LibAccelGfx: Remove ability to change target canvas in painter

It is easier to build painter assuming target canvas won't change and
we don't use this api anyway :)

Userland/Libraries/LibAccelGfx/Painter.cpp

@@ -170,13 +170,14 @@ void main() {
 
 HashMap<u32, GL::Texture> s_immutable_bitmap_texture_cache;
 
-NonnullOwnPtr<Painter> Painter::create(Context& context)
+NonnullOwnPtr<Painter> Painter::create(Context& context, NonnullRefPtr<Canvas> canvas)
 {
-    return make<Painter>(context);
+    return make<Painter>(context, canvas);
 }
 
-Painter::Painter(Context& context)
+Painter::Painter(Context& context, NonnullRefPtr<Canvas> canvas)
     : m_context(context)
+    , m_target_canvas(canvas)
     , m_rectangle_program(Program::create(Program::Name::RectangleProgram, vertex_shader_source, solid_color_fragment_shader_source))
     , m_rounded_rectangle_program(Program::create(Program::Name::RoundedRectangleProgram, vertex_shader_source, rect_with_rounded_corners_fragment_shader_source))
     , m_blit_program(Program::create(Program::Name::BlitProgram, blit_vertex_shader_source, blit_fragment_shader_source))
@@ -184,6 +185,8 @@ Painter::Painter(Context& context)
     , m_blur_program(Program::create(Program::Name::BlurProgram, blit_vertex_shader_source, blur_fragment_shader_source))
 {
     m_state_stack.empend(State());
+    state().clip_rect = { { 0, 0 }, m_target_canvas->size() };
+    bind_target_canvas();
 }
 
 Painter::~Painter()
@@ -607,14 +610,6 @@ void Painter::bind_target_canvas()
     GL::enable_scissor_test(state().clip_rect);
 }
 
-void Painter::set_target_canvas(NonnullRefPtr<Canvas> canvas)
-{
-    m_target_canvas = canvas;
-    canvas->bind();
-    GL::set_viewport({ 0, 0, canvas->size().width(), canvas->size().height() });
-    state().clip_rect = { { 0, 0 }, m_target_canvas->size() };
-}
-
 void Painter::flush(Gfx::Bitmap& bitmap)
 {
     m_target_canvas->bind();

Userland/Libraries/LibAccelGfx/Painter.h

@@ -29,9 +29,9 @@ class Painter {
     AK_MAKE_NONMOVABLE(Painter);
 
 public:
-    static NonnullOwnPtr<Painter> create(Context&);
+    static NonnullOwnPtr<Painter> create(Context&, NonnullRefPtr<Canvas>);
 
-    Painter(Context&);
+    Painter(Context&, NonnullRefPtr<Canvas>);
     ~Painter();
 
     void clear(Gfx::Color);
@@ -67,7 +67,6 @@ public:
     void set_clip_rect(Gfx::IntRect);
     void clear_clip_rect();
 
-    void set_target_canvas(NonnullRefPtr<Canvas>);
     void flush(Gfx::Bitmap&);
 
     void fill_rect_with_linear_gradient(Gfx::IntRect const&, ReadonlySpan<Gfx::ColorStop>, float angle, Optional<float> repeat_length = {});
@@ -110,7 +109,7 @@ private:
 
     Vector<State, 1> m_state_stack;
 
-    RefPtr<Canvas> m_target_canvas;
+    NonnullRefPtr<Canvas> m_target_canvas;
 
     Program m_rectangle_program;
     Program m_rounded_rectangle_program;

Userland/Libraries/LibWeb/Painting/PaintingCommandExecutorGPU.cpp

@@ -13,9 +13,8 @@ PaintingCommandExecutorGPU::PaintingCommandExecutorGPU(AccelGfx::Context& contex
     : m_target_bitmap(bitmap)
     , m_context(context)
 {
-    auto painter = AccelGfx::Painter::create(m_context);
     auto canvas = AccelGfx::Canvas::create(bitmap.size());
-    painter->set_target_canvas(canvas);
+    auto painter = AccelGfx::Painter::create(m_context, canvas);
     m_stacking_contexts.append({ .canvas = canvas,
         .painter = move(painter),
         .opacity = 1.0f,
@@ -115,9 +114,8 @@ CommandResult PaintingCommandExecutorGPU::push_stacking_context(float opacity, b
     final_transform.multiply(stacking_context_transform);
     final_transform.multiply(inverse_origin_translation);
     if (opacity < 1 || !stacking_context_transform.is_identity_or_translation()) {
-        auto painter = AccelGfx::Painter::create(m_context);
         auto canvas = AccelGfx::Canvas::create(source_paintable_rect.size());
-        painter->set_target_canvas(canvas);
+        auto painter = AccelGfx::Painter::create(m_context, canvas);
         painter->translate(-source_paintable_rect.location().to_type<float>());
         painter->clear(Color::Transparent);
         m_stacking_contexts.append({ .canvas = canvas,
@@ -169,8 +167,7 @@ CommandResult PaintingCommandExecutorGPU::paint_inner_box_shadow(PaintOuterBoxSh
 CommandResult PaintingCommandExecutorGPU::paint_text_shadow(int blur_radius, Gfx::IntRect const& shadow_bounding_rect, Gfx::IntRect const& text_rect, Span<Gfx::DrawGlyphOrEmoji const> glyph_run, Color const& color, int fragment_baseline, Gfx::IntPoint const& draw_location)
 {
     auto text_shadow_canvas = AccelGfx::Canvas::create(shadow_bounding_rect.size());
-    auto text_shadow_painter = AccelGfx::Painter::create(m_context);
+    auto text_shadow_painter = AccelGfx::Painter::create(m_context, text_shadow_canvas);
-    text_shadow_painter->set_target_canvas(text_shadow_canvas);
     text_shadow_painter->clear(color.with_alpha(0));
 
     Gfx::FloatRect const shadow_location { draw_location, shadow_bounding_rect.size() };
@@ -183,8 +180,7 @@ CommandResult PaintingCommandExecutorGPU::paint_text_shadow(int blur_radius, Gfx
     }
 
     auto horizontal_blur_canvas = AccelGfx::Canvas::create(shadow_bounding_rect.size());
-    auto horizontal_blur_painter = AccelGfx::Painter::create(m_context);
+    auto horizontal_blur_painter = AccelGfx::Painter::create(m_context, horizontal_blur_canvas);
-    horizontal_blur_painter->set_target_canvas(horizontal_blur_canvas);
     horizontal_blur_painter->clear(color.with_alpha(0));
     horizontal_blur_painter->blit_blurred_canvas(shadow_bounding_rect.to_type<float>(), *text_shadow_canvas, blur_radius, AccelGfx::Painter::BlurDirection::Horizontal);
     painter().blit_blurred_canvas(shadow_location, *horizontal_blur_canvas, blur_radius, AccelGfx::Painter::BlurDirection::Vertical);