Raspberry Pi: Adapting libgui for OpenGL ES 2.0

Disabling features not available in GLES2.
skyjake · Mar 5, 2020 · ee23c88 · ee23c88
1 parent f9199b3
commit ee23c88
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Showing 7 changed files with 70 additions and 48 deletions.
diff --git a/doomsday/libs/gui/include/de/graphics/glinfo.h b/doomsday/libs/gui/include/de/graphics/glinfo.h
@@ -51,6 +51,9 @@ class LIBGUI_PUBLIC GLInfo
         duint32 EXT_texture_compression_s3tc : 1;
         duint32 EXT_texture_filter_anisotropic : 1;
 
+        // OpenGL ES extensions:
+        duint32 OES_rgb8_rgba8 : 1;
+
         // Vendor-specific extensions:
         duint32 NV_framebuffer_multisample_coverage : 1;
         duint32 NV_texture_barrier : 1;

diff --git a/doomsday/libs/gui/include/de/graphics/gltimer.h b/doomsday/libs/gui/include/de/graphics/gltimer.h
@@ -16,8 +16,7 @@
  * http://www.gnu.org/licenses</small>
  */
 
-#ifndef LIBGUI_GLTIMER_H
-#define LIBGUI_GLTIMER_H
+#pragma once
 
 #include <de/Id>
 #include "de/libgui.h"
@@ -72,5 +71,3 @@ class LIBGUI_PUBLIC GLTimer
 };
 
 } // namespace de
-
-#endif // LIBGUI_GLTIMER_H
diff --git a/doomsday/libs/gui/include/de/graphics/opengl.h b/doomsday/libs/gui/include/de/graphics/opengl.h
@@ -39,6 +39,7 @@ using namespace gl33core;
 
 #elif (DE_OPENGL_ES == 20)
 #  include <SDL_opengles2.h>
+#  include <GLES2/gl2ext.h>
 #endif
 
 // Defined in GLES2.

diff --git a/doomsday/libs/gui/src/graphics/glframebuffer.cpp b/doomsday/libs/gui/src/graphics/glframebuffer.cpp
@@ -39,6 +39,12 @@ static const int    MAX_COLOR_ATTACHMENTS = 4;
 static const int    MAX_COLOR_ATTACHMENTS = 1;
 #endif
 
+#if (DE_OPENGL_ES == 20)
+#  define GL_DRAW_FRAMEBUFFER   GL_FRAMEBUFFER
+#  define GL_READ_FRAMEBUFFER   GL_FRAMEBUFFER
+#  define GL_RGBA8              GL_RGBA8_OES
+#endif
+
 DE_PIMPL(GLFramebuffer)
 , DE_OBSERVES(Asset, Deletion)
 {
@@ -253,7 +259,11 @@ DE_PIMPL(GLFramebuffer)
         DE_ASSERT(tex.isReady());
         if (tex.isCubeMap())
         {
-            glFramebufferTexture(FRAMEBUFFER_GL, attachment, tex.glName(), level);
+#if defined (DE_OPENGL)
+            glFramebufferTexture(GL_FRAMEBUFFER, attachment, tex.glName(), level);
+#else
+            DE_ASSERT_FAIL("Cannot attach cube map texture to framebuffer");
+#endif            
         }
         else
         {
@@ -273,7 +283,7 @@ DE_PIMPL(GLFramebuffer)
         glBindRenderbuffer(GL_RENDERBUFFER, renderBufs[id]);
         LIBGUI_ASSERT_GL_OK();
 
-#if !defined(DE_OPENGL_ES)
+#if !defined (DE_OPENGL_ES)
         if (sampleCount > 1)
         {
             if (GLInfo::extensions().NV_framebuffer_multisample_coverage)
@@ -342,11 +352,13 @@ DE_PIMPL(GLFramebuffer)
     void allocRenderBuffers()
     {
         DE_ASSERT(size != nullSize);
-
+        
         // Fill in all the other requested attachments.
         if (flags.testFlag(Color0) && !textureAttachment.testFlag(Color0))
         {
-            /// @todo Note that for GLES, GL_RGBA8 is not supported (without an extension).
+#if defined (DE_OPENGL_ES)
+            DE_ASSERT(GLInfo::extensions().OES_rgb8_rgba8);
+#endif
             LOG_GL_VERBOSE("FBO %i: color renderbuffer %s") << fbo << size.asText();
             attachRenderbuffer(ColorBuffer0, GL_RGBA8, GL_COLOR_ATTACHMENT0);
         }
@@ -356,9 +368,9 @@ DE_PIMPL(GLFramebuffer)
         glBindRenderbuffer(GL_RENDERBUFFER, 0);
     }
 
-#if defined (DE_HAVE_DEPTH_STENCIL_ATTACHMENT)
     void allocDepthStencilRenderBuffers()
     {
+#if defined (DE_HAVE_DEPTH_STENCIL_ATTACHMENT)
         if (flags.testFlag(DepthStencil) && !flags.testFlag(SeparateDepthAndStencil) &&
             (!texture || textureAttachment == Color0))
         {
@@ -367,23 +379,21 @@ DE_PIMPL(GLFramebuffer)
             attachRenderbuffer(DepthStencilBuffer, GL_DEPTH24_STENCIL8, GL_DEPTH_STENCIL_ATTACHMENT);
         }
         else
+#endif // DE_HAVE_DEPTH_STENCIL_ATTACHMENT
         {
             // Separate depth and stencil, then.
             if (flags.testFlag(Depth) && !textureAttachment.testFlag(Depth))
             {
                 LOG_GL_VERBOSE("FBO %i: depth renderbuffer %s") << fbo << size.asText();
                 attachRenderbuffer(DepthBuffer, GL_DEPTH_COMPONENT, GL_DEPTH_ATTACHMENT);
             }
-#if defined (DE_OPENGL)
             if (flags.testFlag(Stencil) && !textureAttachment.testFlag(Stencil))
             {
                 LOG_GL_VERBOSE("FBO %i: stencil renderbuffer %s") << fbo << size.asText();
                 attachRenderbuffer(StencilBuffer, GL_STENCIL_INDEX, GL_STENCIL_ATTACHMENT);
             }
-#endif
         }
     }
-#endif // DE_HAVE_DEPTH_STENCIL_ATTACHMENT
 
     void deallocRenderBuffers()
     {
@@ -479,28 +489,31 @@ DE_PIMPL(GLFramebuffer)
     {
         DE_ASSERT(fbo);
 
-        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo); LIBGUI_ASSERT_GL_OK();
-//        glBindFramebuffer(GL_READ_FRAMEBUFFER, fbo); LIBGUI_ASSERT_GL_OK();
+        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
+        LIBGUI_ASSERT_GL_OK();
 
+#if defined (DE_HAVE_COLOR_ATTACHMENTS)
         const int count = colorAttachmentCount();
 
         static const GLenum drawBufs[4] = {
             GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1, GL_COLOR_ATTACHMENT2, GL_COLOR_ATTACHMENT3
         };
-        glDrawBuffers(count, drawBufs); LIBGUI_ASSERT_GL_OK();
-//        glReadBuffer(count > 0? GL_COLOR_ATTACHMENT0 : GL_NONE); LIBGUI_ASSERT_GL_OK();
+        glDrawBuffers(count, drawBufs);
+        LIBGUI_ASSERT_GL_OK();
+#endif
     }
 
     void glRelease() const
     {
         LIBGUI_ASSERT_GL_OK();
 
-        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, defaultFramebuffer); // both read and write FBOs
-//        glBindFramebuffer(GL_READ_FRAMEBUFFER, defaultFramebuffer); // both read and write FBOs
+        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, defaultFramebuffer);
         LIBGUI_ASSERT_GL_OK();
 
-        glDrawBuffer(GL_BACK);   LIBGUI_ASSERT_GL_OK();
-//        glReadBuffer(GL_BACK);   LIBGUI_ASSERT_GL_OK();
+#if defined (DE_HAVE_COLOR_ATTACHMENTS)
+        glDrawBuffer(GL_BACK);
+        LIBGUI_ASSERT_GL_OK();
+#endif        
     }
 
     void validate()
@@ -512,9 +525,7 @@ DE_PIMPL(GLFramebuffer)
         }
 
         DE_ASSERT(fbo != 0);
-
-        //glBindFramebuffer(GL_FRAMEBUFFER, fbo);
-
+
         glBind();
 
         GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
@@ -679,8 +690,8 @@ void GLFramebuffer::configure(const List<GLTexture *> &colorTextures,
         d->attachRenderbuffer(Impl::ColorBuffer0, GL_RGBA8, GL_COLOR_ATTACHMENT0);
     }
 
+    // The depth/stencil attachment(s).
 #if defined (DE_HAVE_DEPTH_STENCIL_ATTACHMENT)
-    // The depth attachment.
     if (depthStencilTex)
     {
         DE_ASSERT(depthStencilTex->isReady());
@@ -701,7 +712,7 @@ void GLFramebuffer::configure(const List<GLTexture *> &colorTextures,
     }
     else if (missingRenderBuffers & Depth)
     {
-        d->attachRenderBuffer(Impl::DepthBuffer, GL_DEPTH24_OES, GL_DEPTH_ATTACHMENT);
+        d->attachRenderbuffer(Impl::DepthBuffer, GL_DEPTH_COMPONENT24_OES, GL_DEPTH_ATTACHMENT);
     }
 
     if (stencilTex)
@@ -712,7 +723,7 @@ void GLFramebuffer::configure(const List<GLTexture *> &colorTextures,
     }
     else if (missingRenderBuffers & Stencil)
     {
-        d->attachRenderBuffer(Impl::StencilBuffer, GL_RED, GL_STENCIL_ATTACHMENT);
+        d->attachRenderbuffer(Impl::StencilBuffer, GL_STENCIL_INDEX, GL_STENCIL_ATTACHMENT);
     }
 #endif
 
@@ -830,11 +841,18 @@ void GLFramebuffer::clear(Flags attachments)
     glClearColor(d->clearColor.x, d->clearColor.y, d->clearColor.z, d->clearColor.w);
 
     // Only clear what we have.
-    Flags which = attachments & d->flags;
+    const Flags which = attachments & d->flags;
+
+#if defined (DE_HAVE_COLOR_ATTACHMENTS)
     glClear((which & (Color0 | Color1 | Color2 | Color3) ?
                                ClearBufferMask::GL_COLOR_BUFFER_BIT : ClearBufferMask::GL_NONE_BIT) |
             (which & Depth ?   ClearBufferMask::GL_DEPTH_BUFFER_BIT : ClearBufferMask::GL_NONE_BIT) |
             (which & Stencil ? ClearBufferMask::GL_STENCIL_BUFFER_BIT : ClearBufferMask::GL_NONE_BIT));
+#else
+    glClear((which & Color0  ? GL_COLOR_BUFFER_BIT : 0) |
+            (which & Depth   ? GL_DEPTH_BUFFER_BIT : 0) |
+            (which & Stencil ? GL_STENCIL_BUFFER_BIT: 0));
+#endif            
 
     // Restore previous state.
     if (attachments & FullClear)

diff --git a/doomsday/libs/gui/src/graphics/glinfo.cpp b/doomsday/libs/gui/src/graphics/glinfo.cpp
@@ -321,6 +321,7 @@ DE_PIMPL_NOREF(GLInfo) //, public QOpenGLFunctions_Doomsday
         ext.NV_framebuffer_multisample_coverage = query("GL_NV_framebuffer_multisample_coverage");
         ext.NV_texture_barrier                  = query("GL_NV_texture_barrier");
         ext.KHR_debug                           = query("GL_KHR_debug");
+        ext.OES_rgb8_rgba8                      = query("GL_OES_rgb8_rgba8");
 
 #if defined (DE_ENABLE_OPENGL_DEBUG_LOGGER)
         {
@@ -351,13 +352,13 @@ DE_PIMPL_NOREF(GLInfo) //, public QOpenGLFunctions_Doomsday
             glGetFloatv(GL_SMOOTH_LINE_WIDTH_GRANULARITY, &lim.smoothLineWidthGranularity);
             LIBGUI_ASSERT_GL_OK();
         }
-#endif
         LIBGUI_ASSERT_GL_OK();
 
         if (ext.EXT_texture_filter_anisotropic)
         {
             glGetIntegerv(gl33ext::GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &lim.maxTexFilterAniso);
         }
+#endif
 
         // Set a custom maximum size?
         if (CommandLine_CheckWith("-maxtex", 1))
@@ -368,23 +369,6 @@ DE_PIMPL_NOREF(GLInfo) //, public QOpenGLFunctions_Doomsday
             LOG_GL_NOTE("Using requested maximum texture size of %i x %i")
                 << lim.maxTexSize << lim.maxTexSize;
         }
-
-#if 0
-        // Check default OpenGL format attributes.
-        const QOpenGLContext *ctx = QOpenGLContext::currentContext();
-        QSurfaceFormat form = ctx->format();
-
-        LOGDEV_GL_MSG("Initial OpenGL format:");
-        LOGDEV_GL_MSG(" - version: %i.%i") << form.majorVersion() << form.minorVersion();
-        LOGDEV_GL_MSG(" - profile: %s") << (form.profile() == QSurfaceFormat::CompatibilityProfile? "Compatibility" : "Core");
-        LOGDEV_GL_MSG(" - color: R%i G%i B%i A%i bits") << form.redBufferSize() << form.greenBufferSize() << form.blueBufferSize() << form.alphaBufferSize();
-        LOGDEV_GL_MSG(" - depth: %i bits") << form.depthBufferSize();
-        LOGDEV_GL_MSG(" - stencil: %i bits") << form.stencilBufferSize();
-        LOGDEV_GL_MSG(" - samples: %i") << form.samples();
-        LOGDEV_GL_MSG(" - swap behavior: %i") << form.swapBehavior();
-
-        LIBGUI_ASSERT_GL_OK();
-#endif
     }
 };
 

diff --git a/doomsday/libs/gui/src/graphics/glshader.cpp b/doomsday/libs/gui/src/graphics/glshader.cpp
@@ -29,7 +29,6 @@ DE_PIMPL(GLShader)
 {
     GLuint name = 0;
     Type   type = Vertex;
-    //Block  compiledSource;
 
     Impl(Public *i) : Base(i)
     {}
@@ -44,9 +43,14 @@ DE_PIMPL(GLShader)
         LIBGUI_ASSERT_GL_CONTEXT_ACTIVE();
         if (!name)
         {
+#if defined (DE_OPENGL)
             name = glCreateShader(type == Vertex   ? GL_VERTEX_SHADER
-                                          : type == Geometry ? GL_GEOMETRY_SHADER
-                                                             : GL_FRAGMENT_SHADER);
+                                : type == Geometry ? GL_GEOMETRY_SHADER
+                                                   : GL_FRAGMENT_SHADER);
+#elif defined (DE_OPENGL_ES)
+            DE_ASSERT(type != Geometry);
+            name = glCreateShader(type == Vertex ? GL_VERTEX_SHADER : GL_FRAGMENT_SHADER);
+#endif
             LIBGUI_ASSERT_GL_OK();
             if (!name)
             {

diff --git a/doomsday/libs/gui/src/graphics/gltimer.cpp b/doomsday/libs/gui/src/graphics/gltimer.cpp
@@ -24,6 +24,8 @@
 
 namespace de {
 
+#if defined (DE_OPENGL)
+
 DE_PIMPL_NOREF(GLTimer)
 {
     static const int BUF_COUNT = 2;
@@ -142,4 +144,17 @@ TimeSpan GLTimer::elapsedTime(const Id &id) const
     return 0.0;
 }
 
+#endif // DE_OPENGL
+
+#if defined (DE_OPENGL_ES)
+
+// dummy implementation
+DE_PIMPL_NOREF(GLTimer) {};
+GLTimer::GLTimer() : d(new Impl) {}
+void GLTimer::beginTimer(const Id &) {}
+void GLTimer::endTimer(const Id &) {}
+TimeSpan GLTimer::elapsedTime(const Id &) const { return 0.0; }
+
+#endif
+
 } // namespace de