src/gl/basicshaderprogram.h

Wed, 25 May 2022 20:36:34 +0300

author
Teemu Piippo <teemu@hecknology.net>
date
Wed, 25 May 2022 20:36:34 +0300
changeset 199
6988973515d2
parent 118
8e1c9f18ae15
child 215
34c6e7bc4ee1
permissions
-rw-r--r--

Fix pick() picking from weird places on the screen with high DPI scaling

glReadPixels reads data from the frame buffer, which contains data after
high DPI scaling, so any reads to that need to take this scaling into account

#pragma once
#include "common.h"

/**
 * @brief Base class for basic shader programs
 *
 * A basic program is a collection of a single VAO with a single VBO,
 * a vertex shader and a fragment shader. This program deals with these
 * components, leaving the program-specific details to the subclasses.
 */
class AbstractBasicShaderProgram : public QObject, protected QOpenGLFunctions
{
	Q_OBJECT
public:
	AbstractBasicShaderProgram(QObject* parent = nullptr);
	~AbstractBasicShaderProgram() = default;
	void initialize();
	Q_SLOT void setViewMatrix(const glm::mat4& newViewMatrix);
	Q_SLOT void setProjectionMatrix(const glm::mat4& newProjectionMatrix);
	Q_SLOT void setModelMatrix(const glm::mat4& newModelMatrix);
	void draw();
	void teardown();
protected:
	void setMatrix(const char* name, const glm::mat4& matrix);
	void checkForGLErrors();
	/// \returns the source code of the vertex shader
	virtual const char* vertexShaderSource() const = 0;
	/// \returns the source code of the fragment shader
	virtual const char* fragmentShaderSource() const = 0;
	/// \returns the vertex data for the VBO
	virtual const void* vertexData() const = 0;
	/// \returns the size of a single vertex in bytes
	virtual int vertexSize() const = 0;
	/// \returns the amount of vertices in the data
	virtual int vertexCount() const = 0;
	/// Called during initialization to set up the VAO. Set up your vertex array attributes here.
	virtual void setupVertexArrays() = 0;
	// \returns what kind of elements are drawn (GL_QUADS, GL_TRIANGLES, GL_LINES, etc)
	virtual GLenum drawMode() const = 0;
	virtual QOpenGLBuffer::UsagePattern usagePattern() const = 0;
	bool isInitialized = false;
	QOpenGLBuffer buffer;
	QOpenGLShader vertexShader;
	QOpenGLShader fragmentShader;
	std::optional<gl::ShaderProgram> program{std::nullopt};
	QOpenGLVertexArrayObject vertexArrayObject;
};

mercurial