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Initial draft of sokol backend

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Edward R. Gonzalez
2024-06-30 20:50:50 -04:00
parent f6a3f50fa1
commit 2cdc85af43
5 changed files with 748 additions and 0 deletions
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616
backend/sokol/backend_sokol.odin Normal file
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package ve_sokol
import ve "../../VEFontCache"
import gfx "thirdparty:sokol/gfx"
import glue "thirdparty:sokol/glue"
Context :: struct {
draw_list_vbuf : gfx.Buffer,
draw_list_ibuf : gfx.Buffer,
glyph_shader : gfx.Shader,
atlas_shader : gfx.Shader,
screen_shader : gfx.Shader,
// 2k x 512, R8
glyph_rt_color : gfx.Image,
glyph_rt_depth : gfx.Image,
glyph_rt_sampler : gfx.Sampler,
// 4k x 2k, R8
atlas_rt_color : gfx.Image,
atlas_rt_depth : gfx.Image,
atlas_rt_sampler : gfx.Sampler,
glyph_pipeline : gfx.Pipeline,
atlas_pipeline : gfx.Pipeline,
screen_pipeline : gfx.Pipeline,
glyph_pass : gfx.Pass,
atlas_pass : gfx.Pass,
screen_pass : gfx.Pass,
}
setup_gfx_objects :: proc( ctx : ^Context, ve_ctx : ve.Context, vert_cap, index_cap : int )
{
using ctx
Attachment_Desc :: gfx.Attachment_Desc
Blend_Factor :: gfx.Blend_Factor
Blend_Op :: gfx.Blend_Op
Blend_State :: gfx.Blend_State
Border_Color :: gfx.Border_Color
Buffer_Desciption :: gfx.Buffer_Desc
Buffer_Usage :: gfx.Usage
Buffer_Type :: gfx.Buffer_Type
Color_Target_State :: gfx.Color_Target_State
Filter :: gfx.Filter
Image_Desc :: gfx.Image_Desc
Pass_Action :: gfx.Pass_Action
Range :: gfx.Range
Resource_State :: gfx.Resource_State
Sampler_Description :: gfx.Sampler_Desc
Wrap :: gfx.Wrap
Vertex_Attribute_State :: gfx.Vertex_Attr_State
Vertex_Buffer_Layout_State :: gfx.Vertex_Buffer_Layout_State
Vertex_Index_Type :: gfx.Index_Type
Vertex_Format :: gfx.Vertex_Format
Vertex_Layout_State :: gfx.Vertex_Layout_State
Vertex_Step :: gfx.Vertex_Step
backend := gfx.query_backend()
app_env := glue.environment()
glyph_shader = gfx.make_shader(render_glyph_shader_desc(backend) )
atlas_shader = gfx.make_shader(blit_atlas_shader_desc(backend) )
screen_shader = gfx.make_shader(draw_text_shader_desc(backend) )
draw_list_vbuf = gfx.make_buffer( Buffer_Desciption {
size = size_of([4]f32) * vert_cap,
usage = Buffer_Usage.STREAM,
type = Buffer_Type.VERTEXBUFFER,
})
assert( gfx.query_buffer_state( draw_list_vbuf) < Resource_State.FAILED, "Failed to make draw_list_vbuf" )
draw_list_ibuf = gfx.make_buffer( Buffer_Desciption {
size = size_of(u32) * index_cap,
usage = Buffer_Usage.STREAM,
type = Buffer_Type.INDEXBUFFER,
})
assert( gfx.query_buffer_state( draw_list_ibuf) < Resource_State.FAILED, "Failed to make draw_list_iubuf" )
Image_Filter := Filter.LINEAR
// glyph_pipeline
{
vs_layout : Vertex_Layout_State
{
using vs_layout
attrs[ATTR_render_glyph_vs_v_position] = Vertex_Attribute_State {
format = Vertex_Format.FLOAT2,
offset = 0,
buffer_index = 0,
}
attrs[ATTR_render_glyph_vs_v_texture] = Vertex_Attribute_State {
format = Vertex_Format.FLOAT2,
offset = size_of(Vec2),
buffer_index = 0,
}
buffers[0] = VertexBufferLayoutState {
stride = size_of([4]f32),
step_func = Vertex_Step.PER_VERTEX
}
}
color_target := Color_Target_State {
pixel_format = .R8,
write_mask = .RGBA,
blend = Blend_State {
enabled = true,
src_factor_rgb = .ONE_MINUS_DST_COLOR,
dst_factor_rgb = .ONE_MINUS_SRC_COLOR,
op_rgb = Blend_Op.ADD,
src_factor_alpha = .ONE_MINUS_DST_ALPHA,
dst_factor_alpha = .ONE_MINUS_SRC_ALPHA,
op_alpha = Blend_Op.ADD,
},
}
glyph_pipeline = gfx.make_pipeline({
shader = glyph_shader,
layout = vs_layout,
index_type = Vertex_Index_Type.UINT32,
colors = {
0 = color_target,
},
color_count = 1,
depth = {
pixel_format = .DEPTH,
compare = .ALWAYS,
write_enabled = false,
},
cull_mode = .NONE,
sample_count = 1,
// label =
})
assert( gfx.query_pipeline_state(glyph_pipeline) < Resource_State.FAILED, "Failed to make glyph_pipeline" )
}
// glyph_pass
{
glyph_rt_color = gfx.make_image( Image_Desc {
type = ._2D,
render_target = true,
width = i32(ve_ctx.glyph_buffer.width),
height = i32(ve_ctx.glyph_buffer.height),
num_slices = 1,
num_mipmaps = 1,
usage = .IMMUTABLE,
pixel_format = .R8,
sample_count = 1,
// TODO(Ed): Setup labels for debug tracing/logging
// label =
})
assert( gfx.query_image_state(glyph_rt_color) < ResourceState.FAILED, "Failed to make glyph_pipeline" )
glyph_rt_depth = gfx.make_image( Image_Desc {
type = ._2D,
render_target = true,
width = i32(ve_ctx.glyph_buffer.width),
height = i32(ve_ctx.glyph_buffer.height),
num_slices = 1,
num_mipmaps = 1,
usage = .IMMUTABLE,
pixel_format = .DEPTH,
sample_count = 1,
})
glyph_rt_sampler = gfx.make_sampler( Sampler_Description {
min_filter = Image_Filter,
mag_filter = Image_Filter,
mipmap_filter = Filter.NONE,
wrap_u = .CLAMP_TO_EDGE,
wrap_v = .CLAMP_TO_EDGE,
min_lod = -1000.0,
max_lod = 1000.0,
border_color = BorderColor.OPAQUE_BLACK,
compare = .NEVER,
max_anisotropy = 1,
})
assert( gfx.query_sampler_state( glyph_rt_sampler) < Resource_State.FAILED, "Failed to make atlas_rt_sampler" )
color_attach := Attachment_Desc {
image = glyph_rt_color,
}
glyph_attachments := gfx.make_attachments({
colors = {
0 = color_attach,
},
depth_stencil = {
image = glyph_rt_depth,
},
})
assert( gfx.query_attachments_state(glyph_attachments) < Resource_State.FAILED, "Failed to make glyph_attachments" )
glyph_action := Pass_Action {
colors = {
0 = {
load_action = .LOAD,
store_action = .STORE,
clear_value = {0.00, 0.00, 0.00, 1.00},
}
},
depth = {
load_action = .DONTCARE,
store_action = .DONTCARE,
clear_value = 0.0,
},
stencil = {
load_action = .DONTCARE,
store_action = .DONTCARE,
clear_value = 0,
}
}
glyph_pass = gfx.Pass {
action = glyph_action,
attachments = glyph_attachments,
// label =
}
}
// atlas_pipeline
{
vs_layout : VertexLayoutState
{
using vs_layout
attrs[ATTR_ve_blit_atlas_vs_v_position] = Vertex_Attribute_State {
format = Vertex_Format.FLOAT2,
offset = 0,
buffer_index = 0,
}
attrs[ATTR_ve_blit_atlas_vs_v_texture] = Vertex_Attribute_State {
format = Vertex_Format.FLOAT2,
offset = size_of(Vec2),
buffer_index = 0,
}
buffers[0] = Vertex_Buffer_Layout_State {
stride = size_of([4]f32),
step_func = Vertex_Step.PER_VERTEX
}
}
color_target := Color_Target_State {
pixel_format = .R8,
write_mask = .RGBA,
blend = Blend_State {
enabled = true,
src_factor_rgb = .SRC_ALPHA,
dst_factor_rgb = .ONE_MINUS_SRC_ALPHA,
op_rgb = Blend_Op.ADD,
src_factor_alpha = .SRC_ALPHA,
dst_factor_alpha = .ONE_MINUS_SRC_ALPHA,
op_alpha = Blend_Op.ADD,
},
}
atlas_pipeline = gfx.make_pipeline({
shader = atlas_shader,
layout = vs_layout,
index_type = Vertex_Index_Type.UINT32,
colors = {
0 = color_target,
},
color_count = 1,
depth = {
pixel_format = .DEPTH,
compare = .ALWAYS,
write_enabled = false,
},
cull_mode = .NONE,
sample_count = 1,
})
}
// atlas_pass
{
atlas_rt_color = gfx.make_image( Image_Desc {
type = ._2D,
render_target = true,
width = i32(ve_ctx.atlas.width),
height = i32(ve_ctx.atlas.height),
num_slices = 1,
num_mipmaps = 1,
usage = .IMMUTABLE,
pixel_format = .R8,
sample_count = 1,
// TODO(Ed): Setup labels for debug tracing/logging
// label =
})
assert( gfx.query_image_state(atlas_rt_color) < Resource_State.FAILED, "Failed to make atlas_rt_color")
atlas_rt_depth = gfx.make_image( Image_Desc {
type = ._2D,
render_target = true,
width = i32(ve_ctx.atlas.width),
height = i32(ve_ctx.atlas.height),
num_slices = 1,
num_mipmaps = 1,
usage = .IMMUTABLE,
pixel_format = .DEPTH,
sample_count = 1,
})
assert( gfx.query_image_state(atlas_rt_depth) < Resource_State.FAILED, "Failed to make atlas_rt_depth")
atlas_rt_sampler = gfx.make_sampler( Sampler_Description {
min_filter = Image_Filter,
mag_filter = Image_Filter,
mipmap_filter = Filter.NONE,
wrap_u = .CLAMP_TO_EDGE,
wrap_v = .CLAMP_TO_EDGE,
min_lod = -1000.0,
max_lod = 1000.0,
border_color = Border_Color.OPAQUE_BLACK,
compare = .NEVER,
max_anisotropy = 1,
})
assert( gfx.query_sampler_state( atlas_rt_sampler) < Resource_State.FAILED, "Failed to make atlas_rt_sampler" )
color_attach := Attachment_Desc {
image = atlas_rt_color,
// mip_level = 1,
}
atlas_attachments := gfx.make_attachments({
colors = {
0 = color_attach,
},
depth_stencil = {
image = atlas_rt_depth,
},
})
assert( gfx.query_attachments_state(atlas_attachments) < Resource_State.FAILED, "Failed to make atlas_attachments")
atlas_action := Pass_Action {
colors = {
0 = {
load_action = .LOAD,
store_action = .STORE,
clear_value = {0.00, 0.00, 0.00, 1.0},
}
},
depth = {
load_action = .DONTCARE,
store_action = .DONTCARE,
clear_value = 0.0,
},
stencil = {
load_action = .DONTCARE,
store_action = .DONTCARE,
clear_value = 0,
}
}
atlas_pass = gfx.Pass {
action = atlas_action,
attachments = atlas_attachments,
// label =
}
}
// screen pipeline
{
vs_layout : Vertex_Layout_State
{
using vs_layout
attrs[ATTR_ve_draw_text_vs_v_position] = Vertex_Attribute_State {
format = Vertex_Format.FLOAT2,
offset = 0,
buffer_index = 0,
}
attrs[ATTR_ve_draw_text_vs_v_texture] = Vertex_Attribute_State {
format = Vertex_Format.FLOAT2,
offset = size_of(Vec2),
buffer_index = 0,
}
buffers[0] = Vertex_Buffer_Layout_State {
stride = size_of([4]f32),
step_func = Vertex_Step.PER_VERTEX
}
}
color_target := Color_Target_State {
pixel_format = app_env.defaults.color_format,
write_mask = .RGBA,
blend = Blend_State {
enabled = true,
src_factor_rgb = .SRC_ALPHA,
dst_factor_rgb = .ONE_MINUS_SRC_ALPHA,
op_rgb = BlendOp.ADD,
src_factor_alpha = .SRC_ALPHA,
dst_factor_alpha = .ONE_MINUS_SRC_ALPHA,
op_alpha = BlendOp.ADD,
},
}
screen_pipeline = gfx.make_pipeline({
shader = screen_shader,
layout = vs_layout,
index_type = Vertex_Index_Type.UINT32,
colors = {
0 = color_target,
},
color_count = 1,
sample_count = 1,
depth = {
pixel_format = app_env.defaults.depth_format,
compare = .ALWAYS,
write_enabled = false,
},
cull_mode = .NONE,
})
verify( gfx.query_pipeline_state(screen_pipeline) < Resource_State.FAILED, "Failed to make screen_pipeline" )
}
// screen_pass
{
screen_action := Pass_Action {
colors = {
0 = {
load_action = .LOAD,
store_action = .STORE,
clear_value = {0.00, 0.00, 0.00, 0.0},
},
1 = {
load_action = .LOAD,
store_action = .STORE,
clear_value = {0.00, 0.00, 0.00, 0.0},
},
2 = {
load_action = .LOAD,
store_action = .STORE,
clear_value = {0.00, 0.00, 0.00, 0.0},
}
},
depth = {
load_action = .DONTCARE,
store_action = .DONTCARE,
clear_value = 0.0,
},
stencil = {
load_action = .DONTCARE,
store_action = .DONTCARE,
clear_value = 0,
}
}
screen_pass = gfx.Pass {
action = screen_action,
// label =
}
}
}
render_text_layer :: proc( screen_extent : Vec2, ve_ctx : ^ve.Context, ctx : Context )
{
// profile("VEFontCache: render text layer")
using ctx
Bindings :: gfx.Bindings
Range :: gfx.Range
ShaderStage :: gfx.Shader_Stage
vbuf_layer_slice, ibuf_layer_slice, calls_layer_slice := ve.get_draw_list_layer( ve_ctx )
vbuf_ve_range := Range{ raw_data(vbuf_layer_slice), cast(u64) len(vbuf_layer_slice) * size_of(ve.Vertex) }
ibuf_ve_range := Range{ raw_data(ibuf_layer_slice), cast(u64) len(ibuf_layer_slice) * size_of(u32) }
gfx.append_buffer( draw_list_vbuf, vbuf_ve_range )
gfx.append_buffer( draw_list_ibuf, ibuf_ve_range )
ve.flush_draw_list_layer( ve_ctx )
screen_width := u32(screen_extent.x * 2)
screen_height := u32(screen_extent.y * 2)
for & draw_call in calls_layer_slice
{
watch := draw_call
// profile("VEFontCache: draw call")
num_indices := draw_call.end_index - draw_call.start_index
switch draw_call.pass
{
// 1. Do the glyph rendering pass
// Glyphs are first rendered to an intermediate 2k x 512px R8 texture
case .Glyph:
// profile("VEFontCache: draw call: glyph")
if num_indices == 0 && ! draw_call.clear_before_draw {
continue
}
width := ve_ctx.glyph_buffer.width
height := ve_ctx.glyph_buffer.height
pass := glyph_pass
if draw_call.clear_before_draw {
pass.action.colors[0].load_action = .CLEAR
pass.action.colors[0].clear_value.a = 1.0
}
gfx.begin_pass( pass )
gfx.apply_viewport( 0,0, width, height, origin_top_left = true )
gfx.apply_scissor_rect( 0,0, width, height, origin_top_left = true )
gfx.apply_pipeline( glyph_pipeline )
bindings := Bindings {
vertex_buffers = {
0 = draw_list_vbuf,
},
vertex_buffer_offsets = {
0 = 0,
},
index_buffer = draw_list_ibuf,
index_buffer_offset = 0,//i32(draw_call.start_index) * size_of(u32),
fs = {},
}
gfx.apply_bindings( bindings )
// 2. Do the atlas rendering pass
// A simple 16-tap box downsample shader is then used to blit from this intermediate texture to the final atlas location
case .Atlas:
// profile("VEFontCache: draw call: atlas")
if num_indices == 0 && ! draw_call.clear_before_draw {
continue
}
width := ve_ctx.atlas.width
height := ve_ctx.atlas.height
pass := atlas_pass
if draw_call.clear_before_draw {
pass.action.colors[0].load_action = .CLEAR
pass.action.colors[0].clear_value.a = 1.0
}
gfx.begin_pass( pass )
gfx.apply_viewport( 0, 0, width, height, origin_top_left = true )
gfx.apply_scissor_rect( 0, 0, width, height, origin_top_left = true )
gfx.apply_pipeline( atlas_pipeline )
fs_uniform := Ve_Blit_Atlas_Fs_Params { region = cast(i32) draw_call.region }
gfx.apply_uniforms( ShaderStage.FS, SLOT_ve_blit_atlas_fs_params, Range { & fs_uniform, size_of(Ve_Blit_Atlas_Fs_Params) })
gfx.apply_bindings(Bindings {
vertex_buffers = {
0 = draw_list_vbuf,
},
vertex_buffer_offsets = {
0 = 0,
},
index_buffer = draw_list_ibuf,
index_buffer_offset = 0,//i32(draw_call.start_index) * size_of(u32),
fs = {
images = { SLOT_ve_blit_atlas_src_texture = glyph_rt_color, },
samplers = { SLOT_ve_blit_atlas_src_sampler = glyph_rt_sampler, },
},
})
// 3. Use the atlas to then render the text.
case .None, .Target, .Target_Uncached:
if num_indices == 0 && ! draw_call.clear_before_draw {
continue
}
// profile("VEFontCache: draw call: target")
pass := screen_pass
pass.swapchain = sokol_glue.swapchain()
gfx.begin_pass( pass )
gfx.apply_viewport( 0, 0, screen_width, screen_height, origin_top_left = true )
gfx.apply_scissor_rect( 0, 0, screen_width, screen_height, origin_top_left = true )
gfx.apply_pipeline( screen_pipeline )
src_rt := atlas_rt_color
src_sampler := atlas_rt_sampler
fs_target_uniform := Ve_Draw_Text_Fs_Params {
down_sample = 0,
colour = draw_call.colour,
}
if draw_call.pass == .Target_Uncached {
fs_target_uniform.down_sample = 1
src_rt = glyph_rt_color
src_sampler = glyph_rt_sampler
}
gfx.apply_uniforms( ShaderStage.FS, SLOT_ve_draw_text_fs_params, Range { & fs_target_uniform, size_of(Ve_Draw_Text_Fs_Params) })
gfx.apply_bindings(Bindings {
vertex_buffers = {
0 = draw_list_vbuf,
},
vertex_buffer_offsets = {
0 = 0,
},
index_buffer = draw_list_ibuf,
index_buffer_offset = 0,//i32(draw_call.start_index) * size_of(u32),
fs = {
images = { SLOT_ve_draw_text_src_texture = src_rt, },
samplers = { SLOT_ve_draw_text_src_sampler = src_sampler, },
},
})
}
if num_indices != 0 {
gfx.draw( draw_call.start_index, num_indices, 1 )
}
gfx.end_pass()
}
}

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backend/sokol/blit_atlas.shdc.glsl Normal file
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@module blit_atlas
@header package ve_sokol
@header import sg "thirdparty:sokol/gfx"
@vs blit_atlas_vs
@include ./source_shared.shdc.glsl
@end
@fs blit_atlas_fs
in vec2 uv;
out vec4 frag_color;
uniform texture2D blit_atlas_src_texture;
uniform sampler blit_atlas_src_sampler;
uniform ve_blit_atlas_fs_params {
int region;
};
float down_sample( vec2 uv, vec2 texture_size )
{
float down_sample_scale = 1.0f / 4.0f;
float value =
texture(sampler2D( blit_atlas_src_texture, blit_atlas_src_sampler ), uv + vec2( 0.0f, 0.0f ) * texture_size ).x * down_sample_scale
+ texture(sampler2D( blit_atlas_src_texture, blit_atlas_src_sampler ), uv + vec2( 0.0f, 1.0f ) * texture_size ).x * down_sample_scale
+ texture(sampler2D( blit_atlas_src_texture, blit_atlas_src_sampler ), uv + vec2( 1.0f, 0.0f ) * texture_size ).x * down_sample_scale
+ texture(sampler2D( blit_atlas_src_texture, blit_atlas_src_sampler ), uv + vec2( 1.0f, 1.0f ) * texture_size ).x * down_sample_scale;
return value;
}
void main()
{
// TODO(Ed): The original author made these consts, I want to instead expose as uniforms...
const vec2 texture_size = 1.0f / vec2( 2048.0f, 512.0f ); // VEFontCache.Context.buffer_width/buffer_height
if ( region == 0 || region == 1 || region == 2 )
{
float down_sample_scale = 1.0f / 4.0f;
float alpha =
down_sample( uv + vec2( -1.0f, -1.5f ) * texture_size, texture_size ) * down_sample_scale
+ down_sample( uv + vec2( 0.5f, -1.5f ) * texture_size, texture_size ) * down_sample_scale
+ down_sample( uv + vec2( -1.5f, 0.5f ) * texture_size, texture_size ) * down_sample_scale
+ down_sample( uv + vec2( 0.5f, 0.5f ) * texture_size, texture_size ) * down_sample_scale;
frag_color = vec4( 1.0f, 1.0f, 1.0f, alpha );
}
else
{
frag_color = vec4( 0.0f, 0.0f, 0.0f, 1.0 );
}
}
@end
@program blit_atlas blit_atlas_vs blit_atlas_fs

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backend/sokol/draw_text.shdc.glsl Normal file
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@module draw_text
@header package ve_sokol
@header import sg "thirdparty:sokol/gfx"
@vs draw_text_vs
in vec2 v_position;
in vec2 v_texture;
out vec2 uv;
void main()
{
uv = vec2( v_texture.x, 1 - v_texture.y );
gl_Position = vec4( v_position * 2.0f - 1.0f, 0.0f, 1.0f );
}
@end
@fs draw_text_fs
in vec2 uv;
out vec4 frag_color;
uniform texture2D draw_text_src_texture;
uniform sampler draw_text_src_sampler;
uniform draw_text_fs_params {
int down_sample;
vec4 colour;
};
void main()
{
float alpha = texture(sampler2D( draw_text_src_texture, draw_text_src_sampler ), uv ).x;
if ( down_sample == 1 )
{
// TODO(Ed): The original author made these consts, I want to instead expose as uniforms...
const vec2 texture_size = 1.0f / vec2( 2048.0f, 512.0f ); // VEFontCache.Context.buffer_width/buffer_height
alpha =
(texture(sampler2D( draw_text_src_texture, draw_text_src_sampler), uv + vec2( -0.5f, -0.5f) * texture_size ).x * 0.25f)
+ (texture(sampler2D( draw_text_src_texture, draw_text_src_sampler), uv + vec2( -0.5f, 0.5f) * texture_size ).x * 0.25f)
+ (texture(sampler2D( draw_text_src_texture, draw_text_src_sampler), uv + vec2( 0.5f, -0.5f) * texture_size ).x * 0.25f)
+ (texture(sampler2D( draw_text_src_texture, draw_text_src_sampler), uv + vec2( 0.5f, 0.5f) * texture_size ).x * 0.25f);
}
frag_color = vec4( colour.xyz, colour.a * alpha );
}
@end
@program draw_text draw_text_vs draw_text_fs

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backend/sokol/render_glyph.shdc.glsl Normal file
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@module render_glyph
@header package ve_sokol
@header import sg "thirdparty:sokol/gfx"
@vs render_glyph_vs
@include ./ve_source_shared.shdc.glsl
@end
@fs render_glyph_fs
in vec2 uv;
out vec4 frag_color;
void main()
{
frag_color = vec4( 1.0, 1.0, 1.0, 1.0 );
}
@end
@program render_glyph render_glyph_vs render_glyph_fs

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backend/sokol/source_shared.shdc.glsl Normal file
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in vec2 v_position;
in vec2 v_texture;
// in vec4 v_elem;
out vec2 uv;
void main()
{
uv = vec2( v_texture.x, 1 - v_texture.y );
gl_Position = vec4( v_position, 0.0, 1.0 );
}