implement box blur for ssao

src/rendering/backend_sokol.jai

@@ -256,8 +256,7 @@ backend_process_command_buckets :: () {
     in_gbuffer_pass = false;
     current_trile_offset_index = 0; // This is not optimal, but it is nice and simple.
 
-    // --- TODO: Do SSAO pass here:
+    sg_begin_pass(*(sg_pass.{ action = state.pass_action_clear, attachments = g_postprocess_attach_a }));
-    sg_begin_pass(*(sg_pass.{ action = state.pass_action_clear, attachments = g_ssao_attachments}));
     sg_apply_pipeline(gPipelines.ssao.pipeline);
     gPipelines.ssao.bind.images[0] = g_gbuf_position;
     gPipelines.ssao.bind.images[1] = g_gbuf_normal;
@@ -272,6 +271,13 @@ backend_process_command_buckets :: () {
     sg_draw(0, 6, 1);    
     sg_end_pass();
 
+    sg_begin_pass(*(sg_pass.{ action = state.pass_action_clear, attachments = g_ssao_attachments }));
+    sg_apply_pipeline(gPipelines.op.pipeline);
+    gPipelines.op.bind.images[0] = g_postprocess_a;
+    sg_apply_bindings(*gPipelines.op.bind);
+    sg_draw(0, 6, 1);    
+    sg_end_pass();
+
     // 5. Main pass
 	sg_begin_pass(*(sg_pass.{ action = state.pass_action_clear, attachments = g_rendertex_attachments}));
     for render_command_buckets.main {

src/rendering/pipelines.jai

@@ -28,6 +28,14 @@ g_ssao_noise_buf        : sg_image;
 g_ssaobuf_depth         : sg_image;
 g_ssao_attachments      : sg_attachments;
 
+g_postprocess_a         : sg_image;
+g_postprocess_b         : sg_image;
+g_postprocess_a_depth   : sg_image;
+g_postprocess_b_depth   : sg_image;
+g_postprocess_attach_a  : sg_attachments;
+g_postprocess_attach_b  : sg_attachments;
+  
+
 gPipelines : struct {
     // G-Buffer generation for SSAO and other effects
     gbuffer: Pipeline_Binding;
@@ -52,6 +60,8 @@ gPipelines : struct {
     // Post-processing pipeline
     postprocess : Pipeline_Binding;
 
+    op : Pipeline_Binding;
+
     // Renders the SSAO texture using things from the gbuffer pass.
     ssao: Pipeline_Binding;
 }
@@ -125,6 +135,7 @@ create_pipelines :: () {
     create_plane_pipeline();
     create_postprocess_pipeline();
     create_ssao_pipeline();
+    create_op_pipeline();
     
     create_shadowmap_image();
     create_final_image();
@@ -678,9 +689,73 @@ create_postprocess_pipeline :: () {
 
 }
 
+create_op_pipeline :: () {
+    platconf := get_plat_conf();
+    pipeline: sg_pipeline_desc;
+    shader_desc := op_shader_desc(sg_query_backend());
+    pipeline.shader = sg_make_shader(*shader_desc);
+
+    pipeline.layout.attrs[ATTR_op_position] = .{ format = .FLOAT2 };
+    pipeline.layout.attrs[ATTR_op_uv]       = .{ format = .FLOAT2 };
+    pipeline.index_type = .UINT16;
+
+    color_state := sg_color_target_state.{
+        blend = .{
+            enabled = true,
+            src_factor_rgb = .SRC_ALPHA,
+            dst_factor_rgb = .ONE_MINUS_SRC_ALPHA
+        }
+    };
+    pipeline.depth = .{
+            write_enabled = true,
+            compare = .LESS_EQUAL,
+            pixel_format = .DEPTH
+    };
+
+    pipeline.color_count = 1;
+    pipeline.colors[0] = color_state;
+
+    gPipelines.op.pipeline = sg_make_pipeline(*pipeline);
+
+    quad_vertices : [16]float = .[
+        -1.0,  1.0, 0.0, flip_if_plat(1.0), // top-let
+        -1.0, -1.0, 0.0, flip_if_plat(0.0), // bottom-let
+         1.0, -1.0, 1.0, flip_if_plat(0.0), // bottom-right
+         1.0,  1.0, 1.0, flip_if_plat(1.0), // top-right
+    ];
+    quad_indices  : [6]u16 = .[
+        0, 1, 2, 0, 2, 3
+    ];
+
+    vbuffer := sg_buffer_desc.{ size = size_of(float) * 16, data = .{
+        ptr = quad_vertices.data,
+        size = 16 * 4
+    }};
+    ibuffer := sg_buffer_desc.{ size = size_of(u16) * 6, data = .{
+        ptr = quad_indices.data,
+        size = 6 * 2
+    },
+    type = .INDEXBUFFER,
+    };
+
+    gPipelines.op.bind.vertex_buffers[0] = sg_make_buffer(*vbuffer);
+    gPipelines.op.bind.index_buffer = sg_make_buffer(*ibuffer);
+    gPipelines.op.bind.samplers[0] = sg_make_sampler(*(sg_sampler_desc.{
+        wrap_u = .CLAMP_TO_EDGE,
+        wrap_v = .CLAMP_TO_EDGE,
+        min_filter = .NEAREST,
+        mag_filter = .NEAREST,
+    }));
+
+}
+
 create_ssao_images :: () {
     if g_ssaobuf.id != INVALID_ID then sg_destroy_image(g_ssaobuf);
     if g_ssaobuf_depth.id != INVALID_ID then sg_destroy_image(g_ssaobuf_depth);
+    if g_postprocess_a.id != INVALID_ID then sg_destroy_image(g_postprocess_a);
+    if g_postprocess_a_depth.id != INVALID_ID then sg_destroy_image(g_postprocess_a_depth);
+    if g_postprocess_b.id != INVALID_ID then sg_destroy_image(g_postprocess_b);
+    if g_postprocess_b_depth.id != INVALID_ID then sg_destroy_image(g_postprocess_b_depth);
     w,h := get_render_size();
     img_desc := sg_image_desc.{
         width = w,
@@ -689,6 +764,8 @@ create_ssao_images :: () {
     };
     img_desc.sample_count = 1;
     g_ssaobuf = sg_make_image(*img_desc);
+    g_postprocess_a = sg_make_image(*img_desc);
+    g_postprocess_b = sg_make_image(*img_desc);
     img_desc = sg_image_desc.{
         width = w,
         height = h,
@@ -697,13 +774,28 @@ create_ssao_images :: () {
     };
     img_desc.sample_count = 1;
     g_ssaobuf_depth = sg_make_image(*img_desc);
-
+    g_postprocess_a_depth = sg_make_image(*img_desc);
+    g_postprocess_b_depth = sg_make_image(*img_desc);
+    
 	attachmentsDesc := sg_attachments_desc.{
 	    colors[0].image = g_ssaobuf,
         depth_stencil.image = g_ssaobuf_depth
 	};
     sg_destroy_attachments(g_ssao_attachments);
     g_ssao_attachments = sg_make_attachments(*attachmentsDesc);
+    
+	attachmentsDescA := sg_attachments_desc.{
+	    colors[0].image = g_postprocess_a,
+        depth_stencil.image = g_postprocess_a_depth
+	};
+	attachmentsDescB := sg_attachments_desc.{
+	    colors[0].image = g_postprocess_b,
+        depth_stencil.image = g_postprocess_b_depth
+	};
+    sg_destroy_attachments(g_postprocess_attach_a);
+    g_postprocess_attach_a = sg_make_attachments(*attachmentsDescA);
+    sg_destroy_attachments(g_postprocess_attach_b);
+    g_postprocess_attach_b = sg_make_attachments(*attachmentsDescB);
 }
 
 create_ssao_pipeline :: () {

src/shaders/jai/shader_op.jai

@@ -0,0 +1,420 @@
+/*
+    #version:1# (machine generated, don't edit!)
+
+    Generated by sokol-shdc (https://github.com/floooh/sokol-tools)
+
+    Cmdline:
+        sokol-shdc -i shader_op.glsl -o ./jai/shader_op.jai -l glsl430:glsl300es:metal_macos -f sokol_jai
+
+    Overview:
+    =========
+    Shader program: 'op':
+        Get shader desc: op_shader_desc(sg_query_backend())
+        Vertex Shader: vs_op
+        Fragment Shader: fs_op
+        Attributes:
+            ATTR_op_position => 0
+            ATTR_op_uv => 1
+    Bindings:
+        Image 'optex':
+            Image type: ._2D
+            Sample type: .FLOAT
+            Multisampled: false
+            Bind slot: IMG_optex => 0
+        Sampler 'opsmp':
+            Type: .FILTERING
+            Bind slot: SMP_opsmp => 0
+*/
+ATTR_op_position :: 0;
+ATTR_op_uv :: 1;
+IMG_optex :: 0;
+SMP_opsmp :: 0;
+/*
+    #version 430
+
+    layout(location = 0) in vec2 position;
+    layout(location = 0) out vec2 texcoord;
+    layout(location = 1) in vec2 uv;
+
+    void main()
+    {
+        gl_Position = vec4(position, 0.5, 1.0);
+        texcoord = uv;
+    }
+
+*/
+vs_op_source_glsl430 := u8.[
+    0x23,0x76,0x65,0x72,0x73,0x69,0x6f,0x6e,0x20,0x34,0x33,0x30,0x0a,0x0a,0x6c,0x61,
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+
+];
+/*
+    #version 430
+
+    layout(binding = 16) uniform sampler2D optex_opsmp;
+
+    layout(location = 0) in vec2 texcoord;
+    layout(location = 0) out vec4 frag_color;
+
+    void main()
+    {
+        vec2 _28 = vec2(1.0) / vec2(textureSize(optex_opsmp, 0));
+        float result = 0.0;
+        for (int x = -3; x < 3; x++)
+        {
+            for (int y = -3; y < 3; y++)
+            {
+                result += texture(optex_opsmp, texcoord + (vec2(float(x), float(y)) * _28)).x;
+            }
+        }
+        float _84 = result * 0.02777777798473834991455078125;
+        frag_color = vec4(_84, _84, _84, 1.0);
+    }
+
+*/
+fs_op_source_glsl430 := u8.[
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+    0x0a,0x0a,0x00,
+];
+/*
+    #version 300 es
+
+    layout(location = 0) in vec2 position;
+    out vec2 texcoord;
+    layout(location = 1) in vec2 uv;
+
+    void main()
+    {
+        gl_Position = vec4(position, 0.5, 1.0);
+        texcoord = uv;
+    }
+
+*/
+vs_op_source_glsl300es := u8.[
+    0x23,0x76,0x65,0x72,0x73,0x69,0x6f,0x6e,0x20,0x33,0x30,0x30,0x20,0x65,0x73,0x0a,
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+];
+/*
+    #version 300 es
+    precision mediump float;
+    precision highp int;
+
+    uniform highp sampler2D optex_opsmp;
+
+    in highp vec2 texcoord;
+    layout(location = 0) out highp vec4 frag_color;
+
+    void main()
+    {
+        highp vec2 _28 = vec2(1.0) / vec2(textureSize(optex_opsmp, 0));
+        highp float result = 0.0;
+        for (int x = -3; x < 3; x++)
+        {
+            for (int y = -3; y < 3; y++)
+            {
+                result += texture(optex_opsmp, texcoord + (vec2(float(x), float(y)) * _28)).x;
+            }
+        }
+        highp float _84 = result * 0.02777777798473834991455078125;
+        frag_color = vec4(_84, _84, _84, 1.0);
+    }
+
+*/
+fs_op_source_glsl300es := u8.[
+    0x23,0x76,0x65,0x72,0x73,0x69,0x6f,0x6e,0x20,0x33,0x30,0x30,0x20,0x65,0x73,0x0a,
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+];
+/*
+    #include <metal_stdlib>
+    #include <simd/simd.h>
+
+    using namespace metal;
+
+    struct main0_out
+    {
+        float2 texcoord [[user(locn0)]];
+        float4 gl_Position [[position]];
+    };
+
+    struct main0_in
+    {
+        float2 position [[attribute(0)]];
+        float2 uv [[attribute(1)]];
+    };
+
+    vertex main0_out main0(main0_in in [[stage_in]])
+    {
+        main0_out out = {};
+        out.gl_Position = float4(in.position, 0.5, 1.0);
+        out.texcoord = in.uv;
+        return out;
+    }
+
+*/
+vs_op_source_metal_macos := u8.[
+    0x23,0x69,0x6e,0x63,0x6c,0x75,0x64,0x65,0x20,0x3c,0x6d,0x65,0x74,0x61,0x6c,0x5f,
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+    0x0a,0x0a,0x00,
+];
+/*
+    #include <metal_stdlib>
+    #include <simd/simd.h>
+
+    using namespace metal;
+
+    struct main0_out
+    {
+        float4 frag_color [[color(0)]];
+    };
+
+    struct main0_in
+    {
+        float2 texcoord [[user(locn0)]];
+    };
+
+    fragment main0_out main0(main0_in in [[stage_in]], texture2d<float> optex [[texture(0)]], sampler opsmp [[sampler(0)]])
+    {
+        main0_out out = {};
+        float2 _28 = float2(1.0) / float2(int2(optex.get_width(), optex.get_height()));
+        float result = 0.0;
+        for (int x = -3; x < 3; x++)
+        {
+            for (int y = -3; y < 3; y++)
+            {
+                result += optex.sample(opsmp, (in.texcoord + (float2(float(x), float(y)) * _28))).x;
+            }
+        }
+        float _84 = result * 0.02777777798473834991455078125;
+        out.frag_color = float4(_84, _84, _84, 1.0);
+        return out;
+    }
+
+*/
+fs_op_source_metal_macos := u8.[
+    0x23,0x69,0x6e,0x63,0x6c,0x75,0x64,0x65,0x20,0x3c,0x6d,0x65,0x74,0x61,0x6c,0x5f,
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+    0x78,0x3b,0x0a,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x7d,0x0a,0x20,0x20,0x20,
+    0x20,0x7d,0x0a,0x20,0x20,0x20,0x20,0x66,0x6c,0x6f,0x61,0x74,0x20,0x5f,0x38,0x34,
+    0x20,0x3d,0x20,0x72,0x65,0x73,0x75,0x6c,0x74,0x20,0x2a,0x20,0x30,0x2e,0x30,0x32,
+    0x37,0x37,0x37,0x37,0x37,0x37,0x37,0x39,0x38,0x34,0x37,0x33,0x38,0x33,0x34,0x39,
+    0x39,0x31,0x34,0x35,0x35,0x30,0x37,0x38,0x31,0x32,0x35,0x3b,0x0a,0x20,0x20,0x20,
+    0x20,0x6f,0x75,0x74,0x2e,0x66,0x72,0x61,0x67,0x5f,0x63,0x6f,0x6c,0x6f,0x72,0x20,
+    0x3d,0x20,0x66,0x6c,0x6f,0x61,0x74,0x34,0x28,0x5f,0x38,0x34,0x2c,0x20,0x5f,0x38,
+    0x34,0x2c,0x20,0x5f,0x38,0x34,0x2c,0x20,0x31,0x2e,0x30,0x29,0x3b,0x0a,0x20,0x20,
+    0x20,0x20,0x72,0x65,0x74,0x75,0x72,0x6e,0x20,0x6f,0x75,0x74,0x3b,0x0a,0x7d,0x0a,
+    0x0a,0x00,
+];
+op_shader_desc :: (backend: sg_backend) -> sg_shader_desc {
+    desc: sg_shader_desc;
+    desc.label = "op_shader";
+    if backend == {
+    case .GLCORE;
+        desc.vertex_func.source = xx *vs_op_source_glsl430;
+        desc.vertex_func.entry = "main";
+        desc.fragment_func.source = xx *fs_op_source_glsl430;
+        desc.fragment_func.entry = "main";
+        desc.attrs[0].base_type = .FLOAT;
+        desc.attrs[0].glsl_name = "position";
+        desc.attrs[1].base_type = .FLOAT;
+        desc.attrs[1].glsl_name = "uv";
+        desc.images[0].stage = .FRAGMENT;
+        desc.images[0].multisampled = false;
+        desc.images[0].image_type = ._2D;
+        desc.images[0].sample_type = .FLOAT;
+        desc.samplers[0].stage = .FRAGMENT;
+        desc.samplers[0].sampler_type = .FILTERING;
+        desc.image_sampler_pairs[0].stage = .FRAGMENT;
+        desc.image_sampler_pairs[0].image_slot = 0;
+        desc.image_sampler_pairs[0].sampler_slot = 0;
+        desc.image_sampler_pairs[0].glsl_name = "optex_opsmp";
+    case .GLES3;
+        desc.vertex_func.source = xx *vs_op_source_glsl300es;
+        desc.vertex_func.entry = "main";
+        desc.fragment_func.source = xx *fs_op_source_glsl300es;
+        desc.fragment_func.entry = "main";
+        desc.attrs[0].base_type = .FLOAT;
+        desc.attrs[0].glsl_name = "position";
+        desc.attrs[1].base_type = .FLOAT;
+        desc.attrs[1].glsl_name = "uv";
+        desc.images[0].stage = .FRAGMENT;
+        desc.images[0].multisampled = false;
+        desc.images[0].image_type = ._2D;
+        desc.images[0].sample_type = .FLOAT;
+        desc.samplers[0].stage = .FRAGMENT;
+        desc.samplers[0].sampler_type = .FILTERING;
+        desc.image_sampler_pairs[0].stage = .FRAGMENT;
+        desc.image_sampler_pairs[0].image_slot = 0;
+        desc.image_sampler_pairs[0].sampler_slot = 0;
+        desc.image_sampler_pairs[0].glsl_name = "optex_opsmp";
+    case .METAL_MACOS;
+        desc.vertex_func.source = xx *vs_op_source_metal_macos;
+        desc.vertex_func.entry = "main0";
+        desc.fragment_func.source = xx *fs_op_source_metal_macos;
+        desc.fragment_func.entry = "main0";
+        desc.attrs[0].base_type = .FLOAT;
+        desc.attrs[1].base_type = .FLOAT;
+        desc.images[0].stage = .FRAGMENT;
+        desc.images[0].multisampled = false;
+        desc.images[0].image_type = ._2D;
+        desc.images[0].sample_type = .FLOAT;
+        desc.images[0].msl_texture_n = 0;
+        desc.samplers[0].stage = .FRAGMENT;
+        desc.samplers[0].sampler_type = .FILTERING;
+        desc.samplers[0].msl_sampler_n = 0;
+        desc.image_sampler_pairs[0].stage = .FRAGMENT;
+        desc.image_sampler_pairs[0].image_slot = 0;
+        desc.image_sampler_pairs[0].sampler_slot = 0;
+    }
+    return desc;
+}

src/shaders/shader_op.glsl

@@ -0,0 +1,35 @@
+@vs vs_op
+in vec2 position;
+in vec2 uv;
+
+out vec2 texcoord;
+
+void main() {
+    gl_Position = vec4(position, 0.5, 1.0);
+    texcoord = uv;
+}
+@end
+
+@fs fs_op
+in vec2 texcoord;
+out vec4 frag_color;
+
+layout(binding = 0) uniform texture2D optex;
+layout(binding = 0) uniform sampler opsmp;
+
+void main() {
+    vec2 texelSize = 1.0 / vec2(textureSize(sampler2D(optex, opsmp), 0));
+    float result = 0.0;
+    for (int x = -2; x < 2; ++x) 
+    {
+        for (int y = -2; y < 2; ++y) 
+        {
+            vec2 offset = vec2(float(x), float(y)) * texelSize;
+            result += texture(sampler2D(optex, opsmp), texcoord + offset).r;
+        }
+    }
+    frag_color = vec4(vec3(result / (4.0 * 4.0)), 1.0);
+}
+@end
+
+@program op vs_op fs_op