dの丸い円錐である必要があります）。
//
// IRenderingEngine2.m
// HelloArrow
//
// Created by TheGamingArt on 3/4/13.
// Copyright (c) 2013 Brandon Levasseur. All rights reserved.
//
#import "IRenderingEngine2.h"
#define STRINGIFY(A) #A
#import "Simple.frag"
#import "Simple.vert"
static const float RevolutionsPerSecond = 1;
static const float AnimationDuration = 0.25f;
static const float coneSlices = 40.f;
static const int numberOfConeVerticies = ((coneSlices/*number of coneSlices*/ +1) *2);
static const int numberOfDiskVerticies = (coneSlices + 2);
typedef struct{
GLKVector3 Position;
GLKVector4 Color;
}Vertex;
typedef struct{
GLKQuaternion Start; //starting orientation
GLKQuaternion End; //ending orientation
GLKQuaternion Current; //current interpolated orientation
float Elapsed; //time span in seconds for a slerp fraction between 0 and 1
float Duration; //time span in seconds for a slerp fraction between 0 and 1
}Animation; //enables smooth 3D transitions
@interface IRenderingEngine2(){
GLuint framebuffer;
GLuint colorRenderbuffer;
GLuint depthRenderbuffer; //Because of this being 3D, need depthRender. If only 2d, only need colorRender
float currentAngle; //angles in degrees
float desiredAngle; //added for smooth rotation transition
Vertex cone[numberOfConeVerticies];
Vertex disk[numberOfDiskVerticies];
Animation animation;
GLuint simpleProgram;
}
-(float) getRotationDirection;
-(void)applyRotation:(float)degrees;
-(GLuint)buildProgramWithVertex:(const char *)vShaderSource andFragment:(const char *)fShaderSource;
-(void)applyOrthoWithMaxX:(float)maxX andMaxY:(float)maxY;
-(GLuint)buildShaderWithSource:(const char *)source shaderType:(GLenum)type;
-(GLKQuaternion) quaternionCreateFromVectors:(GLKVector3)v0 :(GLKVector3)v1;
@end
@implementation IRenderingEngine2
-(id)init{
self = [super init];
if (self) {
glGenRenderbuffers(1, &colorRenderbuffer);
glBindRenderbuffer(GL_RENDERBUFFER, colorRenderbuffer);
}
return self;
}
-(void)setRenderWidth:(int)width andHeight:(int)height{
const float coneRadius = 0.5f;
const float coneHeight = 1.866f;
// const int coneSlices = 40;
{
//Generate vertices for the disk....
//Uses triangle fan so the total number of vertices is n+2: one exxtra vertex for the center and another for closing the loop
//Allocate space for the disk vertices.
//m_disk.resize(coneSlices + 2)
int vertexIterator = 0;
disk[vertexIterator].Color = GLKVector4Make(0.75f, 0.75f, 0.75f, 1.0f);
disk[vertexIterator].Position.x = 0.0f;
disk[vertexIterator].Position.y = 1.0f - coneHeight;
disk[vertexIterator].Position.z = 0.0f;
vertexIterator++;
//Initialize the rim vertices of the triangle fan
const float dtheta = M_2_PI / coneSlices;
for (float theta = 0.0f; vertexIterator != numberOfDiskVerticies; theta += dtheta) {
disk[vertexIterator].Color = GLKVector4Make(0.75f, 0.75f, 0.75f, 1.0f);
disk[vertexIterator].Position.x = coneRadius * cosf(theta);
disk[vertexIterator].Position.y = 1 - coneHeight;
disk[vertexIterator].Position.z = coneRadius * sinf(theta);
vertexIterator++;
}
}
{
//Generate vertices for body of cone
int vertexIterator = 0;
//Initialize the vertices of the triangle strip.
const float dtheta = M_2_PI /coneSlices;
for (float theta = 0; vertexIterator != numberOfConeVerticies ; theta += dtheta) {
//Grayscale gradient
float brightness = abs(sinf(theta)); // creates a grayscale gradient as a cheap way to simulate lighting.. aka baked lighting hack
GLKVector4 color = GLKVector4Make(brightness, brightness, brightness, 1);
//Apex vertex
cone[vertexIterator].Position = GLKVector3Make(0.0f, 1.0f, 0.0f);
cone[vertexIterator].Color = color;
vertexIterator++;
//Rim vertex
cone[vertexIterator].Position.x = coneRadius * cosf(theta);
cone[vertexIterator].Position.y = 1 - coneHeight;
cone[vertexIterator].Position.z = coneRadius * sinf(theta);
cone[vertexIterator].Color = color;
vertexIterator++;
}
}
//Create the depth buffer
glGenRenderbuffers(1, &depthRenderbuffer);
glBindRenderbuffer(GL_RENDERBUFFER, depthRenderbuffer);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT16, width * [[UIScreen mainScreen] scale], height * [[UIScreen mainScreen] scale]);
//Create the framebuffer object and attach the color buffer.
glGenFramebuffers(1, &framebuffer);
glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, colorRenderbuffer);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthRenderbuffer);
//Bind the color buffer for rendering
glBindRenderbuffer(GL_RENDERBUFFER, colorRenderbuffer);
glViewport(0, 0, width * [[UIScreen mainScreen] scale], height * [[UIScreen mainScreen] scale]);
glEnable(GL_DEPTH_TEST);
simpleProgram = [self buildProgramWithVertex:SimpleVertexShader andFragment:SimpleFragmentShader];
glUseProgram(simpleProgram);
//Set the Projection Matrix
GLint projectionUniform = glGetUniformLocation(simpleProgram, "Projection");
GLKMatrix4 projectionMatrix = GLKMatrix4MakeFrustum(-1.6f, 1.6f, -2.4f, 2.4f, 5.0f, 10.0f);
glUniformMatrix4fv(projectionUniform, 1.0f, 0.0f, &projectionMatrix.m00);
}
-(void)render{
GLuint positionSlot = glGetAttribLocation(simpleProgram, "Position");
GLuint colorSlot = glGetAttribLocation(simpleProgram, "SourceColor");
glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glEnableVertexAttribArray(positionSlot);
glEnableVertexAttribArray(colorSlot);
// animation.Current.w = 1.0f;
// animation.End.w = 1.0f;
// animation.Start.w = 1.0f;
GLKMatrix4 rotation = GLKMatrix4MakeWithQuaternion(animation.Current);
//Set the model-view matrix
GLint modelviewUniform = glGetUniformLocation(simpleProgram, "Modelview");
GLKMatrix4 modelviewMatrix = GLKMatrix4Translate(rotation, 0.0f, 0.0f, -7.0f);
glUniformMatrix4fv(modelviewUniform, 1.0f, 0.0f, &modelviewMatrix.m00);
//Draw the cone
{
GLsizei stride = sizeof(Vertex);
const GLvoid *pCoords = &cone[0].Position.x;
const GLvoid *pColors = &cone[0].Color.r; //changed here to r from x for Red
glVertexAttribPointer(positionSlot, 3, GL_FLOAT, GL_FALSE, stride, pCoords);
glVertexAttribPointer(colorSlot, 4, GL_FLOAT, GL_FALSE, stride, pColors);
glDrawArrays(GL_TRIANGLE_STRIP, 0, sizeof(cone)/sizeof(Vertex));
}
//Draw the disk that caps off the base of the cone
{
GLsizei stride = sizeof(Vertex);
const GLvoid *pCoords = &disk[0].Position.x;
const GLvoid *pColors = &disk[0].Color.r; //changed from x to r
glVertexAttribPointer(positionSlot, 3, GL_FLOAT, GL_FALSE, stride, pCoords);
glVertexAttribPointer(colorSlot, 4, GL_FLOAT, GL_FALSE, stride, pColors);
glDrawArrays(GL_TRIANGLE_FAN, 0, sizeof(disk)/sizeof(Vertex));
}
glDisableVertexAttribArray(positionSlot);
glDisableVertexAttribArray(colorSlot);
}
-(void)updateAnimationForTime:(float)timeStep{
NSString *currentQuaternion = NSStringFromGLKQuaternion(animation.Current);
NSString *endQuaternion = NSStringFromGLKQuaternion(animation.End);
if ([currentQuaternion isEqualToString:endQuaternion]) {
return;
}
animation.Elapsed += timeStep;
if (animation.Elapsed >= AnimationDuration) {
animation.Current = animation.End;
}
else{
float mu = animation.Elapsed / AnimationDuration;
animation.Current = GLKQuaternionSlerp(animation.Start, animation.End, mu);
}
}
-(void)onRotate:(enum DeviceOrientation) orientation{
GLKVector3 direction;
switch (orientation) {
case DeviceOrientationUnknown:
case DeviceOrientationPortrait:
direction = GLKVector3Make(0.0f, 1.0f, 0.0f);
break;
case DeviceOrientationPortraitUpsideDown:
direction = GLKVector3Make(0.0f, -1.0f, 0.0f);
break;
case DeviceOrientationFaceDown:
direction = GLKVector3Make(0.0f, 0.0f, -1.0f);
break;
case DeviceOrientationFaceUp:
direction = GLKVector3Make(0.0f, 0.0f, 1.0f);
break;
case DeviceOrientationLandscapeLeft:
direction = GLKVector3Make(+1.0f, 0.0f, 0.0f);
break;
case DeviceOrientationLandscapeRight:
direction = GLKVector3Make(-1.0f, 0.0f, 0.0f);
break;
}
animation.Elapsed = 0;
animation.Start = animation.Current = animation.End;
// animation.End = GLKQuaternionMakeWi
GLKVector3 vector = GLKVector3Make(0.0f, 1.0f, 0.0f);
animation.End = [self quaternionCreateFromVectors:vector :direction];
// (GLKVector3Make(0.0f, 1.0f, 0.0f), direction);
}
-(float)getRotationDirection{
float delta = desiredAngle - currentAngle;
// NSLog(@"delta: %f", delta);
if (delta == 0) {
return 0;
}
bool counterclockwise = ((delta > 0 && delta <= 180) || (delta < -180));
float test = counterclockwise ? +1.0 : -1.0;
NSLog(@"Return Value: %f",test );
return counterclockwise ? +1 : -1; //problem
}
-(void)applyRotation:(float)degrees{
}
-(void)applyOrthoWithMaxX
:(float)maxX andMaxY:(float)maxY{
}
-(GLuint)buildProgramWithVertex:(const char *)vShaderSource andFragment:(const char *)fShaderSource{
GLuint vertexShader = [self buildShaderWithSource:vShaderSource shaderType:GL_VERTEX_SHADER];
GLuint fragmentShader = [self buildShaderWithSource:fShaderSource shaderType:GL_FRAGMENT_SHADER];
GLuint programHandle = glCreateProgram();
glAttachShader(programHandle, vertexShader);
glAttachShader(programHandle, fragmentShader);
glLinkProgram(programHandle);
GLint linkSuccess;
glGetProgramiv(programHandle, GL_LINK_STATUS, &linkSuccess);
if (linkSuccess == GL_FALSE) {
GLchar messages[256];
glGetProgramInfoLog(programHandle, sizeof(messages), 0, &messages[0]);
NSLog(@"%s", messages);
exit(1);
}
return programHandle;
}
-(GLuint)buildShaderWithSource:(const char *)source shaderType:(GLenum)type{
GLuint shaderHandle = glCreateShader(type);
glShaderSource(shaderHandle, 1, &source, 0);
glCompileShader(shaderHandle);
GLint compileSuccess;
glGetShaderiv(shaderHandle, GL_COMPILE_STATUS, &compileSuccess);
if (compileSuccess == GL_FALSE) {
GLchar messages[256];
glGetShaderInfoLog(shaderHandle, sizeof(messages), 0, &messages[0]);
NSLog(@"%s", messages);
exit(1);
}
return shaderHandle;
}
-(GLKQuaternion) createFromAxis:(GLKVector3)axis withAngle:(float)radians //Minor calculating issues
{
GLKQuaternion q;
q.w = cosf(radians / 2);
q.x = q.y = q.z = sinf(radians / 2);
q.x *= axis.x;
q.y *= axis.y;
q.z *= axis.z;
return q;
}
-(GLKQuaternion) quaternionCreateFromVectors:(GLKVector3)v0 :(GLKVector3)v1 // Minor calculating issues
{
GLKVector3 v1Negative = GLKVector3Negate(v1);
NSLog(@"strings: v0: %@ v1:%@", NSStringFromGLKVector3(v0), NSStringFromGLKVector3(v1Negative));
if (/*NSStringFromGLKVector3(v0) == NSStringFromGLKVector3(v1Negative)*/ v0.g == v1Negative.g)
return [self createFromAxis:GLKVector3Make(1.0f, 0.0f, 0.0f) withAngle:M_1_PI];
GLKVector3 c = GLKVector3CrossProduct(v0, v1);// v0.Cross(v1);
int d = GLKVector3DotProduct(v0, v1); // v0.Dot(v1);
int s = sqrt((1 + d) *2);
GLKQuaternion q;
q.x = c.x / s;
q.y = c.y / s;
q.z = c.z / s;
q.w = s / 2.0f;
return q;
}
@end
ほとんどの場合、これを実行してから、GLKQuanternionsを実装して次のようなメソッドを追加する方法を学ぶ必要があります。
m_animation.End = Quaternion::CreateFromVectors(vec3(0, 1, 0), direction);
AKA：
inline QuaternionT<T> QuaternionT<T>::CreateFromVectors(const Vector3<T>& v0, const Vector3<T>& v1)
{
if (v0 == -v1)
return QuaternionT<T>::CreateFromAxisAngle(vec3(1, 0, 0), Pi);
Vector3<T> c = v0.Cross(v1);
T d = v0.Dot(v1);
T s = std::sqrt((1 + d) * 2);
QuaternionT<T> q;
q.x = c.x / s;
q.y = c.y / s;
q.z = c.z / s;
q.w = s / 2.0f;
return q;
}
一時的なアドインとして、Objective-Cのクォータニオンに対して同じメソッドを作成しました
-(GLKQuaternion) createFromAxis:(GLKVector3)axis withAngle:(float)radians //Minor calculating issues
{
GLKQuaternion q;
q.w = cosf(radians / 2);
q.x = q.y = q.z = sinf(radians / 2);
q.x *= axis.x;
q.y *= axis.y;
q.z *= axis.z;
return q;
}
-(GLKQuaternion) quaternionCreateFromVectors:(GLKVector3)v0 :(GLKVector3)v1 // Minor calculating issues
{
GLKVector3 v1Negative = GLKVector3Negate(v1);
NSLog(@"strings: v0: %@ v1:%@", NSStringFromGLKVector3(v0), NSStringFromGLKVector3(v1Negative));
if (/*NSStringFromGLKVector3(v0) == NSStringFromGLKVector3(v1Negative)*/ v0.g == v1Negative.g)
return [self createFromAxis:GLKVector3Make(1.0f, 0.0f, 0.0f) withAngle:M_1_PI];
GLKVector3 c = GLKVector3CrossProduct(v0, v1);// v0.Cross(v1);
int d = GLKVector3DotProduct(v0, v1); // v0.Dot(v1);
int s = sqrt((1 + d) *2);
GLKQuaternion q;
q.x = c.x / s;
q.y = c.y / s;
q.z = c.z / s;
q.w = s / 2.0f;
return q;
}