init

assets/shader/deferred/deferred.fs

@@ -0,0 +1,27 @@
+#version 460 core
+
+layout (location = 0) in vec3 _pos;
+layout (location = 1) in vec3 _norm;
+layout (location = 2) in vec2 _tex;
+layout (location = 3) in uint _id;
+
+layout (std140) uniform matrices
+{
+  mat4 projection;
+  mat4 camera;
+}
+
+uniform mat4 model;
+
+out vec3 pos;
+out vec3 norm;
+out vec2 tex;
+out vec2 id;
+
+void main() {
+  gl_Position = projection * camera * model * vec4(_pos, 1.0);
+  pos = vec3(model * vec4(_pos, 1.0));
+  norm = _norm;
+  tex = _tex;
+  id = _id;
+}

assets/shader/deferred/deferred.vs

@@ -0,0 +1,32 @@
+#version 460
+
+struct material_t {
+  sampler2D albedo;
+  sampler2D normal;
+  sampler2D specular;
+  sampler2D rougness;
+  sampler2D metalic;
+};
+
+layout (std140) buffer material_buffer {
+  material_t materials[];
+};
+
+in vec3 pos;
+in vec3 norm;
+in vec2 tex;
+in uint id;
+
+out vec3 position;
+out vec3 albedo;
+out vec3 normal;
+out vec3 material;
+
+void main() {
+  position = pos;
+  albedo = texture(materials[id].albedo, tex).rgb;
+  normal = texture(materials[id].normal, tex).rgb;
+  material.x = texture(materials[id].specular, tex).x;
+  material.y = texture(materials[id].rougness, tex).y;
+  material.z = texture(materials[id].metalic, tex).z;
+}

go.mod

@@ -0,0 +1,9 @@
+module git.tek.govt.hu/dowerx/opengl-deferred
+
+go 1.23.0
+
+require (
+	github.com/go-gl/gl v0.0.0-20231021071112-07e5d0ea2e71 // indirect
+	github.com/go-gl/glfw/v3.3/glfw v0.0.0-20240506104042-037f3cc74f2a // indirect
+	github.com/go-gl/mathgl v1.1.0 // indirect
+)

go.sum

@@ -0,0 +1,8 @@
+github.com/go-gl/gl v0.0.0-20231021071112-07e5d0ea2e71 h1:5BVwOaUSBTlVZowGO6VZGw2H/zl9nrd3eCZfYV+NfQA=
+github.com/go-gl/gl v0.0.0-20231021071112-07e5d0ea2e71/go.mod h1:9YTyiznxEY1fVinfM7RvRcjRHbw2xLBJ3AAGIT0I4Nw=
+github.com/go-gl/glfw/v3.3/glfw v0.0.0-20240506104042-037f3cc74f2a h1:vxnBhFDDT+xzxf1jTJKMKZw3H0swfWk9RpWbBbDK5+0=
+github.com/go-gl/glfw/v3.3/glfw v0.0.0-20240506104042-037f3cc74f2a/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
+github.com/go-gl/mathgl v1.1.0 h1:0lzZ+rntPX3/oGrDzYGdowSLC2ky8Osirvf5uAwfIEA=
+github.com/go-gl/mathgl v1.1.0/go.mod h1:yhpkQzEiH9yPyxDUGzkmgScbaBVlhC06qodikEM0ZwQ=
+golang.org/x/image v0.0.0-20190321063152-3fc05d484e9f/go.mod h1:kZ7UVZpmo3dzQBMxlp+ypCbDeSB+sBbTgSJuh5dn5js=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=

main.go

@@ -0,0 +1,62 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"git.tek.govt.hu/dowerx/opengl-deferred/types/shader"
+	"github.com/go-gl/gl/v4.6-core/gl"
+	"github.com/go-gl/glfw/v3.3/glfw"
+)
+
+const (
+	WIDTH  = 640
+	HEIGHT = 480
+	TITLE  = "opengl-deferred"
+)
+
+func main() {
+	// init glfw
+	if err := glfw.Init(); err != nil {
+		panic(err)
+	}
+	defer glfw.Terminate()
+
+	glfw.WindowHint(glfw.Resizable, glfw.False)
+	glfw.WindowHint(glfw.ContextVersionMajor, 4)
+	glfw.WindowHint(glfw.ContextVersionMinor, 6)
+	glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)
+	glfw.WindowHint(glfw.OpenGLForwardCompatible, glfw.True)
+
+	window, err := glfw.CreateWindow(WIDTH, HEIGHT, TITLE, nil, nil)
+	if err != nil {
+		panic(err)
+	}
+	window.MakeContextCurrent()
+
+	// init glow
+	if err := gl.Init(); err != nil {
+		panic(err)
+	}
+
+	fmt.Println("OpenGL version:", gl.GoStr(gl.GetString(gl.VERSION)))
+
+	// load assets
+	// shader
+	vertexSource, err := os.ReadFile("assets/shader/deferred/deferred.vs")
+	if err != nil {
+		panic(err)
+	}
+	fragmentSource, err := os.ReadFile("assets/shader/deferred/deferred.fs")
+	if err != nil {
+		panic(err)
+	}
+
+	deferredShader, err := shader.New(string(vertexSource), string(fragmentSource))
+	if err != nil {
+		panic(err)
+	}
+	defer deferredShader.Delete()
+
+	deferredShader.Use()
+}

types/shader/shader.go

@@ -0,0 +1,79 @@
+package shader
+
+import (
+	"errors"
+	"strings"
+
+	"github.com/go-gl/gl/v4.6-core/gl"
+)
+
+type Shader struct {
+	program  uint32
+	uniforms map[string]uint32
+}
+
+func (s *Shader) Use() {
+	gl.UseProgram(s.program)
+}
+
+func (s *Shader) Delete() {
+	gl.DeleteProgram(s.program)
+}
+
+func compileShader(source string, shaderType uint32) (uint32, error) {
+	shader := gl.CreateShader(shaderType)
+
+	csource, free := gl.Strs(source)
+	gl.ShaderSource(shader, 1, csource, nil)
+	free()
+	gl.CompileShader(shader)
+
+	var status int32
+	gl.GetShaderiv(shader, gl.COMPILE_STATUS, &status)
+	if status == gl.FALSE {
+		var logLength int32
+		gl.GetShaderiv(shader, gl.INFO_LOG_LENGTH, &logLength)
+
+		log := strings.Repeat("\x00", int(logLength+1))
+		gl.GetShaderInfoLog(shader, logLength, nil, gl.Str(log))
+
+		return 0, errors.New(log)
+	}
+
+	return shader, nil
+}
+
+func New(vertexSource string, fragmantSource string) (shader Shader, _ error) {
+	shader.uniforms = make(map[string]uint32)
+
+	vertexShader, err := compileShader(vertexSource, gl.VERTEX_SHADER)
+	if err != nil {
+		return shader, err
+	}
+
+	fragmantShader, err := compileShader(fragmantSource, gl.FRAGMENT_SHADER)
+	if err != nil {
+		return shader, err
+	}
+
+	shader.program = gl.CreateProgram()
+	gl.AttachShader(shader.program, vertexShader)
+	gl.AttachShader(shader.program, fragmantShader)
+	gl.LinkProgram(shader.program)
+	defer gl.DeleteShader(vertexShader)
+	defer gl.DeleteShader(fragmantShader)
+
+	var status int32
+	gl.GetProgramiv(shader.program, gl.LINK_STATUS, &status)
+	if status == gl.FALSE {
+		var logLength int32
+		gl.GetProgramiv(shader.program, gl.INFO_LOG_LENGTH, &logLength)
+
+		log := strings.Repeat("\x00", int(logLength+1))
+		gl.GetProgramInfoLog(shader.program, logLength, nil, gl.Str(log))
+
+		return shader, errors.New(log)
+	}
+
+	return shader, nil
+}