opengl-playground/src/textured-rectangle.cpp

102 lines
2.6 KiB
C++

#include <opengl-playground/textured-rectangle.hpp>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
TexturedRectangle::TexturedRectangle(float x0, float y0, float x1, float y1, std::shared_ptr<OpenGlShaderProgram> &shaderprog,
std::shared_ptr<OpenGlTexture> &texture) :
OpenGlGraphics(shaderprog)
{
this->pos1[0] = x0;
this->pos1[1] = y0;
this->pos2[0] = x1;
this->pos2[1] = y1;
this->setZoom(1.0f);
this->setOffset(0.0f, 0.0f);
this->vao = 0;
this->base_color = glm::vec4(1.0f, 0.0f, 0.0f, 1.0f);
this->m_texture = texture;
}
void TexturedRectangle::realize()
{
GLuint vbo;
GLuint elem_buff;
const unsigned int indices[] = {
0, 1, 2,
2, 0, 3
};
float vertices[16] = {
this->pos1[0], this->pos1[1], 0.0f, 0.0f,
this->pos1[0], this->pos2[1], 0.0f, 1.0f,
this->pos2[0], this->pos2[1], 1.0f, 1.0f,
this->pos2[0], this->pos1[1], 1.0f, 0.0f,
};
glGenVertexArrays(1, &this->vao);
glBindVertexArray(this->vao);
glGenBuffers(1, &vbo);
glBindBuffer(GL_ARRAY_BUFFER, vbo);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
glGenBuffers(1, &elem_buff);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, elem_buff);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(float), (void*)0);
glEnableVertexAttribArray(0);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(float), (void*)(2*sizeof(float)));
glEnableVertexAttribArray(1);
}
void TexturedRectangle::render()
{
this->shaderprog->use();
this->shaderprog->setUniformVec4("base_color", this->base_color);
this->shaderprog->setUniformMat4("model_matrix", this->model_matrix);
this->shaderprog->setUniformInt("uni_texture", 0);
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
this->m_texture->use(0UL);
glBindVertexArray(this->vao);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
}
void TexturedRectangle::setZoom(float zoom)
{
this->zoom = zoom;
this->calculateModelMatrix();
}
float TexturedRectangle::getZoom()
{
return this->zoom;
}
void TexturedRectangle::setOffset(float x_off, float y_off)
{
this->x_offset = x_off;
this->y_offset = y_off;
this->calculateModelMatrix();
}
float TexturedRectangle::getOffsetX()
{
return this->x_offset;
}
float TexturedRectangle::getOffsetY()
{
return this->y_offset;
}
void TexturedRectangle::setBaseColor(const glm::vec4 &color)
{
this->base_color = color;
}
void TexturedRectangle::calculateModelMatrix()
{
glm::mat4 moved_matrix = glm::translate(glm::mat4(1.0f), glm::vec3(-this->x_offset, -this->y_offset, 0.0f));
this->model_matrix = glm::scale(moved_matrix, glm::vec3(this->zoom, this->zoom, 0.0f));
}