diff options
Diffstat (limited to 'src/renderer/opengl/GlRenderer.cpp')
| -rw-r--r-- | src/renderer/opengl/GlRenderer.cpp | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/src/renderer/opengl/GlRenderer.cpp b/src/renderer/opengl/GlRenderer.cpp new file mode 100644 index 0000000..5d7c985 --- /dev/null +++ b/src/renderer/opengl/GlRenderer.cpp @@ -0,0 +1,220 @@ +#include <basic/defs.hpp> +#include <iterator> +#include <renderer/RenderGroup.hpp> +#include <renderer/opengl/GlRenderer.hpp> +#include <basic/math.hpp> +#include <renderer/Renderer.hpp> +#include <renderer/opengl/GlVertexBuffer.hpp> + +#include <SDL3/SDL.h> +#include <SDL3/SDL_video.h> +#include <GL/glew.h> +#include <GL/gl.h> +#include <assert.h> +#include <cstdio> + +void GLAPIENTRY +MessageCallback(GLenum source, + GLenum type, + GLuint id, + GLenum severity, + GLsizei length, + const GLchar* message, + const void* userParam) +{ + fprintf(stderr, "GL CALLBACK: %s, type = 0x%x, severity = 0x%x, message = %s\n", + type == GL_DEBUG_TYPE_ERROR ? "** GL ERROR **" : "", + type, + severity, + message + ); +} + +GlRenderer::~GlRenderer() { + SDL_GL_DestroyContext(m_Context); +} + +GlRenderer::GlRenderer(SDL_Window *window) + : m_Window(window), m_Context(nullptr) { +} + +bool GlRenderer::Init() { + SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3); + SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3); + SDL_GLContext sdl_gl_context = SDL_GL_CreateContext(m_Window); + if (!sdl_gl_context) { + return false; + } + + GLenum err = glewInit(); + if (GLEW_OK != err) + { + fprintf(stderr, "Error: %s\n", glewGetErrorString(err)); + SDL_GL_DestroyContext(sdl_gl_context); + return false; + } + +#if 0 + glEnable(GL_DEBUG_OUTPUT); + glDebugMessageCallback(MessageCallback, 0); +#endif + + GLuint vertex_array; + glGenVertexArrays(1, &vertex_array); + glBindVertexArray(vertex_array); + + + // init rectangle rendering + if (!m_RectangleShader.InitProgram()) { + return false; + } + m_RectangleVertexBuffer.Init(); + m_RectangleIndexBuffer.Init(); + + + // init text rendering + if (!m_TextShader.InitProgram()) { + return false; + } + m_TextVertexBuffer.Init(); + m_TextIndexBuffer.Init(); + + + m_Context = sdl_gl_context; + return true; +} + +void GlRenderer::Draw(RenderGroup& render_group) { + render_group.Sort(); + + float camera_width = render_group.m_CameraWidth; + float camera_height = render_group.m_CameraHeight; + + + glViewport(0, 0, render_group.m_ScreenWidth, render_group.m_ScreenHeight); + glClearColor(render_group.m_ClearColor.x, + render_group.m_ClearColor.y, + render_group.m_ClearColor.z, + 1.0f); + glClear(GL_COLOR_BUFFER_BIT); + + + // viewport space + float scale = render_group.GetScale(); + int32_t viewport_width = static_cast<int32_t>(camera_width * scale); + int32_t viewport_height = static_cast<int32_t>(camera_height * scale); + int32_t viewport_x0 = (render_group.m_ScreenWidth - viewport_width) / 2; + int32_t viewport_y0 = (render_group.m_ScreenHeight - viewport_height) / 2; + glViewport(viewport_x0, viewport_y0, viewport_width, viewport_height); + + + // draw batches + float last_z = -1; + for (auto [z, entity_index] : render_group.m_RSortEntries) { + REntity& render_entity = render_group.m_REntities[entity_index]; + switch (render_entity.type) { + case REntityType_Rectangle: { + // clip space (from camera space to [-1, 1] for pos and [0, 2] for dim) + V3F32 pos = render_entity.rect.pos; + V2F32 dim = render_entity.rect.dim; + pos.x = 2*(pos.x / camera_width) - 1; + pos.y = 2*(pos.y / camera_height) - 1; + dim.x = 2*(dim.x / camera_width); + dim.y = 2*(dim.y / camera_height); + + if (render_entity.rect.pos.z > last_z) { + DrawBatch(); + last_z = z; + } + + m_RectangleVertexBuffer.PushRectangle(pos, dim, render_entity.rect.color); + m_RectangleIndexBuffer.PushRectangle(); + } + + case REntityType_Bitmap: { + REntity_Bitmap& bitmap = render_entity.bitmap; + + // clip space (from camera space to [-1, 1] for pos and [0, 2] for dim) + V3F32 pos = render_entity.bitmap.pos; + pos.x = 2*(pos.x / camera_width) - 1; + pos.y = 2*(pos.y / camera_height) - 1; + +#if 0 + + // create setup texture + unsigned int texture_id; + glGenTextures(1, &texture_id); + glBindTexture(GL_TEXTURE_2D, texture_id); + glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, bitmap.width, bitmap.height, 0, GL_RGB, GL_UNSIGNED_BYTE, bitmap.data); + + glGenerateMipmap(GL_TEXTURE_2D); + + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); + + + // apply texture + glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float))); + glEnableVertexAttribArray(2); + + // delete texture + glDeleteTextures(1, &texture_id); + + + + // 1) set vertex buffer + // 2) set texture coordinates + pos.x = 2*(pos.x / camera_width) - 1; + pos.y = 2*(pos.y / camera_height) - 1; + dim.x = 2*(dim.x / camera_width); + dim.y = 2*(dim.y / camera_height); + if (render_entity.rect.pos.z > last_z) { + DrawBatch(); + last_z = z; + } +#endif + + + } break; + + InvalidDefaultCase; + } + } + + DrawBatch(); +} + +void GlRenderer::Present() { + SDL_GL_SwapWindow(m_Window); +} + +void GlRenderer::DrawBatch() { + int32_t rectangle_index_count = static_cast<int32_t>(m_RectangleIndexBuffer.GetCount()); + int32_t text_index_count = static_cast<int32_t>(m_TextIndexBuffer.GetCount()); + + if (rectangle_index_count) { + m_RectangleVertexBuffer.TransferData(); + m_RectangleIndexBuffer.TransferData(); + m_RectangleShader.UseProgram(); + + glDrawElements(GL_TRIANGLES, rectangle_index_count, GL_UNSIGNED_INT, 0); + + m_RectangleVertexBuffer.Reset(); + m_RectangleIndexBuffer.Reset(); + } + + if (text_index_count) { + m_TextVertexBuffer.TransferData(); + m_TextIndexBuffer.TransferData(); + m_TextShader.UseProgram(); + + glDrawElements(GL_TRIANGLES, text_index_count, GL_UNSIGNED_INT, 0); + + m_TextVertexBuffer.Reset(); + m_TextIndexBuffer.Reset(); + } +} + + |