Merge pull request #190 from bjornbytes/android-canvas

Android Canvas

src/modules/graphics/canvas.c

@@ -31,7 +31,9 @@ void lovrCanvasSetAttachments(Canvas* canvas, Attachment* attachments, uint32_t
     lovrAssert(level < mipmaps, "Invalid attachment mipmap level (Texture has %d, got %d)", mipmaps, level + 1);
     lovrAssert(!hasDepthBuffer || width == canvas->width, "Texture width of %d does not match Canvas width (%d)", width, canvas->width);
     lovrAssert(!hasDepthBuffer || height == canvas->height, "Texture height of %d does not match Canvas height (%d)", height, canvas->height);
+#ifndef __ANDROID__ // On multiview canvases, the multisample settings can be different
     lovrAssert(texture->msaa == canvas->flags.msaa, "Texture MSAA does not match Canvas MSAA");
+#endif
     lovrRetain(texture);
   }
 

src/modules/graphics/opengl.c

@@ -666,11 +666,6 @@ static void lovrGpuBindCanvas(Canvas* canvas, bool willDraw) {
   }
 #endif
 
-  // Use the read framebuffer as a binding point to bind resolve textures
-  if (canvas->flags.msaa) {
-    glBindFramebuffer(GL_READ_FRAMEBUFFER, canvas->resolveBuffer);
-  }
-
   GLenum buffers[MAX_CANVAS_ATTACHMENTS] = { GL_NONE };
   for (uint32_t i = 0; i < canvas->attachmentCount; i++) {
     GLenum drawBuffer = buffers[i] = GL_COLOR_ATTACHMENT0 + i;
@@ -683,11 +678,12 @@ static void lovrGpuBindCanvas(Canvas* canvas, bool willDraw) {
 #ifdef LOVR_WEBGL
       lovrThrow("Unreachable");
 #else
-      glFramebufferTextureMultisampleMultiviewOVR(GL_READ_FRAMEBUFFER, drawBuffer, texture->id, level, canvas->flags.msaa, slice, 2);
+      glFramebufferTextureMultisampleMultiviewOVR(GL_FRAMEBUFFER, drawBuffer, texture->id, level, canvas->flags.msaa, slice, 2);
 #endif
     } else {
       if (canvas->flags.msaa) {
         glFramebufferRenderbuffer(GL_FRAMEBUFFER, drawBuffer, GL_RENDERBUFFER, texture->msaaId);
+        glBindFramebuffer(GL_READ_FRAMEBUFFER, canvas->resolveBuffer);
       }
 
       switch (texture->type) {
@@ -1484,7 +1480,7 @@ void lovrTextureAllocate(Texture* texture, uint32_t width, uint32_t height, uint
 
   GLenum glFormat = convertTextureFormat(format);
   GLenum internalFormat = convertTextureFormatInternal(format, texture->srgb);
-#ifndef LOVR_WEBGL
+#ifdef LOVR_GL
   if (GLAD_GL_ARB_texture_storage) {
 #endif
   if (texture->type == TEXTURE_ARRAY) {
@@ -1492,7 +1488,7 @@ void lovrTextureAllocate(Texture* texture, uint32_t width, uint32_t height, uint
   } else {
     glTexStorage2D(texture->target, texture->mipmapCount, internalFormat, width, height);
   }
-#ifndef LOVR_WEBGL
+#ifdef LOVR_GL
   } else {
     for (uint32_t i = 0; i < texture->mipmapCount; i++) {
       switch (texture->type) {
@@ -1672,7 +1668,8 @@ Canvas* lovrCanvasInit(Canvas* canvas, uint32_t width, uint32_t height, CanvasFl
     lovrAssert(isTextureFormatDepth(flags.depth.format), "Canvas depth buffer can't use a color TextureFormat");
     GLenum attachment = flags.depth.format == FORMAT_D24S8 ? GL_DEPTH_STENCIL_ATTACHMENT : GL_DEPTH_ATTACHMENT;
     if (flags.stereo && state.singlepass == MULTIVIEW) {
-      canvas->depth.texture = lovrTextureCreate(TEXTURE_ARRAY, NULL, 0, false, flags.mipmaps, flags.msaa);
+      // Zero MSAA is intentional here, we attach it to the Canvas using legacy MSAA technique
+      canvas->depth.texture = lovrTextureCreate(TEXTURE_ARRAY, NULL, 0, false, flags.mipmaps, 0);
       lovrTextureAllocate(canvas->depth.texture, width, height, 2, flags.depth.format);
 #ifdef LOVR_WEBGL
       lovrThrow("Unreachable");
@@ -1692,7 +1689,7 @@ Canvas* lovrCanvasInit(Canvas* canvas, uint32_t width, uint32_t height, CanvasFl
     }
   }
 
-  if (flags.msaa) {
+  if (flags.msaa && (!flags.stereo || state.singlepass != MULTIVIEW)) {
     glGenFramebuffers(1, &canvas->resolveBuffer);
   }
 
@@ -1732,7 +1729,9 @@ void lovrCanvasResolve(Canvas* canvas) {
 
   lovrGraphicsFlushCanvas(canvas);
 
-  if (canvas->flags.msaa) {
+  // We don't need to resolve a multiview Canvas because it uses the legacy multisampling method in
+  // which the driver does an implicit multisample resolve whenever the canvas textures are read.
+  if (canvas->flags.msaa && (!canvas->flags.stereo || state.singlepass != MULTIVIEW)) {
     uint32_t w = canvas->width;
     uint32_t h = canvas->height;
     glBindFramebuffer(GL_READ_FRAMEBUFFER, canvas->framebuffer);

src/modules/headset/oculus_mobile.c

@@ -3,6 +3,7 @@
 #include "graphics/graphics.h"
 #include "graphics/canvas.h"
 #include "core/os.h"
+#include "core/ref.h"
 #include "lib/glad/glad.h"
 #include <android/log.h>
 #include <assert.h>
@@ -20,6 +21,9 @@ static struct {
   BridgeLovrDevice deviceType;
   BridgeLovrVibrateFunction* vibrateFunction;
   BridgeLovrUpdateData updateData;
+  uint32_t textureHandles[4];
+  uint32_t textureCount;
+  Canvas* canvases[4];
 } bridgeLovrMobileData;
 
 // Headset
@@ -438,6 +442,8 @@ void bridgeLovrInit(BridgeLovrInitData *initData) {
   bridgeLovrMobileData.updateData.displayTime = initData->zeroDisplayTime;
   bridgeLovrMobileData.deviceType = initData->deviceType;
   bridgeLovrMobileData.vibrateFunction = initData->vibrateFunction;
+  memcpy(bridgeLovrMobileData.textureHandles, initData->textureHandles, initData->textureCount * sizeof(uint32_t));
+  bridgeLovrMobileData.textureCount = initData->textureCount;
 
   free(apkPath);
   size_t length = strlen(initData->apkPath);
@@ -491,15 +497,30 @@ void bridgeLovrDraw(BridgeLovrDrawData *drawData) {
 
   lovrGpuDirtyTexture(); // Clear texture state since LÖVR doesn't completely own the GL context
 
-  // Initialize a temporary Canvas from the framebuffer handle created by lovr-oculus-mobile
-  Canvas canvas = { 0 };
-  CanvasFlags flags = { .stereo = true };
-  uint32_t width = bridgeLovrMobileData.displayDimensions.width;
-  uint32_t height = bridgeLovrMobileData.displayDimensions.height;
-  lovrCanvasInitFromHandle(&canvas, width, height, flags, drawData->framebuffer, 0, 0, 1, true);
+  // Lazily create Canvas objects on the first frame
+  if (!bridgeLovrMobileData.canvases[0]) {
+    for (uint32_t i = 0; i < bridgeLovrMobileData.textureCount; i++) {
+      uint32_t width = bridgeLovrMobileData.displayDimensions.width;
+      uint32_t height = bridgeLovrMobileData.displayDimensions.height;
+
+      bridgeLovrMobileData.canvases[i] = lovrCanvasCreate(width, height, (CanvasFlags) {
+        .depth.enabled = true,
+        .depth.readable = false,
+        .depth.format = FORMAT_D24S8,
+        .msaa = 4,
+        .stereo = true,
+        .mipmaps = false
+      });
+
+      uint32_t handle = bridgeLovrMobileData.textureHandles[i];
+      Texture* texture = lovrTextureCreateFromHandle(handle, TEXTURE_ARRAY, 2);
+      lovrCanvasSetAttachments(bridgeLovrMobileData.canvases[i], &(Attachment) { .texture = texture }, 1);
+      lovrRelease(Texture, texture);
+    }
+  }
 
   // Set up a camera using the view and projection matrices from lovr-oculus-mobile
-  Camera camera = { .canvas = &canvas };
+  Camera camera = { .canvas = bridgeLovrMobileData.canvases[drawData->textureIndex] };
   mat4_init(camera.viewMatrix[0], bridgeLovrMobileData.updateData.eyeViewMatrix[0]);
   mat4_init(camera.viewMatrix[1], bridgeLovrMobileData.updateData.eyeViewMatrix[1]);
   mat4_init(camera.projection[0], bridgeLovrMobileData.updateData.projectionMatrix[0]);
@@ -512,8 +533,8 @@ void bridgeLovrDraw(BridgeLovrDrawData *drawData) {
   lovrSetErrorCallback(luax_vthrow, L);
   state.renderCallback(state.renderUserdata);
 
+  lovrGraphicsDiscard(false, true, true);
   lovrGraphicsSetCamera(NULL, false);
-  lovrCanvasDestroy(&canvas);
 }
 
 // Android activity has been stopped or resumed
@@ -536,4 +557,8 @@ void bridgeLovrClose() {
   pauseState = PAUSESTATE_NONE;
   lua_close(L);
   free(lovrOculusMobileWritablePath);
+  for (uint32_t i = 0; i < bridgeLovrMobileData.textureCount; i++) {
+    lovrRelease(Canvas, bridgeLovrMobileData.canvases[i]);
+  }
+  memset(&bridgeLovrMobileData, 0, sizeof(bridgeLovrMobileData));
 }

src/modules/headset/oculus_mobile_bridge.h

@@ -126,6 +126,8 @@ typedef struct {
   double zeroDisplayTime;
   BridgeLovrDevice deviceType;
   BridgeLovrVibrateFunction* vibrateFunction; // Returns true on success
+  unsigned int textureHandles[4];
+  unsigned int textureCount;
 } BridgeLovrInitData;
 
 LOVR_EXPORT void bridgeLovrInit(BridgeLovrInitData *initData);
@@ -135,6 +137,7 @@ LOVR_EXPORT void bridgeLovrUpdate(BridgeLovrUpdateData *updateData);
 typedef struct {
   int eye;
   int framebuffer;
+  unsigned int textureIndex;
 } BridgeLovrDrawData;
 
 LOVR_EXPORT void bridgeLovrDraw(BridgeLovrDrawData *drawData);