| // Copyright 2017 Google Inc. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #ifndef COBALT_RENDERER_RASTERIZER_EGL_DRAW_OBJECT_H_ |
| #define COBALT_RENDERER_RASTERIZER_EGL_DRAW_OBJECT_H_ |
| |
| #include "cobalt/base/type_id.h" |
| #include "cobalt/math/matrix3_f.h" |
| #include "cobalt/math/rect.h" |
| #include "cobalt/render_tree/color_rgba.h" |
| #include "cobalt/renderer/rasterizer/egl/graphics_state.h" |
| #include "cobalt/renderer/rasterizer/egl/shader_program_manager.h" |
| |
| namespace cobalt { |
| namespace renderer { |
| namespace rasterizer { |
| namespace egl { |
| |
| // Base type to rasterize various objects via GL commands. |
| class DrawObject { |
| public: |
| // Structure containing the common attributes for all DrawObjects. |
| struct BaseState { |
| BaseState(); |
| BaseState(const BaseState& other); |
| |
| math::Matrix3F transform; |
| math::Rect scissor; |
| float depth; |
| float opacity; |
| }; |
| |
| virtual ~DrawObject() {} |
| |
| // This stage is used to render to offscreen targets. It specifically runs |
| // before vertex data is updated for onscreen rendering in order to allow |
| // this stage to modify that data. For example, this stage may rasterize to |
| // an offscreen atlas, so the location within the atlas might impact the |
| // texture coordinates used for the onscreen rasterize stage. |
| // |
| // If this stage needs to use vertex data of its own, then a new stage, |
| // ExecuteOffscreenUpdateVertexBuffer, should be created. This stage should |
| // be handled similarly to the current ExecuteOnscreenUpdateVertexBuffer. |
| virtual void ExecuteOffscreenRasterize(GraphicsState* graphics_state, |
| ShaderProgramManager* program_manager) {} |
| |
| // This stage is used to update the vertex buffer for the onscreen rasterize |
| // stage. Vertex data is handled by the GraphicsState to minimize the number |
| // of vertex buffers needed. Once this stage is executed, the rasterizer will |
| // then notify the GraphicsState to send all vertex data from all draw |
| // objects to the GPU. |
| virtual void ExecuteOnscreenUpdateVertexBuffer(GraphicsState* graphics_state, |
| ShaderProgramManager* program_manager) = 0; |
| |
| // This stage is used to render to the main render target. Although it can be |
| // used to rasterize to any number of render targets, it is best to use a |
| // different stage for offscreen rendering in order to minimize the cost of |
| // switching render targets. |
| virtual void ExecuteOnscreenRasterize(GraphicsState* graphics_state, |
| ShaderProgramManager* program_manager) = 0; |
| |
| protected: |
| explicit DrawObject(const BaseState& base_state); |
| |
| // Return a uint32_t suitable to be transferred as 4 unsigned bytes |
| // representing color to a GL shader. |
| static uint32_t GetGLRGBA(float r, float g, float b, float a); |
| static uint32_t GetGLRGBA(const render_tree::ColorRGBA& color) { |
| return GetGLRGBA(color.r(), color.g(), color.b(), color.a()); |
| } |
| |
| BaseState base_state_; |
| }; |
| |
| } // namespace egl |
| } // namespace rasterizer |
| } // namespace renderer |
| } // namespace cobalt |
| |
| #endif // COBALT_RENDERER_RASTERIZER_EGL_DRAW_OBJECT_H_ |