reactphysics3d/testbed/nanogui/include/nanogui/glutil.h

347 lines
13 KiB
C++

/*
nanogui/glutil.h -- Convenience classes for accessing OpenGL >= 3.x
NanoGUI was developed by Wenzel Jakob <wenzel@inf.ethz.ch>.
The widget drawing code is based on the NanoVG demo application
by Mikko Mononen.
All rights reserved. Use of this source code is governed by a
BSD-style license that can be found in the LICENSE.txt file.
*/
#pragma once
#include <nanogui/opengl.h>
#include <Eigen/Geometry>
#include <map>
namespace half_float { class half; }
NAMESPACE_BEGIN(nanogui)
NAMESPACE_BEGIN(detail)
template <typename T> struct type_traits;
template <> struct type_traits<uint32_t> { enum { type = GL_UNSIGNED_INT, integral = 1 }; };
template <> struct type_traits<int32_t> { enum { type = GL_INT, integral = 1 }; };
template <> struct type_traits<uint16_t> { enum { type = GL_UNSIGNED_SHORT, integral = 1 }; };
template <> struct type_traits<int16_t> { enum { type = GL_SHORT, integral = 1 }; };
template <> struct type_traits<uint8_t> { enum { type = GL_UNSIGNED_BYTE, integral = 1 }; };
template <> struct type_traits<int8_t> { enum { type = GL_BYTE, integral = 1 }; };
template <> struct type_traits<double> { enum { type = GL_DOUBLE, integral = 0 }; };
template <> struct type_traits<float> { enum { type = GL_FLOAT, integral = 0 }; };
template <> struct type_traits<half_float::half> { enum { type = GL_HALF_FLOAT, integral = 0 }; };
template <typename T> struct serialization_helper;
NAMESPACE_END(detail)
using Eigen::Quaternionf;
/**
* Helper class for compiling and linking OpenGL shaders and uploading
* associated vertex and index buffers from Eigen matrices
*/
class NANOGUI_EXPORT GLShader {
template <typename T> friend struct detail::serialization_helper;
public:
/// Create an unitialized OpenGL shader
GLShader()
: mVertexShader(0), mFragmentShader(0), mGeometryShader(0),
mProgramShader(0), mVertexArrayObject(0) { }
/// Initialize the shader using the specified source strings
bool init(const std::string &name, const std::string &vertex_str,
const std::string &fragment_str,
const std::string &geometry_str = "");
/// Initialize the shader using the specified files on disk
bool initFromFiles(const std::string &name,
const std::string &vertex_fname,
const std::string &fragment_fname,
const std::string &geometry_fname = "");
/// Return the name of the shader
const std::string &name() const { return mName; }
/// Set a preprocessor definition
void define(const std::string &key, const std::string &value) { mDefinitions[key] = value; }
/// Select this shader for subsequent draw calls
void bind();
/// Release underlying OpenGL objects
void free();
/// Return the handle of a named shader attribute (-1 if it does not exist)
GLint attrib(const std::string &name, bool warn = true) const;
/// Return the handle of a uniform attribute (-1 if it does not exist)
GLint uniform(const std::string &name, bool warn = true) const;
/// Upload an Eigen matrix as a vertex buffer object (refreshing it as needed)
template <typename Matrix> void uploadAttrib(const std::string &name, const Matrix &M, int version = -1) {
uint32_t compSize = sizeof(typename Matrix::Scalar);
GLuint glType = (GLuint) detail::type_traits<typename Matrix::Scalar>::type;
bool integral = (bool) detail::type_traits<typename Matrix::Scalar>::integral;
uploadAttrib(name, (uint32_t) M.size(), (int) M.rows(), compSize,
glType, integral, (const uint8_t *) M.data(), version);
}
/// Download a vertex buffer object into an Eigen matrix
template <typename Matrix> void downloadAttrib(const std::string &name, Matrix &M) {
uint32_t compSize = sizeof(typename Matrix::Scalar);
GLuint glType = (GLuint) detail::type_traits<typename Matrix::Scalar>::type;
auto it = mBufferObjects.find(name);
if (it == mBufferObjects.end())
throw std::runtime_error("downloadAttrib(" + mName + ", " + name + ") : buffer not found!");
const Buffer &buf = it->second;
M.resize(buf.dim, buf.size / buf.dim);
downloadAttrib(name, M.size(), M.rows(), compSize, glType, (uint8_t *) M.data());
}
/// Upload an index buffer
template <typename Matrix> void uploadIndices(const Matrix &M) {
uploadAttrib("indices", M);
}
/// Invalidate the version numbers assiciated with attribute data
void invalidateAttribs();
/// Completely free an existing attribute buffer
void freeAttrib(const std::string &name);
/// Check if an attribute was registered a given name
bool hasAttrib(const std::string &name) const {
auto it = mBufferObjects.find(name);
if (it == mBufferObjects.end())
return false;
return true;
}
/// Create a symbolic link to an attribute of another GLShader. This avoids duplicating unnecessary data
void shareAttrib(const GLShader &otherShader, const std::string &name, const std::string &as = "");
/// Return the version number of a given attribute
int attribVersion(const std::string &name) const {
auto it = mBufferObjects.find(name);
if (it == mBufferObjects.end())
return -1;
return it->second.version;
}
/// Reset the version number of a given attribute
void resetAttribVersion(const std::string &name) {
auto it = mBufferObjects.find(name);
if (it != mBufferObjects.end())
it->second.version = -1;
}
/// Draw a sequence of primitives
void drawArray(int type, uint32_t offset, uint32_t count);
/// Draw a sequence of primitives using a previously uploaded index buffer
void drawIndexed(int type, uint32_t offset, uint32_t count);
/// Initialize a uniform parameter with a 4x4 matrix
void setUniform(const std::string &name, const Matrix4f &mat, bool warn = true) {
glUniformMatrix4fv(uniform(name, warn), 1, GL_FALSE, mat.data());
}
/// Initialize a uniform parameter with an integer value
void setUniform(const std::string &name, int value, bool warn = true) {
glUniform1i(uniform(name, warn), value);
}
/// Initialize a uniform parameter with a float value
void setUniform(const std::string &name, float value, bool warn = true) {
glUniform1f(uniform(name, warn), value);
}
/// Initialize a uniform parameter with a 2D vector
void setUniform(const std::string &name, const Vector2f &v, bool warn = true) {
glUniform2f(uniform(name, warn), v.x(), v.y());
}
/// Initialize a uniform parameter with a 3D vector
void setUniform(const std::string &name, const Vector3f &v, bool warn = true) {
glUniform3f(uniform(name, warn), v.x(), v.y(), v.z());
}
/// Initialize a uniform parameter with a 4D vector
void setUniform(const std::string &name, const Vector4f &v, bool warn = true) {
glUniform4f(uniform(name, warn), v.x(), v.y(), v.z(), v.w());
}
/// Return the size of all registered buffers in bytes
size_t bufferSize() const {
size_t size = 0;
for (auto const &buf : mBufferObjects)
size += buf.second.size;
return size;
}
protected:
void uploadAttrib(const std::string &name, uint32_t size, int dim,
uint32_t compSize, GLuint glType, bool integral,
const uint8_t *data, int version = -1);
void downloadAttrib(const std::string &name, uint32_t size, int dim,
uint32_t compSize, GLuint glType, uint8_t *data);
protected:
struct Buffer {
GLuint id;
GLuint glType;
GLuint dim;
GLuint compSize;
GLuint size;
int version;
};
std::string mName;
GLuint mVertexShader;
GLuint mFragmentShader;
GLuint mGeometryShader;
GLuint mProgramShader;
GLuint mVertexArrayObject;
std::map<std::string, Buffer> mBufferObjects;
std::map<std::string, std::string> mDefinitions;
};
/// Helper class for creating framebuffer objects
class NANOGUI_EXPORT GLFramebuffer {
public:
GLFramebuffer() : mFramebuffer(0), mDepth(0), mColor(0), mSamples(0) { }
/// Create a new framebuffer with the specified size and number of MSAA samples
void init(const Vector2i &size, int nSamples);
/// Release all associated resources
void free();
/// Bind the framebuffer object
void bind();
/// Release/unbind the framebuffer object
void release();
/// Blit the framebuffer object onto the screen
void blit();
/// Return whether or not the framebuffer object has been initialized
bool ready() { return mFramebuffer != 0; }
/// Return the number of MSAA samples
int samples() const { return mSamples; }
/// Quick and dirty method to write a TGA (32bpp RGBA) file of the framebuffer contents for debugging
void downloadTGA(const std::string &filename);
protected:
GLuint mFramebuffer, mDepth, mColor;
Vector2i mSize;
int mSamples;
};
/// Arcball helper class to interactively rotate objects on-screen
struct Arcball {
Arcball(float speedFactor = 2.0f)
: mActive(false), mLastPos(Vector2i::Zero()), mSize(Vector2i::Zero()),
mQuat(Quaternionf::Identity()),
mIncr(Quaternionf::Identity()),
mSpeedFactor(speedFactor) { }
Arcball(const Quaternionf &quat)
: mActive(false), mLastPos(Vector2i::Zero()), mSize(Vector2i::Zero()),
mQuat(quat),
mIncr(Quaternionf::Identity()),
mSpeedFactor(2.0f) { }
Quaternionf &state() { return mQuat; }
void setState(const Quaternionf &state) {
mActive = false;
mLastPos = Vector2i::Zero();
mQuat = state;
mIncr = Quaternionf::Identity();
}
void setSize(Vector2i size) { mSize = size; }
const Vector2i &size() const { return mSize; }
void setSpeedFactor(float speedFactor) { mSpeedFactor = speedFactor; }
float speedFactor() const { return mSpeedFactor; }
bool active() const { return mActive; }
void button(Vector2i pos, bool pressed) {
mActive = pressed;
mLastPos = pos;
if (!mActive)
mQuat = (mIncr * mQuat).normalized();
mIncr = Quaternionf::Identity();
}
bool motion(Vector2i pos) {
if (!mActive)
return false;
/* Based on the rotation controller form AntTweakBar */
float invMinDim = 1.0f / mSize.minCoeff();
float w = (float) mSize.x(), h = (float) mSize.y();
float ox = (mSpeedFactor * (2*mLastPos.x() - w) + w) - w - 1.0f;
float tx = (mSpeedFactor * (2*pos.x() - w) + w) - w - 1.0f;
float oy = (mSpeedFactor * (h - 2*mLastPos.y()) + h) - h - 1.0f;
float ty = (mSpeedFactor * (h - 2*pos.y()) + h) - h - 1.0f;
ox *= invMinDim; oy *= invMinDim;
tx *= invMinDim; ty *= invMinDim;
Vector3f v0(ox, oy, 1.0f), v1(tx, ty, 1.0f);
if (v0.squaredNorm() > 1e-4f && v1.squaredNorm() > 1e-4f) {
v0.normalize(); v1.normalize();
Vector3f axis = v0.cross(v1);
float sa = std::sqrt(axis.dot(axis)),
ca = v0.dot(v1),
angle = std::atan2(sa, ca);
if (tx*tx + ty*ty > 1.0f)
angle *= 1.0f + 0.2f * (std::sqrt(tx*tx + ty*ty) - 1.0f);
mIncr = Eigen::AngleAxisf(angle, axis.normalized());
if (!std::isfinite(mIncr.norm()))
mIncr = Quaternionf::Identity();
}
return true;
}
Matrix4f matrix() const {
Matrix4f result2 = Matrix4f::Identity();
result2.block<3,3>(0, 0) = (mIncr * mQuat).toRotationMatrix();
return result2;
}
protected:
bool mActive;
Vector2i mLastPos;
Vector2i mSize;
Quaternionf mQuat, mIncr;
float mSpeedFactor;
};
extern NANOGUI_EXPORT Vector3f project(const Vector3f &obj, const Matrix4f &model,
const Matrix4f &proj, const Vector2i &viewportSize);
extern NANOGUI_EXPORT Vector3f unproject(const Vector3f &win, const Matrix4f &model,
const Matrix4f &proj, const Vector2i &viewportSize);
extern NANOGUI_EXPORT Matrix4f lookAt(const Vector3f &eye, const Vector3f &center,
const Vector3f &up);
extern NANOGUI_EXPORT Matrix4f ortho(const float left, const float right, const float bottom,
const float top, const float zNear, const float zFar);
extern NANOGUI_EXPORT Matrix4f frustum(const float left, const float right, const float bottom,
const float top, const float nearVal,
const float farVal);
extern NANOGUI_EXPORT Matrix4f scale(const Matrix4f &m, const Vector3f &v);
extern NANOGUI_EXPORT Matrix4f translate(const Matrix4f &m, const Vector3f &v);
NAMESPACE_END(nanogui)