COSC-3P98-Final-Project/include/render/gl.h

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9.5 KiB
C++

/*
* Created by Brett on 08/02/23.
* Licensed under GNU General Public License V3.0
* See LICENSE file for license detail
*/
#ifndef FINALPROJECT_GL_H
#define FINALPROJECT_GL_H
// pulls in gl headers along with window tools
#include <render/window.h>
#include <vector>
#include <unordered_map>
#include <blt/math/math.h>
#include <blt/std/string.h>
#include <string>
namespace fp {
/**
* Supported VBO types.
*/
enum vbo_type {
ARRAY_BUFFER = GL_ARRAY_BUFFER,
ELEMENT_BUFFER = GL_ELEMENT_ARRAY_BUFFER
};
enum vbo_mem_type {
STATIC = GL_STATIC_DRAW,
STREAM = GL_STREAM_DRAW,
DYNAMIC = GL_DYNAMIC_DRAW
};
struct VBO {
GLuint vboID = 0;
int size = 0;
vbo_type type = ARRAY_BUFFER;
vbo_mem_type mem_type = STATIC;
VBO(vbo_type type, void* data, int size, vbo_mem_type mem_type = STATIC): size(size), type(type), mem_type(mem_type) {
glGenBuffers(1, &vboID);
bind();
glBufferData(type, size, data, mem_type);
}
template<typename T>
VBO(vbo_type type, std::vector<T>& data, vbo_mem_type mem_type = STATIC): type(type), mem_type(mem_type) {
glGenBuffers(1, &vboID);
bind();
size = data.size() * sizeof(float);
glBufferData(type, size, data.data(), mem_type);
//glBufferSubData(type, 0, )
}
inline void update(void* new_data, int data_size) {
bind();
// optimization technique is to not reallocate the memory on the GPU if the new buffer size is not larger than our current buffer
if (data_size <= size){
// we can do this as long as we overwrite from the beginning. Since the new draw call will only use of to size of the allocated buffer
// to do all its drawing, the extra space unused can be ignored and saved for future use.
glBufferSubData(type, 0, data_size, new_data);
} else
glBufferData(type, data_size, new_data, mem_type);
size = data_size;
glBindBuffer(type, 0);
}
template<typename T>
inline void update(std::vector<T>& new_data) {
update(new_data.data(), new_data.size() * sizeof(T));
}
template<typename T, size_t size>
inline void update(std::array<T, size>& new_data){
update(new_data.data(), size * sizeof(T));
}
inline void bind() const {
glBindBuffer(type, vboID);
}
~VBO() {
glDeleteBuffers(1, &vboID);
}
};
class VAO {
private:
GLuint vaoID = 0;
// -1 will contain indices VBO
std::unordered_map<int, VBO*> VBOs;
public:
VAO();
// we should not be copying VAOs! VAOs should be allocated on the heap!
VAO(const VAO& copy) = delete;
VAO(VAO&& move) = delete;
/**
* binds the VBO as an attribute buffer for use in a shader
* @param vbo vbo to bind
* @param attribute_number attribute position to bind
* @param coordinate_size size of this attribute (1 for float, 2 for vec2...)
* @param type type to store. Use GL_FLOAT mostly
* @param stride stride how many bytes the COMPLETE data takes in the VBO, 0 will automatically assume packed data.
* @param offset offset into the data that this attribute is stored. Allows for weaving of data
* @param repeated used to specify that this is the second+ time we've used this VBO to point to data, as a result it will be not be added
* to the attribute update list and MUST be updated using the original attribute number
*/
void bindVBO(VBO* vbo, int attribute_number, int coordinate_size, GLenum type = GL_FLOAT, int stride = 0, long offset = 0, bool repeated = false);
/**
* Binds the VBO as if it was the element buffer (indices). Note: calling this more than once is not supported.
* @param vbo vbo to use
*/
void bindElementVBO(VBO* vbo);
inline VBO* getVBO(int attribute_number) {
return VBOs[attribute_number];
}
inline void bind() const {
glBindVertexArray(vaoID);
}
~VAO();
};
class shader_base {
protected:
struct IntDefaultedToMinusOne {
GLint i = -1;
};
std::unordered_map<std::string, IntDefaultedToMinusOne> uniformVars;
GLuint programID = 0;
inline GLint getUniformLocation(const std::string &name) {
if (uniformVars[name].i != -1)
return uniformVars[name].i;
int loc = glGetUniformLocation(programID, name.c_str());
uniformVars[name].i = loc;
return loc;
}
public:
inline void bind() const {
glUseProgram(programID);
}
inline void setBool(const std::string &name, bool value) {
glUniform1i(getUniformLocation(name), (int) value);
}
inline void setInt(const std::string &name, int value) {
glUniform1i(getUniformLocation(name), value);
}
inline void setFloat(const std::string &name, float value) {
glUniform1f(getUniformLocation(name), value);
}
inline void setMatrix(const std::string &name, blt::mat4x4 &matrix) {
glUniformMatrix4fv(getUniformLocation(name), 1, GL_FALSE, matrix.ptr());
}
inline void setVec3(const std::string &name, const blt::vec3 &vec) {
glUniform3f(getUniformLocation(name), vec.x(), vec.y(), vec.z());
}
inline void setVec4(const std::string &name, const blt::vec4 &vec) {
glUniform4f(getUniformLocation(name), vec.x(), vec.y(), vec.z(), vec.w());
}
inline void setVec2(const std::string &name, float x, float y) {
glUniform2f(getUniformLocation(name), x, y);
}
inline void setVec3(const std::string &name, float x, float y, float z) {
glUniform3f(getUniformLocation(name), x, y, z);
}
inline void setVec4(const std::string &name, float x, float y, float z, float w) {
glUniform4f(getUniformLocation(name), x, y, z, w);
}
};
/**
* a basic computer shader class, contains the functions and resources required to use compute shaders!
*/
class compute_shader : public shader_base {
private:
GLuint shaderID = 0;
public:
explicit compute_shader(const std::string& shader_source, bool loadAsString = true);
inline void execute(int x, int y, int z) const {
bind();
glDispatchCompute(x, y, z);
}
~compute_shader();
};
class shader : public shader_base {
private:
GLuint vertexShaderID = 0;
GLuint fragmentShaderID = 0;
// while these will remain unused. (Webgl2 apparently doesn't support them despite being based on GL4.3? that's a TODO!)
GLuint geometryShaderID = 0;
// this would be very useful however it is highly unlikely webgl will support it
// im leaving some of this stuff in here because I might expand the native application to use some of it.
// im trying to keep the web and native versions the same though
GLuint tessellationShaderID = 0;
static unsigned int createShader(const std::string& source, int type);
public:
/**
* Creates a shader
* @param vertex vertex shader source or file
* @param fragment fragment shader source or file
* @param geometry geometry shader source or file (optional)
* @param load_as_string load the shader as a string (true) or use the string to load the shader as a file (false)
*/
shader(const std::string &vertex, const std::string &fragment, const std::string &geometry = "", bool load_as_string = true);
shader(shader&& move) noexcept;
// used to set the location of VAOs to the in variables in opengl shaders.
void bindAttribute(int attribute, const std::string &name) const;
// used to set location of shared UBOs like the perspective and view matrix
void setUniformBlockLocation(const std::string &name, int location) const;
~shader();
static void updateProjectionMatrix(const blt::mat4x4& projectionMatrix);
static void updateOrthographicMatrix(const blt::mat4x4& orthoMatrix);
static void updateViewMatrix(const blt::mat4x4& viewMatrix);
// returns the perspective view matrix which is calculated per frame. (This is for optimization)
static const blt::mat4x4& getPVM();
};
}
#endif //FINALPROJECT_GL_H