commit 60838d0d4b882993393a2c0c1b025a9cbbfd25c1
author Alexandros Frantzis <alexandros.frantzis@collabora.com> Tue Feb 02 15:55:12 2021
committer Alexandros Frantzis <alexandros.frantzis@collabora.com> Tue Feb 02 16:58:54 2021
tree 6e90fbe4233b1211be1c6b53711523c94376e127
parent 52089d1f6b60bb14298287936d3c6802d3b5d9b2

SceneRefract: Draw to correct FBO in off-screen mode

The "refract" scene incorrectly used FBO 0 in off-screen mode. This commit
updates the scene to properly handle a non-zero canvas FBO.

src/scene-refract.cpp

diff --git a/src/scene-refract.cpp b/src/scene-refract.cpp
index 4bc2fd8..0c726fc 100644
--- a/src/scene-refract.cpp
+++ b/src/scene-refract.cpp
@@ -177,7 +177,7 @@
 //
 
 bool
-DistanceRenderTarget::setup(unsigned int width, unsigned int height)
+DistanceRenderTarget::setup(unsigned int canvas_fbo, unsigned int width, unsigned int height)
 {
     static const string vtx_shader_filename(Options::data_path + "/shaders/depth.vert");
     static const string frg_shader_filename(Options::data_path + "/shaders/depth.frag");
@@ -193,6 +193,7 @@
     canvas_height_ = height;
     width_ = canvas_width_ * 2;
     height_ = canvas_height_ * 2;
+    canvas_fbo_ = canvas_fbo;
 
     // If the texture will be too large for the implemnetation, we need to
     // clamp the dimensions but maintain the aspect ratio.
@@ -236,7 +237,7 @@
         Log::error("DistanceRenderTarget::setup: glCheckFramebufferStatus failed (0x%x)\n", status);
         return false;
     }
-    glBindFramebuffer(GL_FRAMEBUFFER, 0);
+    glBindFramebuffer(GL_FRAMEBUFFER, canvas_fbo_);
 
     return true;
 }
@@ -273,7 +274,7 @@
 
 void DistanceRenderTarget::disable()
 {
-    glBindFramebuffer(GL_FRAMEBUFFER, 0);
+    glBindFramebuffer(GL_FRAMEBUFFER, canvas_fbo_);
     glViewport(0, 0, canvas_width_, canvas_height_);
     glCullFace(GL_BACK);
 }
@@ -383,7 +384,7 @@
                                       0.0, 0.0, 0.0,
                                       0.0, 1.0, 0.0);
 
-    if (!depthTarget_.setup(canvas_.width(), canvas_.height())) {
+    if (!depthTarget_.setup(canvas_.fbo(), canvas_.width(), canvas_.height())) {
         Log::error("Failed to set up the render target for the depth pass\n");
         return false;
     }

src/scene-refract.h

diff --git a/src/scene-refract.h b/src/scene-refract.h
index d8e65f0..3733a21 100644
--- a/src/scene-refract.h
+++ b/src/scene-refract.h
@@ -46,6 +46,7 @@
     unsigned int height_;
     unsigned int tex_[2];
     unsigned int fbo_;
+    unsigned int canvas_fbo_;
 public:
     DistanceRenderTarget() :
         canvas_width_(0),
@@ -57,7 +58,7 @@
         tex_[DEPTH] = tex_[COLOR] = 0;
     }
     ~DistanceRenderTarget() {}
-    bool setup(unsigned int width, unsigned int height);
+    bool setup(unsigned int canvas_fbo, unsigned int width, unsigned int height);
     void teardown();
     void enable(const LibMatrix::mat4& mvp);
     void disable();