When doing glReadPixels(), make sure we read from the right FBO.

[mlt] / src / modules / opengl / filter_glsl_manager.cpp

diff --git a/src/modules/opengl/filter_glsl_manager.cpp b/src/modules/opengl/filter_glsl_manager.cpp
index a09f8099cb4be13aa7600e3af9f777dded4af253..468e3b0422ef409facf577eadf5357a0f4e000c7 100644 (file)
--- a/src/modules/opengl/filter_glsl_manager.cpp
+++ b/src/modules/opengl/filter_glsl_manager.cpp
@@ -22,6 +22,7 @@
 #include <string>
 #include "glsl_manager.h"
 #include <movit/init.h>
+#include <movit/util.h>
 #include <movit/effect_chain.h>
 #include "mlt_movit_input.h"
 #include "mlt_flip_effect.h"
@@ -340,7 +341,7 @@ Effect* GlslManager::add_effect( mlt_filter filter, mlt_frame frame, Effect* eff
        return effect;
 }
 
-void GlslManager::render( mlt_service service, void* chain, GLuint fbo, int width, int height )
+void GlslManager::render_fbo( mlt_service service, void* chain, GLuint fbo, int width, int height )
 {
        EffectChain* effect_chain = (EffectChain*) chain;
        mlt_properties properties = MLT_SERVICE_PROPERTIES( service );
@@ -352,6 +353,116 @@ void GlslManager::render( mlt_service service, void* chain, GLuint fbo, int widt
        effect_chain->render_to_fbo( fbo, width, height );
 }
 
+int GlslManager::render_frame_texture(mlt_service service, mlt_frame frame, int width, int height, uint8_t **image)
+{
+       EffectChain* chain = get_chain( service );
+       if (!chain) return 1;
+       glsl_fbo fbo = get_fbo( width, height );
+       if (!fbo) return 1;
+       glsl_texture texture = get_texture( width, height, GL_RGBA );
+       if (!texture) {
+               release_fbo( fbo );
+               return 1;
+       }
+
+       glBindFramebuffer( GL_FRAMEBUFFER, fbo->fbo );
+       check_error();
+       glFramebufferTexture2D( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture->texture, 0 );
+       check_error();
+       glBindFramebuffer( GL_FRAMEBUFFER, 0 );
+       check_error();
+
+       render_fbo( service, chain, fbo->fbo, width, height );
+
+       glFinish();
+       check_error();
+       glBindFramebuffer( GL_FRAMEBUFFER, 0 );
+       check_error();
+       release_fbo( fbo );
+
+       *image = (uint8_t*) &texture->texture;
+       mlt_frame_set_image( frame, *image, 0, NULL );
+       mlt_properties_set_data( MLT_FRAME_PROPERTIES(frame), "movit.convert.texture", texture, 0,
+               (mlt_destructor) GlslManager::release_texture, NULL );
+
+       return 0;
+}
+
+int GlslManager::render_frame_rgba(mlt_service service, mlt_frame frame, int width, int height, uint8_t **image)
+{
+       EffectChain* chain = get_chain( service );
+       if (!chain) return 1;
+       glsl_fbo fbo = get_fbo( width, height );
+       if (!fbo) return 1;
+       glsl_texture texture = get_texture( width, height, GL_RGBA );
+       if (!texture) {
+               release_fbo( fbo );
+               return 1;
+       }
+
+       // Use a PBO to hold the data we read back with glReadPixels().
+       // (Intel/DRI goes into a slow path if we don't read to PBO.)
+       int img_size = width * height * 4;
+       glsl_pbo pbo = get_pbo( img_size );
+       if (!pbo) {
+               release_fbo( fbo );
+               release_texture(texture);
+               return 1;
+       }
+
+       // Set the FBO
+       check_error();
+       glBindFramebuffer( GL_FRAMEBUFFER, fbo->fbo );
+       check_error();
+       glFramebufferTexture2D( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture->texture, 0 );
+       check_error();
+       glBindFramebuffer( GL_FRAMEBUFFER, 0 );
+       check_error();
+
+       render_fbo( service, chain, fbo->fbo, width, height );
+
+       // Read FBO into PBO
+       glBindFramebuffer( GL_FRAMEBUFFER, fbo->fbo );
+       check_error();
+       glBindBuffer( GL_PIXEL_PACK_BUFFER_ARB, pbo->pbo );
+       check_error();
+       glBufferData( GL_PIXEL_PACK_BUFFER_ARB, img_size, NULL, GL_STREAM_READ );
+       check_error();
+       glReadPixels( 0, 0, width, height, GL_BGRA, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0) );
+       check_error();
+
+       // Copy from PBO
+       uint8_t* buf = (uint8_t*) glMapBuffer( GL_PIXEL_PACK_BUFFER_ARB, GL_READ_ONLY );
+       check_error();
+       *image = (uint8_t*) mlt_pool_alloc( img_size );
+       mlt_frame_set_image( frame, *image, img_size, mlt_pool_release );
+       memcpy( *image, buf, img_size );
+
+       // Convert BGRA to RGBA
+       register uint8_t *p = *image;
+       register int n = width * height + 1;
+       while ( --n ) {
+               uint8_t b = p[0];
+               *p = p[2]; p += 2;
+               *p = b; p += 2;
+       }
+
+       // Release PBO and FBO
+       glUnmapBuffer( GL_PIXEL_PACK_BUFFER_ARB );
+       check_error();
+       glBindBuffer( GL_PIXEL_PACK_BUFFER_ARB, 0 );
+       check_error();
+       glBindFramebuffer( GL_FRAMEBUFFER, 0 );
+       check_error();
+       glBindTexture( GL_TEXTURE_2D, 0 );
+       check_error();
+       mlt_properties_set_data( MLT_FRAME_PROPERTIES(frame), "movit.convert.texture", texture, 0,
+               (mlt_destructor) GlslManager::release_texture, NULL);
+       release_fbo( fbo );
+
+       return 0;
+}
+
 void GlslManager::lock_service( mlt_frame frame )
 {
        Mlt::Producer producer( mlt_producer_cut_parent( mlt_frame_get_original_producer( frame ) ) );