dagon.render.passes.forward source code

1 /*
2 Copyright (c) 2020-2022 Timur Gafarov
3 
4 Boost Software License - Version 1.0 - August 17th, 2003
5 Permission is hereby granted, free of charge, to any person or organization
6 obtaining a copy of the software and accompanying documentation covered by
7 this license (the "Software") to use, reproduce, display, distribute,
8 execute, and transmit the Software, and to prepare derivative works of the
9 Software, and to permit third-parties to whom the Software is furnished to
10 do so, all subject to the following:
11 
12 The copyright notices in the Software and this entire statement, including
13 the above license grant, this restriction and the following disclaimer,
14 must be included in all copies of the Software, in whole or in part, and
15 all derivative works of the Software, unless such copies or derivative
16 works are solely in the form of machine-executable object code generated by
17 a source language processor.
18 
19 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
22 SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
23 FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
24 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
25 DEALINGS IN THE SOFTWARE.
26 */
27 
28 module dagon.render.passes.forward;
29 
30 import std.stdio;
31 
32 import dlib.core.memory;
33 import dlib.core.ownership;
34 import dlib.image.color;
35 
36 import dagon.core.bindings;
37 import dagon.graphics.entity;
38 import dagon.graphics.shader;
39 import dagon.graphics.terrain;
40 import dagon.graphics.particles;
41 import dagon.render.pipeline;
42 import dagon.render.pass;
43 import dagon.render.framebuffer;
44 import dagon.render.gbuffer;
45 import dagon.render.shaders.forward;
46 
47 class PassForward: RenderPass
48 {
49     ForwardShader forwardShader;
50     Framebuffer outputBuffer;
51     GBuffer gbuffer;
52     GLuint framebuffer = 0;
53 
54     this(RenderPipeline pipeline, GBuffer gbuffer, EntityGroup group = null)
55     {
56         super(pipeline, group);
57         forwardShader = New!ForwardShader(this);
58         
59         this.gbuffer = gbuffer;
60     }
61     
62     void prepareFramebuffer()
63     {
64         if (framebuffer)
65             return;
66     
67         glGenFramebuffers(1, &framebuffer);
68         glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
69         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, outputBuffer.colorTexture, 0);
70         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1, GL_TEXTURE_2D, gbuffer.velocityTexture, 0);
71         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_TEXTURE_2D, outputBuffer.depthTexture, 0);
72         
73         GLenum[2] drawBuffers = 
74         [
75             GL_COLOR_ATTACHMENT0, 
76             GL_COLOR_ATTACHMENT1
77         ];
78         
79         glDrawBuffers(drawBuffers.length, drawBuffers.ptr);
80 
81         GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
82         if (status != GL_FRAMEBUFFER_COMPLETE)
83             writeln(status);
84 
85         glBindFramebuffer(GL_FRAMEBUFFER, 0);
86     }
87     
88     void resize(uint w, uint h)
89     {
90         if (glIsFramebuffer(framebuffer))
91         {
92             glDeleteFramebuffers(1, &framebuffer);
93             framebuffer = 0;
94         }
95     }
96 
97     override void render()
98     {
99         if (group && outputBuffer)
100         {
101             state.environment = pipeline.environment;
102             
103             prepareFramebuffer();
104             
105             glBindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
106 
107             // TODO: move depth blit to separate stage
108             glBindFramebuffer(GL_READ_FRAMEBUFFER, gbuffer.framebuffer);
109             glBlitFramebuffer(0, 0, gbuffer.width, gbuffer.height, 0, 0, gbuffer.width, gbuffer.height, GL_DEPTH_BUFFER_BIT, GL_NEAREST);
110             glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
111 
112             glScissor(0, 0, outputBuffer.width, outputBuffer.height);
113             glViewport(0, 0, outputBuffer.width, outputBuffer.height);
114             
115             glEnablei(GL_BLEND, 0);
116             glEnablei(GL_BLEND, 1);
117             glBlendFunci(0, GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
118 
119             foreach(entity; group)
120             {
121                 if (entity.visible && entity.drawable)
122                 {
123                     if (!entityIsTerrain(entity) && !entityIsParticleSystem(entity))
124                     {
125                         Shader shader = forwardShader;
126 
127                         if (entity.material)
128                         {
129                             if (entity.material.shader)
130                                 shader = entity.material.shader;
131                         }
132 
133                         shader.bind();
134                         renderEntity(entity, shader);
135                         shader.unbind();
136                     }
137                 }
138             }
139 
140             glDisablei(GL_BLEND, 0);
141             glDisablei(GL_BLEND, 1);
142 
143             glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
144         }
145     }
146 }