diff options
| -rw-r--r-- | src/mesa/tnl/t_context.h | 44 |
1 files changed, 30 insertions, 14 deletions
diff --git a/src/mesa/tnl/t_context.h b/src/mesa/tnl/t_context.h index 5247682e69..943082d99b 100644 --- a/src/mesa/tnl/t_context.h +++ b/src/mesa/tnl/t_context.h @@ -37,24 +37,39 @@ * necessary transformations (rotations, clipping, vertex shader etc.) * and passes then the output to the rasterizer. * - * The gl_pipeline contains an array of stages. The stages are - * black-boxes, which are described by gl_pipeline_stage. - * The function _tnl_run_pipeline (in file t_pipeline.c) applies all - * the stages to the vertex buffer. - * Note that the last stage in the pipeline is the rasterizer. + * The gl_pipeline contains the array of all stages, which should be + * applied. Each stage is a black-box, which is described by an + * gl_pipeline_stage. The function ::_tnl_run_pipeline applies all the + * stages to the vertex_buffer TNLcontext::vb, where the vertex data + * is stored. The last stage in the pipeline is the rasterizer. * - * _tnl_run_pipeline is called either, when the vertex buffer is full or - * when a state change flushes the pipeline. - * Note that _tnl_run_pipeline is not called directly but via - * tnl_device_driver::RunPipeline, which is stored in TNLcontext::Driver. + * The initial vertex_buffer data may either come from an ::immediate + * structure or client vertex_arrays or display lists: * - * The 'immediate' structure records all the GL commands issued between - * glBegin and glEnd. The 'vertex_buffer' structure stores the vertex - * data as its passed through the pipeline stages. The initial vertex_buffer - * data may either come from the 'immediate' structure or client vertex - * arrays or display lists. + * + * - The ::immediate structure records all the GL commands issued between + * glBegin and glEnd. \n + * The structure accumulates data, until it is either full or it is + * flushed (usually by a state change). Before starting then the pipeline, + * the collected vertex data in ::immediate has to be pushed into + * TNLcontext::vb. + * This happens in ::_tnl_vb_bind_immediate. The pipeline is then run by + * calling tnl_device_driver::RunPipeline = ::_tnl_run_pipeline, which + * is stored in TNLcontext::Driver. \n + * An ::immediate does (for performance reasons) usually not finish with a + * glEnd, and hence it also does not need to start with a glBegin. + * This means that the last vertices of one ::immediate may need to be + * saved for the next one. + * + * + * - NOT SURE ABOUT THIS: The vertex_arrays structure is used to handle + * glDrawArrays etc. \n + * Here, the data of the vertex_arrays is copied by ::_tnl_vb_bind_arrays + * into TNLcontext::vb, so that the pipeline can be started. */ +/* What is ELT? */ + #ifndef _T_CONTEXT_H #define _T_CONTEXT_H @@ -168,6 +183,7 @@ /** + * \struct immediate * Stores everything that can take place between a glBegin and glEnd. * Adjacent glBegin/glEnd pairs are stored back-to-back when there's no * state changes between them. |