feat(webgl): Migrate to pure WebGL 2.0 and fix GL canvas layering

Update submodules and build config for pure WebGL 2.0 (drop -sFULL_ES3):
- kicad: VBO-based drawing, compositor FBO rewrite, shader conversion
- wxwidgets: Fix z-index layering so GL canvas renders above 2D UI canvas
- Build: Remove FULL_ES3 from linker flags
- GAL tests: White background, opaque alpha, shared shader converter,
  updated baseline screenshots

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

kicad

@@ -1 +1 @@
-Subproject commit d8a9ac4304f5747be43e88deca7bfa0ac87c0213
+Subproject commit 4ddb9b47f5f9dc3f30ed6d59778e7bc407fdc3cd

scripts/kicad/build-pcbnew.sh

@@ -243,7 +243,7 @@ emcmake cmake "${KICAD_DIR}" \
     -DCMAKE_POLICY_VERSION_MINIMUM=3.5 \
     -DCMAKE_CXX_FLAGS="${EXTRA_FLAGS} -pthread -sUSE_ZLIB=1 -DKICAD_USE_PLATFORM_WASM=1 -I${SYSROOT}/include -I${STUBS_DIR}" \
     -DCMAKE_C_FLAGS="${EXTRA_FLAGS} -pthread -sUSE_ZLIB=1 -I${SYSROOT}/include -I${STUBS_DIR}" \
-    -DCMAKE_EXE_LINKER_FLAGS="${LINKER_DEBUG_FLAGS} -pthread -sUSE_ZLIB=1 -sASYNCIFY=1 -sDYNCALLS=1 -sASYNCIFY_STACK_SIZE=65536 -sUSE_PTHREADS=1 -sPTHREAD_POOL_SIZE='navigator.hardwareConcurrency' -sPTHREAD_POOL_SIZE_STRICT=0 -sALLOW_MEMORY_GROWTH=1 -sINITIAL_MEMORY=256MB -sMAXIMUM_MEMORY=4GB -sMAX_WEBGL_VERSION=2 -sFULL_ES3=1 -sEXPORTED_RUNTIME_METHODS=['ccall','cwrap','UTF8ToString','stringToUTF8','lengthBytesUTF8','dynCall'] -sDEFAULT_LIBRARY_FUNCS_TO_INCLUDE=['\$dynCall'] --bind -L${SYSROOT}/lib ${STUBS_BUILD}/libgit2_stub.a ${STUBS_BUILD}/libcurl_stub.a ${STUBS_BUILD}/libpcbnew_scripting_stub.a ${STUBS_BUILD}/libnng_stub.a ${STUBS_BUILD}/pcbnew_embind.o" \
+    -DCMAKE_EXE_LINKER_FLAGS="${LINKER_DEBUG_FLAGS} -pthread -sUSE_ZLIB=1 -sASYNCIFY=1 -sDYNCALLS=1 -sASYNCIFY_STACK_SIZE=65536 -sUSE_PTHREADS=1 -sPTHREAD_POOL_SIZE='navigator.hardwareConcurrency' -sPTHREAD_POOL_SIZE_STRICT=0 -sALLOW_MEMORY_GROWTH=1 -sINITIAL_MEMORY=256MB -sMAXIMUM_MEMORY=4GB -sMAX_WEBGL_VERSION=2 -sEXPORTED_RUNTIME_METHODS=['ccall','cwrap','UTF8ToString','stringToUTF8','lengthBytesUTF8','dynCall'] -sDEFAULT_LIBRARY_FUNCS_TO_INCLUDE=['\$dynCall'] --bind -L${SYSROOT}/lib ${STUBS_BUILD}/libgit2_stub.a ${STUBS_BUILD}/libcurl_stub.a ${STUBS_BUILD}/libpcbnew_scripting_stub.a ${STUBS_BUILD}/libnng_stub.a ${STUBS_BUILD}/pcbnew_embind.o" \
     -DCMAKE_PREFIX_PATH="${SYSROOT};${WX_BUILD}" \
     -DwxWidgets_CONFIG_EXECUTABLE="${WX_BUILD}/wx-config" \
     \

tests/gal-regression/native/gal_native_test.cpp

@@ -97,6 +97,15 @@ bool SaveScreenshot(const std::string& path, KIGFX::OPENGL_GAL* gal, int width,
     if (hasContent) std::cout << " (" << nonBlackCount << " non-black pixels)";
     std::cout << std::endl;
 
+    // Force all alpha values to 255 (opaque) to match the composited canvas output.
+    // Native reads from the FBO where alpha < 255 for semi-transparent regions.
+    // WebGL captures the composited canvas where alpha is always 1.0 (composited on
+    // black with GL_ONE blend). By making native output opaque, both tests produce
+    // equivalent "user-visible" screenshots that can be compared directly.
+    for (size_t i = 3; i < pixels.size(); i += 4) {
+        pixels[i] = 255;
+    }
+
     // Flip vertically (OpenGL has origin at bottom-left)
     stbi_flip_vertically_on_write(1);
 
@@ -173,7 +182,11 @@ public:
 
         // Set up the viewport - use ResizeScreen to properly initialize compositor
         m_gal->ResizeScreen(g_width, g_height);
-        m_gal->SetClearColor(KIGFX::COLOR4D(0.1, 0.1, 0.15, 1.0));
+        // Use white background to match WebGL test (which captures the composited canvas).
+        // Native reads from the FBO (pre-compositing), so we set alpha to 255 in SaveScreenshot
+        // to simulate the composited result. White background ensures both tests see the same
+        // blended colors for semi-transparent shapes.
+        m_gal->SetClearColor(KIGFX::COLOR4D(1.0, 1.0, 1.0, 1.0));
 
         // CRITICAL: Set worldUnitLength for 1:1 world-to-screen coordinate mapping
         // GAL default worldUnitLength is for PCB nanometers (3.937e-8), which would

tests/gal-regression/wasm/Makefile

@@ -69,11 +69,11 @@ BASE_LDFLAGS = -sALLOW_MEMORY_GROWTH=1 \
                -sEXPORTED_RUNTIME_METHODS=['ccall','cwrap','HEAPU8'] \
                -sMODULARIZE=1 \
                -sEXPORT_NAME='createGALTest' \
-               -sENVIRONMENT=web
+               -sENVIRONMENT=web,worker
 
-# GL-specific flags - WebGL 2.0 with full ES3 support
+# GL-specific flags - pure WebGL 2.0 (matching KiCad PCBnew build, no FULL_ES3 emulation)
 # No LEGACY_GL_EMULATION - WEBGL_GAL uses VBOs and custom shaders
-EM_GL_FLAGS = -sFULL_ES3=1 -sMAX_WEBGL_VERSION=2
+EM_GL_FLAGS = -sMAX_WEBGL_VERSION=2
 
 # Legacy GL stubs for wxWidgets compatibility
 # wxWidgets GL library may reference legacy functions at runtime, but actual

tests/gal-regression/wasm/generate_shaders.py

@@ -9,191 +9,14 @@ KiCad's BUILTIN_SHADERS namespace.
 import os
 import sys
 
-import re
-
-def convert_glsl120_to_es300(shader_source, is_fragment_shader):
-    """
-    Convert GLSL 1.20 (OpenGL 2.1) shader to GLSL ES 3.00 (WebGL 2.0).
-
-    Key changes:
-    - #version 120 -> #version 300 es (must be ABSOLUTE first line!)
-    - Move any comments before #version to after declarations
-    - Add precision qualifiers
-    - attribute -> in
-    - varying -> out (vertex) / in (fragment)
-    - gl_FragColor -> custom output variable (fragment)
-    - texture2D -> texture
-    - Fix int * float type issues (2 * x -> 2.0 * x)
-    - Fix int / float type issues (x / 4 -> x / 4.0)
-
-    Legacy GL built-in conversions (for KiCad shaders):
-    - gl_ModelViewProjectionMatrix -> uniform u_modelViewProjectionMatrix
-    - gl_Vertex -> attribute a_vertex
-    - gl_Color -> attribute a_color (vertex) / varying v_color (fragment)
-    - gl_FrontColor -> varying v_color (vertex output)
-    - gl_TexCoord[0] -> varying v_texCoord
-    - ftransform() -> u_modelViewProjectionMatrix * a_vertex
-    """
-    lines = shader_source.split('\n')
-    result = []
-    version_replaced = False
-
-    # Track what legacy built-ins are used so we can add declarations
-    uses_mvp_matrix = 'gl_ModelViewProjectionMatrix' in shader_source or 'ftransform()' in shader_source
-    uses_gl_vertex = 'gl_Vertex' in shader_source or 'ftransform()' in shader_source
-    uses_gl_color = 'gl_Color' in shader_source
-    uses_gl_front_color = 'gl_FrontColor' in shader_source
-    uses_gl_texcoord = 'gl_TexCoord' in shader_source
-    uses_gl_multitexcoord0 = 'gl_MultiTexCoord0' in shader_source
-
-    # GLSL ES 3.00 requires #version to be the ABSOLUTE first line
-    # Collect any comments before #version to add after declarations
-    pre_version_comments = []
-    in_multiline_comment = False
-
-    # Patterns to fix type issues
-    int_mult_pattern = re.compile(r'\b(\d+)\s*\*\s*([a-zA-Z_])')
-    div_int_pattern = re.compile(r'([a-zA-Z_)\]]+)\s*/\s*(\d+)(?!\.)')
-
-    for line in lines:
-        stripped = line.strip()
-
-        # Before #version is found, collect comments and empty lines
-        if not version_replaced:
-            # Track multiline comment state
-            if '/*' in stripped and '*/' not in stripped:
-                in_multiline_comment = True
-                pre_version_comments.append(line)
-                continue
-            elif in_multiline_comment:
-                pre_version_comments.append(line)
-                if '*/' in stripped:
-                    in_multiline_comment = False
-                continue
-            elif stripped.startswith('//') or stripped == '' or ('/*' in stripped and '*/' in stripped):
-                pre_version_comments.append(line)
-                continue
-
-        # Replace #version 120 with #version 300 es + precision + legacy built-in replacements
-        if stripped.startswith('#version'):
-            result.append('#version 300 es')
-            result.append('precision highp float;')
-            result.append('precision highp int;')
-
-            if is_fragment_shader:
-                result.append('out vec4 fragColor;')
-                # Fragment shader receives varyings from vertex shader
-                if uses_gl_color or uses_gl_front_color:
-                    result.append('in vec4 v_color;')
-                if uses_gl_texcoord:
-                    result.append('in vec2 v_texCoord;')
-            else:
-                # Vertex shader - add uniforms and attributes for legacy built-ins
-                if uses_mvp_matrix:
-                    result.append('uniform mat4 u_modelViewProjectionMatrix;')
-                if uses_gl_vertex:
-                    result.append('in vec4 a_vertex;')
-                if uses_gl_color:
-                    result.append('in vec4 a_color;')
-                if uses_gl_multitexcoord0:
-                    result.append('in vec4 a_texCoord0;')
-                # Vertex shader outputs varyings
-                if uses_gl_front_color or uses_gl_color:
-                    result.append('out vec4 v_color;')
-                if uses_gl_texcoord:
-                    result.append('out vec2 v_texCoord;')
-
-            # Add back any pre-version comments after the declarations
-            if pre_version_comments:
-                result.append('')  # Blank line before comments
-                result.extend(pre_version_comments)
-
-            version_replaced = True
-            continue
-
-        # Convert attribute to in (vertex shaders only)
-        if not is_fragment_shader and stripped.startswith('attribute '):
-            line = line.replace('attribute ', 'in ', 1)
-
-        # Convert varying to out (vertex) or in (fragment)
-        if stripped.startswith('varying '):
-            if is_fragment_shader:
-                line = line.replace('varying ', 'in ', 1)
-            else:
-                line = line.replace('varying ', 'out ', 1)
-
-        # Convert gl_FragColor to fragColor (fragment shaders)
-        if is_fragment_shader and 'gl_FragColor' in line:
-            line = line.replace('gl_FragColor', 'fragColor')
-
-        # Convert texture2D to texture
-        if 'texture2D' in line:
-            line = line.replace('texture2D', 'texture')
-
-        # Convert legacy GL built-ins
-        # ftransform() -> u_modelViewProjectionMatrix * a_vertex (must be done before other replacements)
-        if 'ftransform()' in line:
-            line = line.replace('ftransform()', 'u_modelViewProjectionMatrix * a_vertex')
-
-        # gl_ModelViewProjectionMatrix -> u_modelViewProjectionMatrix
-        if 'gl_ModelViewProjectionMatrix' in line:
-            line = line.replace('gl_ModelViewProjectionMatrix', 'u_modelViewProjectionMatrix')
-
-        # gl_Vertex -> a_vertex
-        if 'gl_Vertex' in line:
-            line = line.replace('gl_Vertex', 'a_vertex')
-
-        # gl_FrontColor -> v_color (vertex shader output)
-        if 'gl_FrontColor' in line:
-            line = line.replace('gl_FrontColor', 'v_color')
-
-        # gl_Color -> a_color (vertex) or v_color (fragment)
-        if 'gl_Color' in line:
-            if is_fragment_shader:
-                line = line.replace('gl_Color', 'v_color')
-            else:
-                line = line.replace('gl_Color', 'a_color')
-
-        # gl_TexCoord[0].st or gl_TexCoord[0].xy -> v_texCoord
-        if 'gl_TexCoord' in line:
-            # Handle gl_TexCoord[0].st and gl_TexCoord[0].xy
-            line = re.sub(r'gl_TexCoord\[0\]\.st', 'v_texCoord', line)
-            line = re.sub(r'gl_TexCoord\[0\]\.xy', 'v_texCoord', line)
-            # Handle bare gl_TexCoord[0] (less common)
-            line = re.sub(r'gl_TexCoord\[0\]', 'vec4(v_texCoord, 0.0, 0.0)', line)
-
-        # gl_MultiTexCoord0 -> a_texCoord0 (for SMAA shaders)
-        if 'gl_MultiTexCoord0' in line:
-            line = re.sub(r'gl_MultiTexCoord0\.st', 'a_texCoord0.st', line)
-            line = re.sub(r'gl_MultiTexCoord0\.xy', 'a_texCoord0.xy', line)
-            line = line.replace('gl_MultiTexCoord0', 'a_texCoord0')
-
-        # Fix uniform int -> uniform float (GLSL ES 3.00 doesn't allow implicit int/float conversion)
-        # This specifically handles u_fontTextureWidth which is multiplied with floats
-        if 'uniform int ' in line:
-            line = line.replace('uniform int ', 'uniform float ')
-
-        # Fix int * float type issues: "2 * x" -> "2.0 * x"
-        def fix_int_mult(match):
-            int_val = match.group(1)
-            var_start = match.group(2)
-            return f'{int_val}.0 * {var_start}'
-        line = int_mult_pattern.sub(fix_int_mult, line)
-
-        # Fix float / int type issues: "x / 4" -> "x / 4.0"
-        def fix_div_int(match):
-            var_part = match.group(1)
-            int_val = match.group(2)
-            return f'{var_part} / {int_val}.0'
-        line = div_int_pattern.sub(fix_div_int, line)
-
-        result.append(line)
-
-    # If no #version was found, DON'T add one - the shader will get its version
-    # from a runtime preamble (e.g. SMAA shaders). Just do basic conversions.
-    # NOTE: If the shader has no #version, we still need to convert legacy GL built-ins
-
-    return '\n'.join(result)
+# Import the canonical GLSL converter from the KiCad shaders directory.
+# This ensures the test uses the exact same conversion as the KiCad WASM build.
+_kicad_shaders_dir = os.path.join(
+    os.path.dirname(os.path.abspath(__file__)),
+    '..', '..', '..', 'kicad', 'common', 'gal', 'shaders'
+)
+sys.path.insert(0, os.path.abspath(_kicad_shaders_dir))
+from convert_glsl_es3 import convert_glsl120_to_es300
 
 
 def convert_shader_to_cpp(source_path, var_name):

wxwidgets

@@ -1 +1 @@
-Subproject commit c5aaa19ca9cffe739d9ccbc99003bc712eda031e
+Subproject commit 915a2ac4d87afc7dbd8005dab3238cb9bbd0a52c