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panopainter/src/paint_renderer/compositor.cpp

321 lines
12 KiB
C++

#include "paint_renderer/compositor.h"
#include <limits>
namespace pp::paint_renderer {
namespace {
[[nodiscard]] bool is_valid_blend_mode(pp::paint::BlendMode mode) noexcept
{
switch (mode) {
case pp::paint::BlendMode::normal:
case pp::paint::BlendMode::multiply:
case pp::paint::BlendMode::screen:
case pp::paint::BlendMode::color_dodge:
case pp::paint::BlendMode::overlay:
return true;
}
return false;
}
[[nodiscard]] bool is_valid_stroke_blend_mode(pp::paint::StrokeBlendMode mode) noexcept
{
switch (mode) {
case pp::paint::StrokeBlendMode::normal:
case pp::paint::StrokeBlendMode::multiply:
case pp::paint::StrokeBlendMode::subtract:
case pp::paint::StrokeBlendMode::darken:
case pp::paint::StrokeBlendMode::overlay:
case pp::paint::StrokeBlendMode::color_dodge:
case pp::paint::StrokeBlendMode::color_burn:
case pp::paint::StrokeBlendMode::linear_burn:
case pp::paint::StrokeBlendMode::hard_mix:
case pp::paint::StrokeBlendMode::linear_height:
case pp::paint::StrokeBlendMode::height:
return true;
}
return false;
}
[[nodiscard]] bool paint_blend_mode_from_persisted_index(int value, pp::paint::BlendMode& out) noexcept
{
switch (value) {
case 0: out = pp::paint::BlendMode::normal; return true;
case 1: out = pp::paint::BlendMode::multiply; return true;
case 2: out = pp::paint::BlendMode::screen; return true;
case 3: out = pp::paint::BlendMode::color_dodge; return true;
case 4: out = pp::paint::BlendMode::overlay; return true;
default: return false;
}
}
[[nodiscard]] bool stroke_blend_mode_from_persisted_index(int value, pp::paint::StrokeBlendMode& out) noexcept
{
switch (value) {
case 0: out = pp::paint::StrokeBlendMode::normal; return true;
case 1: out = pp::paint::StrokeBlendMode::multiply; return true;
case 2: out = pp::paint::StrokeBlendMode::subtract; return true;
case 3: out = pp::paint::StrokeBlendMode::darken; return true;
case 4: out = pp::paint::StrokeBlendMode::overlay; return true;
case 5: out = pp::paint::StrokeBlendMode::color_dodge; return true;
case 6: out = pp::paint::StrokeBlendMode::color_burn; return true;
case 7: out = pp::paint::StrokeBlendMode::linear_burn; return true;
case 8: out = pp::paint::StrokeBlendMode::hard_mix; return true;
case 9: out = pp::paint::StrokeBlendMode::linear_height; return true;
case 10: out = pp::paint::StrokeBlendMode::height; return true;
default: return false;
}
}
[[nodiscard]] pp::foundation::Result<std::size_t> expected_pixel_count(pp::renderer::Extent2D extent) noexcept
{
const auto extent_status = pp::renderer::validate_extent(extent);
if (!extent_status.ok()) {
return pp::foundation::Result<std::size_t>::failure(extent_status);
}
const auto width = static_cast<std::uint64_t>(extent.width);
const auto height = static_cast<std::uint64_t>(extent.height);
if (width > std::numeric_limits<std::uint64_t>::max() / height) {
return pp::foundation::Result<std::size_t>::failure(
pp::foundation::Status::out_of_range("pixel count overflows uint64"));
}
const auto count = width * height;
if (count > static_cast<std::uint64_t>(std::numeric_limits<std::size_t>::max())) {
return pp::foundation::Result<std::size_t>::failure(
pp::foundation::Status::out_of_range("pixel count exceeds addressable memory"));
}
return pp::foundation::Result<std::size_t>::success(static_cast<std::size_t>(count));
}
[[nodiscard]] StrokeCompositePath composite_path_from_feedback(pp::renderer::PaintFeedbackPath path) noexcept
{
switch (path) {
case pp::renderer::PaintFeedbackPath::none:
return StrokeCompositePath::fixed_function_blend;
case pp::renderer::PaintFeedbackPath::framebuffer_fetch:
return StrokeCompositePath::framebuffer_fetch;
case pp::renderer::PaintFeedbackPath::ping_pong_textures:
return StrokeCompositePath::ping_pong_textures;
}
return StrokeCompositePath::fixed_function_blend;
}
void apply_stroke_plan(CanvasBlendGatePlan& gate, const StrokeCompositePlan& stroke) noexcept
{
gate.path = stroke.path;
gate.reads_destination_color = stroke.reads_destination_color;
gate.requires_auxiliary_texture = stroke.requires_auxiliary_texture;
gate.requires_texture_copy = stroke.requires_texture_copy;
gate.requires_render_target_blit = stroke.requires_render_target_blit;
}
void mark_shader_blend_fallback(
CanvasBlendGatePlan& gate,
pp::renderer::RenderDeviceFeatures features) noexcept
{
gate.shader_blend = true;
gate.complex_blend = true;
gate.compatibility_fallback = true;
if (features.framebuffer_fetch) {
gate.path = StrokeCompositePath::framebuffer_fetch;
gate.reads_destination_color = true;
} else if (features.texture_copy || features.render_target_blit) {
gate.path = StrokeCompositePath::ping_pong_textures;
gate.requires_auxiliary_texture = true;
gate.requires_texture_copy = features.texture_copy;
gate.requires_render_target_blit = !features.texture_copy && features.render_target_blit;
}
}
}
pp::foundation::Status composite_layer(
std::span<pp::paint::Rgba> destination,
pp::renderer::Extent2D extent,
LayerCompositeView layer) noexcept
{
const auto pixel_count = expected_pixel_count(extent);
if (!pixel_count) {
return pixel_count.status();
}
if (destination.size() != pixel_count.value() || layer.pixels.size() != pixel_count.value()) {
return pp::foundation::Status::invalid_argument("composite buffers must match the render extent");
}
if (layer.opacity < 0.0F || layer.opacity > 1.0F) {
return pp::foundation::Status::out_of_range("layer opacity must be between 0 and 1");
}
if (!layer.visible || layer.opacity == 0.0F) {
return pp::foundation::Status::success();
}
for (std::size_t i = 0; i < destination.size(); ++i) {
auto stroke = layer.pixels[i];
stroke.a *= layer.opacity;
destination[i] = pp::paint::blend_pixels(destination[i], stroke, layer.blend_mode);
}
return pp::foundation::Status::success();
}
bool stroke_composite_requires_feedback(
pp::paint::BlendMode layer_blend_mode,
pp::paint::StrokeBlendMode stroke_blend_mode,
bool dual_brush_blend,
bool pattern_blend) noexcept
{
return layer_blend_mode != pp::paint::BlendMode::normal
|| stroke_blend_mode != pp::paint::StrokeBlendMode::normal
|| dual_brush_blend
|| pattern_blend;
}
pp::foundation::Result<StrokeCompositePlan> plan_stroke_composite(
pp::renderer::RenderDeviceFeatures features,
StrokeCompositeRequest request) noexcept
{
if (!is_valid_blend_mode(request.layer_blend_mode)) {
return pp::foundation::Result<StrokeCompositePlan>::failure(
pp::foundation::Status::invalid_argument("unknown layer blend mode"));
}
if (!is_valid_stroke_blend_mode(request.stroke_blend_mode)) {
return pp::foundation::Result<StrokeCompositePlan>::failure(
pp::foundation::Status::invalid_argument("unknown stroke blend mode"));
}
const pp::renderer::TextureDesc target_desc {
.extent = request.extent,
.format = request.target_format,
.usage = request.target_usage,
.debug_name = "stroke-composite-target",
};
const auto complex_blend = stroke_composite_requires_feedback(
request.layer_blend_mode,
request.stroke_blend_mode,
request.dual_brush_blend,
request.pattern_blend);
const auto feedback = pp::renderer::plan_paint_feedback(features, target_desc, complex_blend);
if (!feedback) {
return pp::foundation::Result<StrokeCompositePlan>::failure(feedback.status());
}
StrokeCompositePlan plan;
plan.path = composite_path_from_feedback(feedback.value().path);
plan.feedback = feedback.value();
plan.target_desc = target_desc;
plan.target_bytes = feedback.value().target_bytes;
plan.auxiliary_bytes = feedback.value().requires_auxiliary_texture
? feedback.value().target_bytes
: 0U;
plan.estimated_working_bytes = plan.target_bytes + plan.auxiliary_bytes;
plan.complex_blend = complex_blend;
plan.reads_destination_color = feedback.value().reads_destination_color;
plan.requires_auxiliary_texture = feedback.value().requires_auxiliary_texture;
plan.requires_texture_copy = feedback.value().requires_texture_copy;
plan.requires_render_target_blit = feedback.value().requires_render_target_blit;
plan.requires_explicit_transition = feedback.value().requires_explicit_transition;
return pp::foundation::Result<StrokeCompositePlan>::success(plan);
}
pp::foundation::Result<CanvasBlendGatePlan> plan_canvas_blend_gate(
pp::renderer::RenderDeviceFeatures features,
CanvasBlendGateRequest request) noexcept
{
CanvasBlendGatePlan gate;
for (std::size_t i = 0; i < request.layer_blend_modes.size(); ++i) {
pp::paint::BlendMode layer_blend = pp::paint::BlendMode::normal;
if (!paint_blend_mode_from_persisted_index(request.layer_blend_modes[i], layer_blend)) {
if (request.layer_blend_modes[i] != 0) {
gate.first_complex_layer_index = static_cast<int>(i);
mark_shader_blend_fallback(gate, features);
return pp::foundation::Result<CanvasBlendGatePlan>::success(gate);
}
continue;
}
if (layer_blend == pp::paint::BlendMode::normal) {
continue;
}
gate.shader_blend = true;
gate.complex_blend = true;
gate.first_complex_layer_index = static_cast<int>(i);
const auto stroke = plan_stroke_composite(
features,
StrokeCompositeRequest {
.extent = request.extent,
.layer_blend_mode = layer_blend,
});
if (stroke) {
apply_stroke_plan(gate, stroke.value());
} else {
gate.compatibility_fallback = true;
}
return pp::foundation::Result<CanvasBlendGatePlan>::success(gate);
}
pp::paint::StrokeBlendMode stroke_blend = pp::paint::StrokeBlendMode::normal;
if (request.has_stroke_blend_mode) {
if (!stroke_blend_mode_from_persisted_index(request.stroke_blend_mode, stroke_blend)) {
if (request.stroke_blend_mode != 0) {
gate.stroke_complex = true;
mark_shader_blend_fallback(gate, features);
return pp::foundation::Result<CanvasBlendGatePlan>::success(gate);
}
} else if (stroke_blend != pp::paint::StrokeBlendMode::normal) {
gate.stroke_complex = true;
}
}
gate.dual_brush_complex = request.dual_brush_blend;
gate.pattern_complex = request.pattern_blend;
if (!gate.stroke_complex && !gate.dual_brush_complex && !gate.pattern_complex) {
return pp::foundation::Result<CanvasBlendGatePlan>::success(gate);
}
gate.shader_blend = true;
gate.complex_blend = true;
const auto stroke = plan_stroke_composite(
features,
StrokeCompositeRequest {
.extent = request.extent,
.stroke_blend_mode = stroke_blend,
.dual_brush_blend = request.dual_brush_blend,
.pattern_blend = request.pattern_blend,
});
if (stroke) {
apply_stroke_plan(gate, stroke.value());
} else {
gate.compatibility_fallback = true;
}
return pp::foundation::Result<CanvasBlendGatePlan>::success(gate);
}
const char* stroke_composite_path_name(StrokeCompositePath path) noexcept
{
switch (path) {
case StrokeCompositePath::fixed_function_blend:
return "fixed_function_blend";
case StrokeCompositePath::framebuffer_fetch:
return "framebuffer_fetch";
case StrokeCompositePath::ping_pong_textures:
return "ping_pong_textures";
}
return "unknown";
}
}