began large scale restructure

app/render/glfunc.cpp

@@ -0,0 +1,90 @@
+#include "glfunc.h"
+
+#include <QOpenGLFunctions>
+#include <QOpenGLVertexArrayObject>
+#include <QOpenGLBuffer>
+
+const GLfloat blit_vertices[] = {
+  -1.0f, -1.0f, 0.0f,
+  1.0f, -1.0f, 0.0f,
+  1.0f, 1.0f, 0.0f,
+
+  -1.0f, -1.0f, 0.0f,
+  -1.0f, 1.0f, 0.0f,
+  1.0f, 1.0f, 0.0f
+};
+
+const GLfloat blit_texcoords[] = {
+  0.0, 0.0,
+  1.0, 0.0,
+  1.0, 1.0,
+
+  0.0, 0.0,
+  0.0, 1.0,
+  1.0, 1.0
+};
+
+const GLfloat flipped_blit_texcoords[] = {
+  0.0, 1.0,
+  1.0, 1.0,
+  1.0, 0.0,
+
+  0.0, 1.0,
+  0.0, 0.0,
+  1.0, 0.0
+};
+
+/**
+ * @brief Set up texture mipmaps
+ * @param f
+ */
+void PrepareToDraw(QOpenGLFunctions* f) {
+  f->glGenerateMipmap(GL_TEXTURE_2D);
+  f->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+  f->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+  f->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
+  f->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
+}
+
+void olive::gl::Blit(QOpenGLShaderProgram* pipeline, bool flipped, QMatrix4x4 matrix) {
+
+  QOpenGLFunctions* func = QOpenGLContext::currentContext()->functions();
+  PrepareToDraw(func);
+
+  QOpenGLVertexArrayObject m_vao;
+  m_vao.create();
+  m_vao.bind();
+
+  QOpenGLBuffer m_vbo;
+  m_vbo.create();
+  m_vbo.bind();
+  m_vbo.allocate(blit_vertices, 18 * sizeof(GLfloat));
+  m_vbo.release();
+
+  QOpenGLBuffer m_vbo2;
+  m_vbo2.create();
+  m_vbo2.bind();
+  m_vbo2.allocate(flipped ? flipped_blit_texcoords : blit_texcoords, 12 * sizeof(GLfloat));
+  m_vbo2.release();
+
+  pipeline->bind();
+
+  pipeline->setUniformValue("mvp_matrix", matrix);
+  pipeline->setUniformValue("texture", 0);
+
+  GLuint vertex_location = pipeline->attributeLocation("a_position");
+  m_vbo.bind();
+  func->glEnableVertexAttribArray(vertex_location);
+  func->glVertexAttribPointer(vertex_location, 3, GL_FLOAT, GL_FALSE, 0, 0);
+  m_vbo.release();
+
+  GLuint tex_location = pipeline->attributeLocation("a_texcoord");
+  m_vbo2.bind();
+  func->glEnableVertexAttribArray(tex_location);
+  func->glVertexAttribPointer(tex_location, 2, GL_FLOAT, GL_FALSE, 0, 0);
+  m_vbo2.release();
+
+  func->glDrawArrays(GL_TRIANGLES, 0, 6);
+
+  pipeline->release();
+}