raylib/examples/models/models_skybox.c
2023-02-14 20:00:51 +01:00

272 lines
13 KiB
C

/*******************************************************************************************
*
* raylib [models] example - Skybox loading and drawing
*
* Example originally created with raylib 1.8, last time updated with raylib 4.0
*
* Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
* BSD-like license that allows static linking with closed source software
*
* Copyright (c) 2017-2023 Ramon Santamaria (@raysan5)
*
********************************************************************************************/
#include "raylib.h"
#include "rlgl.h"
#include "raymath.h" // Required for: MatrixPerspective(), MatrixLookAt()
#if defined(PLATFORM_DESKTOP)
#define GLSL_VERSION 330
#else // PLATFORM_RPI, PLATFORM_ANDROID, PLATFORM_WEB
#define GLSL_VERSION 100
#endif
// Generate cubemap (6 faces) from equirectangular (panorama) texture
static TextureCubemap GenTextureCubemap(Shader shader, Texture2D panorama, int size, int format);
//------------------------------------------------------------------------------------
// Program main entry point
//------------------------------------------------------------------------------------
int main(void)
{
// Initialization
//--------------------------------------------------------------------------------------
const int screenWidth = 800;
const int screenHeight = 450;
InitWindow(screenWidth, screenHeight, "raylib [models] example - skybox loading and drawing");
// Define the camera to look into our 3d world
Camera camera = { 0 };
camera.position = (Vector3){ 1.0f, 1.0f, 1.0f }; // Camera position
camera.target = (Vector3){ 4.0f, 1.0f, 4.0f }; // Camera looking at point
camera.up = (Vector3){ 0.0f, 1.0f, 0.0f }; // Camera up vector (rotation towards target)
camera.fovy = 45.0f; // Camera field-of-view Y
camera.projection = CAMERA_PERSPECTIVE; // Camera projection type
// Load skybox model
Mesh cube = GenMeshCube(1.0f, 1.0f, 1.0f);
Model skybox = LoadModelFromMesh(cube);
bool useHDR = true;
// Load skybox shader and set required locations
// NOTE: Some locations are automatically set at shader loading
skybox.materials[0].shader = LoadShader(TextFormat("resources/shaders/glsl%i/skybox.vs", GLSL_VERSION),
TextFormat("resources/shaders/glsl%i/skybox.fs", GLSL_VERSION));
SetShaderValue(skybox.materials[0].shader, GetShaderLocation(skybox.materials[0].shader, "environmentMap"), (int[1]){ MATERIAL_MAP_CUBEMAP }, SHADER_UNIFORM_INT);
SetShaderValue(skybox.materials[0].shader, GetShaderLocation(skybox.materials[0].shader, "doGamma"), (int[1]) { useHDR ? 1 : 0 }, SHADER_UNIFORM_INT);
SetShaderValue(skybox.materials[0].shader, GetShaderLocation(skybox.materials[0].shader, "vflipped"), (int[1]){ useHDR ? 1 : 0 }, SHADER_UNIFORM_INT);
// Load cubemap shader and setup required shader locations
Shader shdrCubemap = LoadShader(TextFormat("resources/shaders/glsl%i/cubemap.vs", GLSL_VERSION),
TextFormat("resources/shaders/glsl%i/cubemap.fs", GLSL_VERSION));
SetShaderValue(shdrCubemap, GetShaderLocation(shdrCubemap, "equirectangularMap"), (int[1]){ 0 }, SHADER_UNIFORM_INT);
char skyboxFileName[256] = { 0 };
Texture2D panorama;
if (useHDR)
{
TextCopy(skyboxFileName, "resources/dresden_square_2k.hdr");
// Load HDR panorama (sphere) texture
panorama = LoadTexture(skyboxFileName);
// Generate cubemap (texture with 6 quads-cube-mapping) from panorama HDR texture
// NOTE 1: New texture is generated rendering to texture, shader calculates the sphere->cube coordinates mapping
// NOTE 2: It seems on some Android devices WebGL, fbo does not properly support a FLOAT-based attachment,
// despite texture can be successfully created.. so using PIXELFORMAT_UNCOMPRESSED_R8G8B8A8 instead of PIXELFORMAT_UNCOMPRESSED_R32G32B32A32
skybox.materials[0].maps[MATERIAL_MAP_CUBEMAP].texture = GenTextureCubemap(shdrCubemap, panorama, 1024, PIXELFORMAT_UNCOMPRESSED_R8G8B8A8);
//UnloadTexture(panorama); // Texture not required anymore, cubemap already generated
}
else
{
Image img = LoadImage("resources/skybox.png");
skybox.materials[0].maps[MATERIAL_MAP_CUBEMAP].texture = LoadTextureCubemap(img, CUBEMAP_LAYOUT_AUTO_DETECT); // CUBEMAP_LAYOUT_PANORAMA
UnloadImage(img);
}
DisableCursor(); // Limit cursor to relative movement inside the window
SetTargetFPS(60); // Set our game to run at 60 frames-per-second
//--------------------------------------------------------------------------------------
// Main game loop
while (!WindowShouldClose()) // Detect window close button or ESC key
{
// Update
//----------------------------------------------------------------------------------
UpdateCamera(&camera, CAMERA_FIRST_PERSON);
// Load new cubemap texture on drag&drop
if (IsFileDropped())
{
FilePathList droppedFiles = LoadDroppedFiles();
if (droppedFiles.count == 1) // Only support one file dropped
{
if (IsFileExtension(droppedFiles.paths[0], ".png;.jpg;.hdr;.bmp;.tga"))
{
// Unload current cubemap texture and load new one
UnloadTexture(skybox.materials[0].maps[MATERIAL_MAP_CUBEMAP].texture);
if (useHDR)
{
Texture2D panorama = LoadTexture(droppedFiles.paths[0]);
// Generate cubemap from panorama texture
skybox.materials[0].maps[MATERIAL_MAP_CUBEMAP].texture = GenTextureCubemap(shdrCubemap, panorama, 1024, PIXELFORMAT_UNCOMPRESSED_R8G8B8A8);
UnloadTexture(panorama);
}
else
{
Image img = LoadImage(droppedFiles.paths[0]);
skybox.materials[0].maps[MATERIAL_MAP_CUBEMAP].texture = LoadTextureCubemap(img, CUBEMAP_LAYOUT_AUTO_DETECT);
UnloadImage(img);
}
TextCopy(skyboxFileName, droppedFiles.paths[0]);
}
}
UnloadDroppedFiles(droppedFiles); // Unload filepaths from memory
}
//----------------------------------------------------------------------------------
// Draw
//----------------------------------------------------------------------------------
BeginDrawing();
ClearBackground(RAYWHITE);
BeginMode3D(camera);
// We are inside the cube, we need to disable backface culling!
rlDisableBackfaceCulling();
rlDisableDepthMask();
DrawModel(skybox, (Vector3){0, 0, 0}, 1.0f, WHITE);
rlEnableBackfaceCulling();
rlEnableDepthMask();
DrawGrid(10, 1.0f);
EndMode3D();
//DrawTextureEx(panorama, (Vector2){ 0, 0 }, 0.0f, 0.5f, WHITE);
if (useHDR) DrawText(TextFormat("Panorama image from hdrihaven.com: %s", GetFileName(skyboxFileName)), 10, GetScreenHeight() - 20, 10, BLACK);
else DrawText(TextFormat(": %s", GetFileName(skyboxFileName)), 10, GetScreenHeight() - 20, 10, BLACK);
DrawFPS(10, 10);
EndDrawing();
//----------------------------------------------------------------------------------
}
// De-Initialization
//--------------------------------------------------------------------------------------
UnloadShader(skybox.materials[0].shader);
UnloadTexture(skybox.materials[0].maps[MATERIAL_MAP_CUBEMAP].texture);
UnloadModel(skybox); // Unload skybox model
CloseWindow(); // Close window and OpenGL context
//--------------------------------------------------------------------------------------
return 0;
}
// Generate cubemap texture from HDR texture
static TextureCubemap GenTextureCubemap(Shader shader, Texture2D panorama, int size, int format)
{
TextureCubemap cubemap = { 0 };
rlDisableBackfaceCulling(); // Disable backface culling to render inside the cube
// STEP 1: Setup framebuffer
//------------------------------------------------------------------------------------------
unsigned int rbo = rlLoadTextureDepth(size, size, true);
cubemap.id = rlLoadTextureCubemap(0, size, format);
unsigned int fbo = rlLoadFramebuffer(size, size);
rlFramebufferAttach(fbo, rbo, RL_ATTACHMENT_DEPTH, RL_ATTACHMENT_RENDERBUFFER, 0);
rlFramebufferAttach(fbo, cubemap.id, RL_ATTACHMENT_COLOR_CHANNEL0, RL_ATTACHMENT_CUBEMAP_POSITIVE_X, 0);
// Check if framebuffer is complete with attachments (valid)
if (rlFramebufferComplete(fbo)) TraceLog(LOG_INFO, "FBO: [ID %i] Framebuffer object created successfully", fbo);
//------------------------------------------------------------------------------------------
// STEP 2: Draw to framebuffer
//------------------------------------------------------------------------------------------
// NOTE: Shader is used to convert HDR equirectangular environment map to cubemap equivalent (6 faces)
rlEnableShader(shader.id);
// Define projection matrix and send it to shader
Matrix matFboProjection = MatrixPerspective(90.0*DEG2RAD, 1.0, RL_CULL_DISTANCE_NEAR, RL_CULL_DISTANCE_FAR);
rlSetUniformMatrix(shader.locs[SHADER_LOC_MATRIX_PROJECTION], matFboProjection);
// Define view matrix for every side of the cubemap
Matrix fboViews[6] = {
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 1.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ -1.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 1.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, 1.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, -1.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, 1.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, -1.0f }, (Vector3){ 0.0f, -1.0f, 0.0f })
};
rlViewport(0, 0, size, size); // Set viewport to current fbo dimensions
// Activate and enable texture for drawing to cubemap faces
rlActiveTextureSlot(0);
rlEnableTexture(panorama.id);
for (int i = 0; i < 6; i++)
{
// Set the view matrix for the current cube face
rlSetUniformMatrix(shader.locs[SHADER_LOC_MATRIX_VIEW], fboViews[i]);
// Select the current cubemap face attachment for the fbo
// WARNING: This function by default enables->attach->disables fbo!!!
rlFramebufferAttach(fbo, cubemap.id, RL_ATTACHMENT_COLOR_CHANNEL0, RL_ATTACHMENT_CUBEMAP_POSITIVE_X + i, 0);
rlEnableFramebuffer(fbo);
// Load and draw a cube, it uses the current enabled texture
rlClearScreenBuffers();
rlLoadDrawCube();
// ALTERNATIVE: Try to use internal batch system to draw the cube instead of rlLoadDrawCube
// for some reason this method does not work, maybe due to cube triangles definition? normals pointing out?
// TODO: Investigate this issue...
//rlSetTexture(panorama.id); // WARNING: It must be called after enabling current framebuffer if using internal batch system!
//rlClearScreenBuffers();
//DrawCubeV(Vector3Zero(), Vector3One(), WHITE);
//rlDrawRenderBatchActive();
}
//------------------------------------------------------------------------------------------
// STEP 3: Unload framebuffer and reset state
//------------------------------------------------------------------------------------------
rlDisableShader(); // Unbind shader
rlDisableTexture(); // Unbind texture
rlDisableFramebuffer(); // Unbind framebuffer
rlUnloadFramebuffer(fbo); // Unload framebuffer (and automatically attached depth texture/renderbuffer)
// Reset viewport dimensions to default
rlViewport(0, 0, rlGetFramebufferWidth(), rlGetFramebufferHeight());
rlEnableBackfaceCulling();
//------------------------------------------------------------------------------------------
cubemap.width = size;
cubemap.height = size;
cubemap.mipmaps = 1;
cubemap.format = format;
return cubemap;
}