summaryrefslogtreecommitdiff
path: root/ui/sceneRenderer.cpp
blob: dc8e440ea2a8754528b4ead228caa687848381e5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
#include "sceneRenderer.h"
#include "maths.h"
#include <gfx/gl/shaders/fs-directionalLight.h>
#include <gfx/gl/shaders/fs-lightingShader.h>
#include <gfx/gl/shaders/vs-lightingShader.h>
#include <glm/gtc/type_ptr.hpp>

static constexpr std::array<glm::vec4, 4> displayVAOdata {{
		// positions(x,y) texture coords(z,w)
		{-1.0f, 1.0f, 0.0f, 1.0f},
		{-1.0f, -1.0f, 0.0f, 0.0f},
		{1.0f, 1.0f, 1.0f, 1.0f},
		{1.0f, -1.0f, 1.0f, 0.0f},
}};
SceneRenderer::SceneRenderer(glm::ivec2 s, GLuint o) :
	camera {{-1250.0F, -1250.0F, 35.0F}, quarter_pi, ratio(s), 0.1F, 10000.0F}, size {s}, output {o},
	lighting {lightingShader_vs, lightingShader_fs}
{
	shader.setViewPort({0, 0, size.x, size.y});
	glBindVertexArray(displayVAO);
	glBindBuffer(GL_ARRAY_BUFFER, displayVBO);
	glBufferData(GL_ARRAY_BUFFER, sizeof(displayVAOdata), nullptr, GL_STATIC_DRAW);
	glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(displayVAOdata), glm::value_ptr(displayVAOdata.front()));
	glEnableVertexAttribArray(0);
	glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, sizeof(glm::vec4), nullptr);

	glBindFramebuffer(GL_FRAMEBUFFER, gBuffer);
	const auto configuregdata
			= [this](const GLuint data, const GLint format, const GLenum type, const GLenum attachment) {
				  glBindTexture(GL_TEXTURE_2D, data);
				  glTexImage2D(GL_TEXTURE_2D, 0, format, size.x, size.y, 0, GL_RGBA, type, NULL);
				  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
				  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
				  glFramebufferTexture2D(GL_FRAMEBUFFER, attachment, GL_TEXTURE_2D, data, 0);
			  };
	configuregdata(gPosition, GL_RGBA16F, GL_FLOAT, GL_COLOR_ATTACHMENT0);
	configuregdata(gNormal, GL_RGBA16F, GL_FLOAT, GL_COLOR_ATTACHMENT1);
	configuregdata(gAlbedoSpec, GL_RGBA, GL_UNSIGNED_BYTE, GL_COLOR_ATTACHMENT2);
	configuregdata(gIllumination, GL_RGBA16F, GL_FLOAT, GL_COLOR_ATTACHMENT3);

	glBindRenderbuffer(GL_RENDERBUFFER, depth);
	glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, size.x, size.y);
	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depth);

	// finally check if framebuffer is complete
	if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
		throw std::runtime_error("Framebuffer not complete!");
	}
	glBindFramebuffer(GL_FRAMEBUFFER, output);
}

void
SceneRenderer::render(const SceneProvider & scene) const
{
	shader.setViewProjection(camera.GetViewProjection());
	glViewport(0, 0, size.x, size.y);

	// Geometry pass
	glBindFramebuffer(GL_FRAMEBUFFER, gBuffer);
	static constexpr std::array<unsigned int, 3> attachments {
			GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1, GL_COLOR_ATTACHMENT2};
	glDrawBuffers(attachments.size(), attachments.data());
	glEnable(GL_BLEND);
	glEnable(GL_CULL_FACE);
	glCullFace(GL_BACK);
	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
	glEnable(GL_DEPTH_TEST);
	glClearColor(0, 0, 0, 1);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	scene.content(shader);

	// Illumination pass
	glDrawBuffer(GL_COLOR_ATTACHMENT3);
	glDisable(GL_DEPTH_TEST);
	glEnable(GL_BLEND);
	glBlendFunc(GL_ONE, GL_ONE);
	glActiveTexture(GL_TEXTURE0);
	glBindTexture(GL_TEXTURE_2D, gPosition);
	glActiveTexture(GL_TEXTURE1);
	glBindTexture(GL_TEXTURE_2D, gNormal);
	scene.environment(shader, *this);

	// Lighting pass
	glBindFramebuffer(GL_FRAMEBUFFER, output);
	glDisable(GL_BLEND);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glActiveTexture(GL_TEXTURE0);
	glBindTexture(GL_TEXTURE_2D, gPosition);
	glActiveTexture(GL_TEXTURE1);
	glBindTexture(GL_TEXTURE_2D, gNormal);
	glActiveTexture(GL_TEXTURE2);
	glBindTexture(GL_TEXTURE_2D, gAlbedoSpec);
	glActiveTexture(GL_TEXTURE3);
	glBindTexture(GL_TEXTURE_2D, gIllumination);
	lighting.use();
	glBindVertexArray(displayVAO);
	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
	glBindVertexArray(0);
}

void
SceneRenderer::setAmbientLight(const glm::vec3 & colour) const
{
	glClearColor(colour.r, colour.g, colour.b, 1.0F);
	glClear(GL_COLOR_BUFFER_BIT);
}

void
SceneRenderer::setDirectionalLight(const glm::vec3 & colour, const glm::vec3 & direction) const
{
	if (colour.r > 0 || colour.g > 0 || colour.b > 0) {
		dirLight.use();
		dirLight.setDirectionalLight(colour, direction);
		glBindVertexArray(displayVAO);
		glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
		glBindVertexArray(0);
	}
}

SceneRenderer::DirectionalLightProgram::DirectionalLightProgram() :
	Program {lightingShader_vs, directionalLight_fs}, directionLoc {*this, "lightDirection"}, colourLoc {*this,
																									  "lightColour"}
{
}

void
SceneRenderer::DirectionalLightProgram::setDirectionalLight(const glm::vec3 & c, const glm::vec3 & d) const
{
	glUniform3fv(colourLoc, 1, glm::value_ptr(c));
	const auto nd = glm::normalize(d);
	glUniform3fv(directionLoc, 1, glm::value_ptr(nd));
}

void
SceneRenderer::SceneProvider::environment(const SceneShader &, const SceneRenderer & renderer) const
{
	renderer.setAmbientLight({0.5F, 0.5F, 0.5F});
	renderer.setDirectionalLight({0.6F, 0.6F, 0.6F}, {1, 0, -1});
}