RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-25 19:37:35 +00:00
Code Issues Activity Actions

LibAccelGfx: Premultiply linear gradient colors by alpha

Browse source 
With this change color blending for gradients matches CPU painter.
This commit is contained in:
Aliaksandr Kalenik 2023-11-29 12:53:49 +01:00 • committed by Andreas Kling
parent be8952b89d
commit 707added91
3 changed files with 37 additions and 16 deletions
Download patch file Download diff file Expand all files Collapse all files

28
Userland/Libraries/LibAccelGfx/Painter.cpp
View file

@ -205,7 +205,7 @@ void Painter::fill_rect(Gfx::FloatRect rect, Gfx::Color color)
GL::set_uniform(color_uniform, red, green, blue, alpha);
GL::set_vertex_attribute(position_attribute, 0, 2);
GL::enable_blending();
GL::enable_blending(GL::BlendFactor::SrcAlpha, GL::BlendFactor::OneMinusSrcAlpha);
GL::draw_arrays(GL::DrawPrimitive::TriangleFan, 4);
GL::delete_buffer(vbo);
@ -254,7 +254,7 @@ void Painter::fill_rect_with_rounded_corners(Gfx::FloatRect const& rect, Color c
auto bottom_right_corner_radius_uniform = m_rounded_rectangle_program.get_uniform_location("uBottomRightRadius");
GL::set_uniform(bottom_right_corner_radius_uniform, bottom_right_radius.horizontal_radius, bottom_right_radius.vertical_radius);
GL::enable_blending();
GL::enable_blending(GL::BlendFactor::SrcAlpha, GL::BlendFactor::OneMinusSrcAlpha);
GL::draw_arrays(GL::DrawPrimitive::TriangleFan, 4);
GL::delete_buffer(vbo);
@ -297,7 +297,7 @@ void Painter::draw_line(Gfx::FloatPoint a, Gfx::FloatPoint b, float thickness, C
GL::set_uniform(color_uniform, red, green, blue, alpha);
GL::set_vertex_attribute(position_attribute, 0, 2);
GL::enable_blending();
GL::enable_blending(GL::BlendFactor::SrcAlpha, GL::BlendFactor::OneMinusSrcAlpha);
GL::draw_arrays(GL::DrawPrimitive::TriangleFan, 4);
GL::delete_buffer(vbo);
@ -438,6 +438,7 @@ void Painter::draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Col
GL::set_uniform(color_uniform, red, green, blue, alpha);
GL::set_vertex_attribute(position_attribute, 0, 4);
GL::enable_blending(GL::BlendFactor::SrcAlpha, GL::BlendFactor::OneMinusSrcAlpha);
GL::draw_arrays(GL::DrawPrimitive::Triangles, vertices.size() / 4);
GL::delete_buffer(vbo);
@ -491,23 +492,23 @@ void Painter::fill_rect_with_linear_gradient(Gfx::FloatRect const& rect, Readonl
auto add_triangle = [&](auto& p1, auto& p2, auto& p3, auto& c1, auto& c2, auto& c3) {
vertices.append(p1.x());
vertices.append(p1.y());
colors.append(c1.red);
colors.append(c1.green);
colors.append(c1.blue);
colors.append(c1.red * c1.alpha);
colors.append(c1.green * c1.alpha);
colors.append(c1.blue * c1.alpha);
colors.append(c1.alpha);
vertices.append(p2.x());
vertices.append(p2.y());
colors.append(c2.red);
colors.append(c2.green);
colors.append(c2.blue);
colors.append(c2.red * c2.alpha);
colors.append(c2.green * c2.alpha);
colors.append(c2.blue * c2.alpha);
colors.append(c2.alpha);
vertices.append(p3.x());
vertices.append(p3.y());
colors.append(c3.red);
colors.append(c3.green);
colors.append(c3.blue);
colors.append(c3.red * c3.alpha);
colors.append(c3.green * c3.alpha);
colors.append(c3.blue * c3.alpha);
colors.append(c3.alpha);
};
@ -534,6 +535,7 @@ void Painter::fill_rect_with_linear_gradient(Gfx::FloatRect const& rect, Readonl
GL::bind_buffer(vbo_colors);
GL::set_vertex_attribute(color_attribute, 0, 4);
GL::enable_blending(GL::BlendFactor::One, GL::BlendFactor::OneMinusSrcAlpha);
GL::draw_arrays(GL::DrawPrimitive::Triangles, vertices.size() / 2);
}
@ -633,7 +635,7 @@ void Painter::blit_scaled_texture(Gfx::FloatRect const& dst_rect, GL::Texture co
auto scaling_mode_gl = to_gl_scaling_mode(scaling_mode);
GL::set_texture_scale_mode(scaling_mode_gl);
GL::enable_blending();
GL::enable_blending(GL::BlendFactor::SrcAlpha, GL::BlendFactor::OneMinusSrcAlpha);
GL::draw_arrays(GL::DrawPrimitive::TriangleFan, 4);